Update python binding to pyo3 0.29.0

Builds on #57. Swap Value::Object's payload from Rc<BTreeMap<Value, Value>>
to Rc<Object> and migrate all call sites to the Object API.

as_object / as_object_mut keep their names but return &Object / &mut Object.
The mutable accessor handles Rc::make_mut internally, so callers no longer
do it themselves. Object grows into_value() and From<Object> for Value.
Value's serializer now delegates to Object::serialize, dropping a duplicate
non-string-key stringification path.

RVM IterationState::Object is rewritten around ObjectCursor: O(log n)
steps over a shared Rc<Object>, no eager pair snapshot. Snapshot
independence is preserved by Rc copy-on-write; setup_next_iteration
advances the cursor inline and advance() becomes a no-op for this variant.
A new iteration_state_object_is_snapshot_independent_of_source test
covers CoW against a mutated alias.

Value::Set still wraps Rc<BTreeSet<Value>>; the matching Set abstraction
and its swap ship in follow-up PRs.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Cargo.lock

@@ -119,9 +119,9 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bit-set"
@@ -162,9 +162,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -402,9 +402,9 @@ checksum = "460fbee9c2c2f33933d720630a6a0bac33ba7053db5344fac858d4b8952d77d5"
 
 [[package]]
 name = "dashmap"
-version = "6.1.0"
+version = "6.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5041cc499144891f3790297212f32a74fb938e5136a14943f338ef9e0ae276cf"
+checksum = "e6361d5c062261c78a176addb82d4c821ae42bed6089de0e12603cd25de2059c"
 dependencies = [
  "cfg-if",
  "crossbeam-utils",
@@ -422,9 +422,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2 1.0.106",
  "quote 1.0.45",
@@ -433,9 +433,9 @@ dependencies = [
 
 [[package]]
 name = "either"
-version = "1.15.0"
+version = "1.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+checksum = "91622ff5e7162018101f2fea40d6ebf4a78bbe5a49736a2020649edf9693679e"
 
 [[package]]
 name = "email_address"
@@ -869,9 +869,9 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -944,9 +944,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -956,9 +956,9 @@ checksum = "8a860605968fce16869fd239cf4237a82f3ac470723415db603b0e8b6c8d4fb9"
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -1431,7 +1431,7 @@ dependencies = [
  "serde",
  "serde_json",
  "serde_yaml",
- "spin 0.10.0",
+ "spin 0.12.0",
  "test-generator",
  "thiserror",
  "url",
@@ -1518,9 +1518,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1580,9 +1580,9 @@ checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1693,9 +1693,9 @@ dependencies = [
 
 [[package]]
 name = "toml_edit"
-version = "0.25.11+spec-1.1.0"
+version = "0.25.12+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b59c4d22ed448339746c59b905d24568fcbb3ab65a500494f7b8c3e97739f2b"
+checksum = "d2153edc6955a6c354fad8f5efd38b6a8769bdccf9fe50f8e1329f81b0baa5d7"
 dependencies = [
  "indexmap",
  "toml_datetime",
@@ -1841,9 +1841,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1854,9 +1854,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote 1.0.45",
  "wasm-bindgen-macro-support",
@@ -1864,9 +1864,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2 1.0.106",
@@ -1877,9 +1877,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
@@ -1920,9 +1920,9 @@ dependencies = [
 
 [[package]]
 name = "web-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4b572dff8bcf38bad0fa19729c89bb5748b2b9b1d8be70cf90df697e3a8f32aa"
+checksum = "6d621441cfc37b84979402712047321980c178f299193a3589d05b99e8763436"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -2029,9 +2029,9 @@ dependencies = [
 
 [[package]]
 name = "winnow"
-version = "1.0.2"
+version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2ee1708bef14716a11bae175f579062d4554d95be2c6829f518df847b7b3fdd0"
+checksum = "0592e1c9d151f854e6fd382574c3a0855250e1d9b2f99d9281c6e6391af352f1"
 dependencies = [
  "memchr",
 ]
@@ -2173,18 +2173,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2 1.0.106",
  "quote 1.0.45",

Cargo.toml

@@ -98,7 +98,7 @@ rand = ["dep:rand"]
 [dependencies]
 anyhow = { version = "1.0.102", default-features = false }
 serde = {version = "1.0.150", default-features = false, features = ["derive", "rc", "alloc"] }
-serde_json = { version = "1.0.89", default-features = false, features = ["alloc"] }
+serde_json = { version = "1.0.150", default-features = false, features = ["alloc"] }
 hashbrown = { version = "0.17", default-features = false, features = ["default-hasher"], optional = true }
 lazy_static =  { version = "1.4.0", default-features = false }
 thiserror = { version = "2.0", default-features = false }
@@ -107,7 +107,7 @@ data-encoding = { version = "2.8.0", optional = true, default-features=false, fe
 num-bigint = { version = "0.4", default-features = false }
 num-traits = { version = "0.2", default-features = false }
 parking_lot = { version = "0.12", optional = true }
-spin = { version = "0.10.0", default-features = false, features = ["mutex", "spin_mutex"] }
+spin = { version = "0.12.0", default-features = false, features = ["mutex", "spin_mutex"] }
 
 globset = { version = "0.4.16", features = ["simd-accel"], default-features = false, optional = true }
 regex = {version = "1.12.3", optional = true, default-features = false }

bindings/ffi/Cargo.lock

@@ -98,9 +98,9 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bit-set"
@@ -141,9 +141,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -153,9 +153,9 @@ checksum = "175812e0be2bccb6abe50bb8d566126198344f707e304f45c648fd8f2cc0365e"
 
 [[package]]
 name = "cbindgen"
-version = "0.29.2"
+version = "0.29.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "befbfd072a8e81c02f8c507aefce431fe5e7d051f83d48a23ffc9b9fe5a11799"
+checksum = "c95537b45400390270fae69ac098d057c8f5399001cde9d04f700c105ddfff2d"
 dependencies = [
  "clap",
  "heck",
@@ -285,9 +285,9 @@ checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
 
 [[package]]
 name = "dashmap"
-version = "6.1.0"
+version = "6.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5041cc499144891f3790297212f32a74fb938e5136a14943f338ef9e0ae276cf"
+checksum = "e6361d5c062261c78a176addb82d4c821ae42bed6089de0e12603cd25de2059c"
 dependencies = [
  "cfg-if",
  "crossbeam-utils",
@@ -305,9 +305,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -712,9 +712,9 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -790,9 +790,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -802,9 +802,9 @@ checksum = "8a860605968fce16869fd239cf4237a82f3ac470723415db603b0e8b6c8d4fb9"
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -1255,9 +1255,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1314,9 +1314,9 @@ checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1426,7 +1426,7 @@ version = "1.1.2+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2abe9b86193656635d2411dc43050282ca48aa31c2451210f4202550afb7526"
 dependencies = [
- "winnow 1.0.2",
+ "winnow 1.0.3",
 ]
 
 [[package]]
@@ -1535,9 +1535,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1548,9 +1548,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -1558,9 +1558,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2",
@@ -1571,9 +1571,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
@@ -1688,9 +1688,9 @@ checksum = "df79d97927682d2fd8adb29682d1140b343be4ac0f08fd68b7765d9c059d3945"
 
 [[package]]
 name = "winnow"
-version = "1.0.2"
+version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2ee1708bef14716a11bae175f579062d4554d95be2c6829f518df847b7b3fdd0"
+checksum = "0592e1c9d151f854e6fd382574c3a0855250e1d9b2f99d9281c6e6391af352f1"
 
 [[package]]
 name = "wit-bindgen"
@@ -1817,18 +1817,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1837,9 +1837,9 @@ dependencies = [
 
 [[package]]
 name = "zerofrom"
-version = "0.1.7"
+version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "69faa1f2a1ea75661980b013019ed6687ed0e83d069bc1114e2cc74c6c04c4df"
+checksum = "0ec05a11813ea801ff6d75110ad09cd0824ddba17dfe17128ea0d5f68e6c5272"
 dependencies = [
  "zerofrom-derive",
 ]

bindings/ffi/Cargo.toml

@@ -13,7 +13,7 @@ crate-type = ["cdylib", "staticlib"]
 [dependencies]
 anyhow = "1.0"
 regorus = { path  = "../..", default-features = false }
-serde_json = "1.0.140"
+serde_json = "1.0.150"
 parking_lot = { version = "0.12", optional = true }
 
 [profile.release]

bindings/java/Cargo.lock

@@ -48,9 +48,9 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bit-set"
@@ -91,9 +91,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -199,9 +199,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -598,9 +598,9 @@ dependencies = [
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -670,9 +670,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -682,9 +682,9 @@ checksum = "8a860605968fce16869fd239cf4237a82f3ac470723415db603b0e8b6c8d4fb9"
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -1128,9 +1128,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1194,9 +1194,9 @@ checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1360,9 +1360,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1373,9 +1373,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -1383,9 +1383,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2",
@@ -1396,9 +1396,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
@@ -1639,18 +1639,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2",
  "quote",

bindings/java/Cargo.toml

@@ -21,6 +21,6 @@ cache = ["regorus/cache"]
 
 [dependencies]
 anyhow = "1.0"
-serde_json = "1.0.112"
+serde_json = "1.0.150"
 jni = "0.22.4"
 regorus = { path  = "../..", default-features = false, features = ["arc", "rvm"] }

bindings/python/Cargo.lock

@@ -48,9 +48,9 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bit-set"
@@ -91,9 +91,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -183,9 +183,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -533,9 +533,9 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -605,9 +605,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -617,9 +617,9 @@ checksum = "8a860605968fce16869fd239cf4237a82f3ac470723415db603b0e8b6c8d4fb9"
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -837,9 +837,9 @@ dependencies = [
 
 [[package]]
 name = "pyo3"
-version = "0.28.3"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "91fd8e38a3b50ed1167fb981cd6fd60147e091784c427b8f7183a7ee32c31c12"
+checksum = "cd274650b21d4bfc26a0a47587962c1edb425f69287324355cd040c3ea66071c"
 dependencies = [
  "anyhow",
  "libc",
@@ -852,18 +852,18 @@ dependencies = [
 
 [[package]]
 name = "pyo3-build-config"
-version = "0.28.3"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e368e7ddfdeb98c9bca7f8383be1648fd84ab466bf2bc015e94008db6d35611e"
+checksum = "c5e2a7d2f0d013342f295c048ad19237add5154a55b1c5a254c0ec93d4109078"
 dependencies = [
  "target-lexicon",
 ]
 
 [[package]]
 name = "pyo3-ffi"
-version = "0.28.3"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f29e10af80b1f7ccaf7f69eace800a03ecd13e883acfacc1e5d0988605f651e"
+checksum = "ca85c467da1bbc8d866eea5deff9cf29ea5f7785054a17da36e65bda9c05845b"
 dependencies = [
  "libc",
  "pyo3-build-config",
@@ -871,9 +871,9 @@ dependencies = [
 
 [[package]]
 name = "pyo3-macros"
-version = "0.28.3"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "df6e520eff47c45997d2fc7dd8214b25dd1310918bbb2642156ef66a67f29813"
+checksum = "9ac53762fd065daa3194dd09337a38bd793a188100fd1a9304c4ab312d901771"
 dependencies = [
  "proc-macro2",
  "pyo3-macros-backend",
@@ -883,13 +883,12 @@ dependencies = [
 
 [[package]]
 name = "pyo3-macros-backend"
-version = "0.28.3"
+version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4cdc218d835738f81c2338f822078af45b4afdf8b2e33cbb5916f108b813acb"
+checksum = "4ca3a1557399783172dc5bf39cfca835157732532cba56b71d2292161e53b362"
 dependencies = [
  "heck",
  "proc-macro2",
- "pyo3-build-config",
  "quote",
  "syn",
 ]
@@ -1120,9 +1119,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1170,9 +1169,9 @@ checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1332,9 +1331,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1345,9 +1344,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -1355,9 +1354,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2",
@@ -1368,9 +1367,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
@@ -1593,18 +1592,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2",
  "quote",

bindings/python/Cargo.toml

@@ -23,7 +23,7 @@ coverage = ["regorus/coverage"]
 [dependencies]
 anyhow = "1.0"
 ordered-float = "5.3.0"
-pyo3 = { version = "0.28.3", features = ["abi3-py310", "anyhow", "extension-module"] }
+pyo3 = { version = "0.29.0", features = ["abi3-py310", "anyhow", "extension-module"] }
 regorus = { path  = "../..", default-features = false, features = ["arc", "rvm"] }
-serde_json = "1.0.140"
+serde_json = "1.0.150"
 

bindings/ruby/Cargo.lock

@@ -48,9 +48,9 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bindgen"
@@ -109,9 +109,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -212,9 +212,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -223,9 +223,9 @@ dependencies = [
 
 [[package]]
 name = "either"
-version = "1.15.0"
+version = "1.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+checksum = "91622ff5e7162018101f2fea40d6ebf4a78bbe5a49736a2020649edf9693679e"
 
 [[package]]
 name = "email_address"
@@ -571,9 +571,9 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -653,9 +653,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -688,9 +688,9 @@ dependencies = [
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -1162,9 +1162,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1229,9 +1229,9 @@ checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1391,9 +1391,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1404,9 +1404,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -1414,9 +1414,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2",
@@ -1427,9 +1427,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
@@ -1652,18 +1652,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2",
  "quote",

bindings/wasm/Cargo.lock

@@ -59,9 +59,9 @@ dependencies = [
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "bit-set"
@@ -102,9 +102,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "bytecount"
@@ -200,9 +200,9 @@ checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
 [[package]]
 name = "displaydoc"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -565,9 +565,9 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.98"
+version = "0.3.99"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67df7112613f8bfd9150013a0314e196f4800d3201ae742489d999db2f979f08"
+checksum = "142bc4740e452c1e57ade0cbc129f139c9093e354346f0872ef985f4f5cf5f11"
 dependencies = [
  "cfg-if",
  "futures-util",
@@ -643,9 +643,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.29"
+version = "0.4.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
+checksum = "616ec5685824bcc94416c6d4a7a446eea774a31efd7062c8480ba6fd06d7a6e5"
 
 [[package]]
 name = "lru"
@@ -655,9 +655,9 @@ checksum = "8a860605968fce16869fd239cf4237a82f3ac470723415db603b0e8b6c8d4fb9"
 
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "6b947ae49db0d222b1dbc6b113ce7248a3fc3a6ca21b696717bfc000ba4484d8"
 
 [[package]]
 name = "micromap"
@@ -1120,9 +1120,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "e8014e44b4736ed0538adeecded0fce2a272f22dc9578a7eb6b2d9993c74cfb9"
 dependencies = [
  "itoa",
  "memchr",
@@ -1170,9 +1170,9 @@ checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "spin"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5fe4ccb98d9c292d56fec89a5e07da7fc4cf0dc11e156b41793132775d3e591"
+checksum = "1527984ca054dfca79333baec451042863f485fbee01b7bf6d911de915cac865"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1344,9 +1344,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49ace1d07c165b0864824eee619580c4689389afa9dc9ed3a4c75040d82e6790"
+checksum = "3ed04576f974d2b2fba0f38c51dbc5518011e38c36bf1143164be765528fd409"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1357,9 +1357,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.71"
+version = "0.4.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96492d0d3ffba25305a7dc88720d250b1401d7edca02cc3bcd50633b424673b8"
+checksum = "9473dbd2991ae90b6291c3c32c30c6187ac49aa32f9905d1cce280ec1e110b0f"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -1367,9 +1367,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e68e6f4afd367a562002c05637acb8578ff2dea1943df76afb9e83d177c8578"
+checksum = "916151b09da36bd82f6615cbf3a419e2f0ba23a03c6160e8e92eb6bd4aa1dec6"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -1377,9 +1377,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d95a9ec35c64b2a7cb35d3fead40c4238d0940c86d107136999567a4703259f2"
+checksum = "299047362ccbfce148b67ab7e73349f77748e00c8296f9542adfad2ad82c5c5e"
 dependencies = [
  "bumpalo",
  "proc-macro2",
@@ -1390,18 +1390,18 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4e0100b01e9f0d03189a92b96772a1fb998639d981193d7dbab487302513441"
+checksum = "9a929b2c61f11ba3e9bc35b50c1f25cb38e0e892c0c231ae2b8cf78d5dad4437"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "wasm-bindgen-test"
-version = "0.3.71"
+version = "0.3.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af5ec93229ad9ccd0a545a516dec76dc276613f278f6a91aa6b463d5b33d42d0"
+checksum = "74fde991ccdc895cb7fbaa14b137d62af74d9011be67b71c694bfc40edd3119c"
 dependencies = [
  "async-trait",
  "cast",
@@ -1421,9 +1421,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-test-macro"
-version = "0.3.71"
+version = "0.3.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c81b9fef827e575e0e54431736d1baa0d700315d8c62cfef1f61fa3aad0cbeb"
+checksum = "e925354648d2a4d1bf205412e36d520a800280622eef4719678d268e5d40e978"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1432,9 +1432,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-test-shared"
-version = "0.2.121"
+version = "0.2.122"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f4d8ae7ad5440360e9799dfd42857d126454a88441ddf72d288ef83fa47f527"
+checksum = "684365b586a9a6256c1cc3544eee8680de48d6041142f581776ec7b139622ae9"
 
 [[package]]
 name = "wasm-encoder"
@@ -1672,18 +1672,18 @@ dependencies = [
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "bce33a6288fa3f072a8c2c7d0f2fdbb90e28298f0135c1f99b96c3db2efcc60b"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "8fd425244944f4ab65ccff928e7323354c5a018c75838362fdce749dfad2ee1e"
 dependencies = [
  "proc-macro2",
  "quote",

bindings/wasm/Cargo.toml

@@ -42,7 +42,7 @@ coverage = ["regorus/coverage"]
 [dependencies]
 regorus = { path  = "../..", default-features = false, features = ["arc", "rvm"] }
 serde = { version = "1.0.219", features = ["derive"] }
-serde_json = "1.0.140"
+serde_json = "1.0.150"
 wasm-bindgen = "0.2.100"
 serde-wasm-bindgen = "0.6"
 # Specify uuid as a mandatory dependency so as to enable `js` feature which is now required
@@ -55,7 +55,7 @@ getrandom03 = { package = "getrandom", version = "0.3.1", features = ["std", "wa
 getrandom = { version = "0.4.2", features = ["wasm_js"] }
 
 [dev-dependencies]
-wasm-bindgen-test = "0.3.71"
+wasm-bindgen-test = "0.3.72"
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(wasm_bindgen_unstable_test_coverage)'] }

docs/value/object.md

@@ -0,0 +1,84 @@
+# Object
+
+Opaque container for `Value::Object`'s key→value storage, enabling
+alternative backends without call-site changes.
+
+## Design
+
+`Object` wraps the storage for a key→value collection of `Value`s and
+provides a curated set of methods (`get`, `insert`, `remove`, `iter`,
+`iter_sorted`, `cursor`, serde). The backing store is private; callers
+never see or pattern-match on it, so the representation can change
+without rippling through call sites.
+
+Multiple backends can coexist at runtime. Because the backing store is
+private, different `Object` instances in the same process can use
+different implementations — e.g., a lazy DB-backed object for `input`,
+inline small-map objects for SARIF location records, and a regular
+sorted map elsewhere — all interoperating through the same opaque
+type. This is stronger than the typical Cargo-feature-selected backend
+seen in precedent crates.
+
+Iteration is split intentionally. `iter()` makes no ordering promise,
+which lets backends that don't keep entries sorted skip any sort work.
+`iter_sorted()` returns entries in `Value` order and is what
+serialization and `Ord` rely on for deterministic output. Cursor types
+add resumable, incremental traversal for the RVM iteration state
+without leaking iterator internals.
+
+`Ord` and `PartialOrd` are defined against `iter_sorted()` rather than
+derived from the storage. Two `Object`s built on different backends —
+or with different insertion histories — compare equal whenever their
+sorted entries match, so changing the backend never changes observable
+comparison results.
+
+## Precedents
+
+Other crates that hide storage behind a stable API so the implementation
+can change without breaking callers:
+
+- **`serde_json::Map`** — opaque newtype allowing cargo-feature based
+  swap between `BTreeMap` (canonical order) and `IndexMap` (insertion
+  order).
+- **`toml::Table`** — opaque newtype allowing cargo-feature based swap
+  between `BTreeMap` and `IndexMap`.
+- **`simdjson` DOM** — opaque tree that lazily materializes nodes on
+  access instead of parsing the whole document up front.
+
+## Use cases
+
+- **SARIF small-object pressure** — SARIF reports contain millions of
+  small objects (location records, rule references, message arguments),
+  most with 2-5 keys. A small-map-optimized backend (inline storage
+  for ≤N entries, heap above) eliminates per-object BTreeMap allocation
+  for the common case.
+
+- **Kubernetes admission policies** — large, deeply-nested resource
+  objects (Pod specs, CRDs) where policies typically touch a handful
+  of paths. A lazy-materializing backend (`LazyObjectProvider` over
+  the incoming JSON) parses only the accessed subtrees.
+
+- **Azure Policy aliases** — ARM exposes the same logical property
+  under multiple aliases (e.g. paths like
+  `Microsoft.Compute/virtualMachines/storageProfile.osDisk.managedDisk.id`).
+  An alias-aware backend resolves lookups across canonical and alias
+  forms without rewriting every policy.
+
+- **Azure Policy case-insensitive compare** — ARM property names are
+  case-preserving but case-insensitive on lookup (`tags.Environment`
+  and `tags.environment` resolve identically). A case-insensitive
+  backend centralizes this once at the storage layer instead of at
+  every comparison site.
+
+- **External data sources** — `input` or `data` backed by a database
+  query, CBOR slice, REST endpoint, or other streaming source via a
+  `LazyObjectProvider`. Entries materialize on demand; the policy
+  only pays for what it touches.
+
+- **Eval-time temporaries** — objects constructed during evaluation
+  (comprehensions, intermediate rule results) on a bumpalo arena.
+  The whole arena drops at query end with zero per-entry free cost.
+
+- **Host-language interop** — Python dicts or JS objects accessed via
+  FFI callbacks from the embedding application, without copying into
+  Rust on every binding boundary.

src/builtins/azure_policy/helpers.rs

@@ -319,7 +319,7 @@ pub fn resolve_path(root: &Value, path: &str) -> Value {
         match &current {
             Value::Object(map) => {
                 let mut next = None;
-                for (key, value) in map.iter() {
+                for (key, value) in map.iter_sorted() {
                     if let Value::String(ref key_str) = *key {
                         if strings::keys::eq(key_str, &segment) {
                             next = Some(value.clone());

src/builtins/azure_policy/template_functions_collection.rs

@@ -8,10 +8,10 @@
 use crate::ast::{Expr, Ref};
 use crate::builtins;
 use crate::lexer::Span;
+use crate::value::Object;
 use crate::value::Value;
 use crate::Rc;
 
-use alloc::collections::BTreeMap;
 use alloc::vec::Vec;
 use anyhow::Result;
 
@@ -72,7 +72,7 @@ fn fn_intersection(
             // Intersection of objects: keep key-value pairs from the first
             // object only when the key exists in every other object AND
             // the value is equal across all of them.
-            let mut result: BTreeMap<Value, Value> = first.as_ref().clone();
+            let mut result: Object = first.as_ref().clone();
             for arg in rest {
                 let Value::Object(ref other) = *arg else {
                     return Ok(Value::Undefined);
@@ -114,7 +114,7 @@ fn fn_union(_span: &Span, _params: &[Ref<Expr>], args: &[Value], _strict: bool)
         Value::Object(_) => {
             // Union of objects: recursive merge. Nested objects are merged
             // recursively; all other types (including arrays) use last-writer-wins.
-            let mut result = BTreeMap::<Value, Value>::new();
+            let mut result = Object::new();
             for arg in args {
                 let Value::Object(ref obj) = *arg else {
                     return Ok(Value::Undefined);
@@ -264,7 +264,7 @@ fn fn_create_object(
         );
     }
 
-    let mut map = BTreeMap::<Value, Value>::new();
+    let mut map = Object::new();
 
     for pair in args.chunks(2) {
         #[allow(clippy::pattern_type_mismatch)]
@@ -280,9 +280,9 @@ fn fn_create_object(
 
 /// Recursively merge two objects.  Nested objects are merged; everything
 /// else (including arrays) uses the value from `incoming`.
-fn merge_objects(base: &BTreeMap<Value, Value>, overlay: &BTreeMap<Value, Value>) -> Value {
+fn merge_objects(base: &Object, overlay: &Object) -> Value {
     let mut result = base.clone();
-    for (k, v) in overlay {
+    for (k, v) in overlay.iter() {
         #[allow(clippy::needless_borrowed_reference)]
         let merged = match (result.get(k), v) {
             (Some(&Value::Object(ref prev)), &Value::Object(ref next)) => merge_objects(prev, next),

src/builtins/azure_policy/template_functions_misc.rs

@@ -8,10 +8,10 @@
 use crate::ast::{Expr, Ref};
 use crate::builtins;
 use crate::lexer::Span;
+use crate::value::Object;
 use crate::value::Value;
 use crate::Rc;
 
-use alloc::collections::BTreeMap;
 use alloc::string::{String, ToString as _};
 use alloc::vec::Vec;
 use anyhow::Result;
@@ -84,8 +84,8 @@ fn fn_items(_span: &Span, _params: &[Ref<Expr>], args: &[Value], _strict: bool)
         return Ok(Value::Undefined);
     };
     let mut result = Vec::with_capacity(obj.len());
-    for (k, v) in obj.as_ref() {
-        let mut entry = BTreeMap::<Value, Value>::new();
+    for (k, v) in obj.iter_sorted() {
+        let mut entry = Object::new();
         entry.insert(Value::from("key"), k.clone());
         entry.insert(Value::from("value"), v.clone());
         result.push(Value::Object(Rc::new(entry)));

src/builtins/encoding.rs

@@ -308,7 +308,7 @@ fn urlquery_encode_object(
 
     {
         let mut pairs = url.query_pairs_mut();
-        for (key, value) in obj.iter() {
+        for (key, value) in obj.iter_sorted() {
             let key = ensure_string(name, &params[0], key)?;
             match value {
                 Value::String(v) => {

src/builtins/graph.rs

@@ -7,10 +7,11 @@ use crate::ast::{Expr, Ref};
 use crate::builtins;
 use crate::builtins::utils::{enforce_limit, ensure_args_count, ensure_object};
 use crate::lexer::Span;
+use crate::value::Object;
 use crate::value::Value;
 use crate::*;
 
-use alloc::collections::{BTreeMap, BTreeSet};
+use alloc::collections::BTreeSet;
 
 use anyhow::{bail, Result};
 
@@ -80,7 +81,7 @@ fn reachable(span: &Span, params: &[Ref<Expr>], args: &[Value], strict: bool) ->
 }
 
 fn visit(
-    graph: &BTreeMap<Value, Value>,
+    graph: &Object,
     visited: &mut BTreeSet<Value>,
     node: &Value,
     path: &mut Vec<Value>,
@@ -211,7 +212,7 @@ fn walk_visit(path: &mut Vec<Value>, value: &Value, paths: &mut Vec<Value>) -> R
             }
         }
         Value::Object(obj) => {
-            for (key, value) in obj.iter() {
+            for (key, value) in obj.iter_sorted() {
                 path.push(key.clone());
                 // Guard path stack growth while traversing object entries.
                 enforce_limit()?;

src/builtins/objects.rs

@@ -205,7 +205,7 @@ fn merge_filters(
                     let vref = match f {
                         Value::Object(obj) => {
                             let obj = Rc::make_mut(obj);
-                            let entry = obj.entry(p.clone()).or_insert_with(Value::new_object);
+                            let entry = obj.get_or_insert_with(p.clone(), Value::new_object);
                             // Guard filter map growth when creating nested objects.
                             enforce_limit()?;
                             entry

src/builtins/strings.rs

@@ -207,7 +207,7 @@ fn to_string(v: &Value, unescape: bool) -> String {
         }
         Value::Object(o) => {
             "{".to_owned()
-                + &o.iter()
+                + &o.iter_sorted()
                     .map(|(k, v)| to_string(k, true) + ": " + &to_string(v, true))
                     .collect::<Vec<String>>()
                     .join(", ")
@@ -568,7 +568,7 @@ fn replace_n(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -
     let mut s = ensure_string(name, &params[1], &args[1])?;
 
     let span = params[0].span();
-    for item in obj.as_ref().iter() {
+    for item in obj.as_ref().iter_sorted() {
         match item {
             (Value::String(k), Value::String(v)) => {
                 s = s.replace(k.as_ref(), v.as_ref()).into();

src/builtins/utils.rs

@@ -5,11 +5,12 @@
 use crate::ast::{Expr, Ref};
 use crate::lexer::Span;
 use crate::number::Number;
+use crate::value::Object;
 use crate::Rc;
 use crate::Value;
 use crate::*;
 
-use alloc::collections::{BTreeMap, BTreeSet};
+use alloc::collections::BTreeSet;
 
 use anyhow::{bail, Result};
 
@@ -168,7 +169,7 @@ pub fn ensure_set(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<BTreeSet<Value>>
     })
 }
 
-pub fn ensure_object(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<BTreeMap<Value, Value>>> {
+pub fn ensure_object(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<Object>> {
     Ok(match v {
         Value::Object(o) => o,
         _ => {

src/interpreter.rs

@@ -28,7 +28,6 @@ use crate::{Expression, Extension, Location, QueryResult, QueryResults};
 use crate::query::traversal::traverse;
 
 use crate::Rc;
-use alloc::collections::btree_map::Entry as BTreeMapEntry;
 use alloc::collections::{BTreeMap, BTreeSet};
 use anyhow::{anyhow, bail, Result};
 use core::ops::Bound::*;
@@ -1312,10 +1311,10 @@ impl Interpreter {
                                 *obj = Value::new_object();
                             }
 
-                            obj = obj
-                                .as_object_mut()?
-                                .entry(Value::String(p.to_string().into()))
-                                .or_insert(Value::new_object());
+                            obj = obj.as_object_mut()?.get_or_insert_with(
+                                Value::String(p.to_string().into()),
+                                Value::new_object,
+                            );
                         }
                         *obj = value;
                         // Mark modified rules as processed.
@@ -1682,8 +1681,7 @@ impl Interpreter {
                     let set = obj
                         .as_object_mut()
                         .map_err(|_| anyhow!(span.error("previous value is not an object")))?
-                        .entry(p)
-                        .or_insert(Value::new_set())
+                        .get_or_insert_with(p, Value::new_set)
                         .as_set_mut()
                         .map_err(|_| anyhow!(span.error("previous value is not a set")))?;
                     set.append(value.as_set_mut()?);
@@ -1691,20 +1689,13 @@ impl Interpreter {
                     let obj = obj
                         .as_object_mut()
                         .map_err(|_| anyhow!(span.error("previous value is not an object")))?;
-                    match obj.entry(p) {
-                        BTreeMapEntry::Vacant(v) => {
-                            if value != Value::Undefined {
-                                v.insert(value);
-                            } else {
-                                // TODO: clean this assumption between Undefined vs Object.
-                                v.insert(Value::new_object());
-                            }
-                        }
-                        BTreeMapEntry::Occupied(o) => {
-                            if o.get() != &value && value != Value::Undefined {
-                                bail!(span
-                                    .error("complete rules should not produce multiple outputs"))
-                            }
+                    if value == Value::Undefined {
+                        // TODO: clean this assumption between Undefined vs Object.
+                        obj.get_or_insert_with(p, Value::new_object);
+                    } else {
+                        let existing = obj.get_or_insert_with(p, || value.clone());
+                        if *existing != value {
+                            bail!(span.error("complete rules should not produce multiple outputs"))
                         }
                     }
                 }
@@ -1713,8 +1704,7 @@ impl Interpreter {
                 obj = obj
                     .as_object_mut()
                     .map_err(|_| anyhow!(span.error("previous value is not an object")))?
-                    .entry(p)
-                    .or_insert(Value::new_object());
+                    .get_or_insert_with(p, Value::new_object);
             }
         }
         Ok(())
@@ -1822,8 +1812,7 @@ impl Interpreter {
                     let set = ctx_mut
                         .rule_value
                         .as_object_mut()?
-                        .entry(Value::from_array(comps))
-                        .or_insert(Value::new_set());
+                        .get_or_insert_with(Value::from_array(comps), Value::new_set);
                     if output != Value::Undefined {
                         set.as_set_mut()?.insert(output);
                         return Ok(true);
@@ -1832,20 +1821,13 @@ impl Interpreter {
                 }
 
                 // Non-set rule.
-                match ctx_mut
-                    .rule_value
-                    .as_object_mut()?
-                    .entry(Value::from_array(comps))
-                {
-                    BTreeMapEntry::Vacant(v) => {
-                        v.insert(output);
-                    }
-                    BTreeMapEntry::Occupied(o) if o.get() != &output => bail!(rule_ref
+                let key = Value::from_array(comps);
+                let obj_mut = ctx_mut.rule_value.as_object_mut()?;
+                let existing = obj_mut.get_or_insert_with(key, || output.clone());
+                if *existing != output {
+                    bail!(rule_ref
                         .span()
-                        .error("rules must not produce multiple outputs")),
-                    _ => {
-                        // Rule produced same value.
-                    }
+                        .error("rules must not produce multiple outputs"));
                 }
 
                 return Ok(true);
@@ -2471,7 +2453,7 @@ impl Interpreter {
             }
             Value::Object(map) => {
                 s.push('{');
-                for (idx, (k, entry_value)) in map.iter().enumerate() {
+                for (idx, (k, entry_value)) in map.iter_sorted().enumerate() {
                     if idx > 0 {
                         s.push_str(", ");
                     }

src/languages/azure_policy/aliases/denormalizer/mod.rs

@@ -213,10 +213,10 @@ pub fn denormalize_with_aliases(
     // Phase 4: Attach properties to result.
     if !properties.is_empty() {
         if let Some(Value::Object(existing_rc)) = result.get_mut("properties") {
-            // Merge directly into the BTreeMap, avoiding full ObjMap round-trip.
+            // Merge directly into the Object, avoiding full ObjMap round-trip.
             let existing = Rc::make_mut(existing_rc);
             for (k, v) in properties {
-                existing.entry(Value::String(k)).or_insert(v);
+                existing.get_or_insert_with(Value::String(k), || v);
             }
         } else {
             obj_insert(&mut result, "properties", make_value(properties));

src/languages/azure_policy/aliases/denormalizer/sub_resource.rs

@@ -7,6 +7,7 @@ use alloc::collections::{BTreeMap, BTreeSet};
 use alloc::string::String;
 use alloc::vec::Vec;
 
+use crate::value::Object;
 use crate::Value;
 
 use super::super::obj_map::{make_value, new_map, obj_insert, val_str, ObjMap};
@@ -141,7 +142,7 @@ fn rewrap_nested_array(
 /// BTreeMap-native recursion for nested sub-resource array re-wrapping,
 /// avoiding ObjMap round-trips on each array element.
 fn rewrap_nested_array_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
+    btree: &mut Object,
     parent_parts: &[&str],
     array_name: &str,
     envelope_fields: &BTreeSet<String>,
@@ -187,10 +188,7 @@ fn rewrap_nested_array_in_btree(
 }
 
 /// Find a key in a BTreeMap using case-insensitive comparison.
-fn find_key_ci_btree(
-    btree: &alloc::collections::BTreeMap<Value, Value>,
-    key: &str,
-) -> Option<Value> {
+fn find_key_ci_btree(btree: &Object, key: &str) -> Option<Value> {
     btree
         .keys()
         .find(|k| val_str(k).is_some_and(|s| s.eq_ignore_ascii_case(key)))

src/languages/azure_policy/aliases/normalizer/element_remap.rs

@@ -6,11 +6,12 @@
 use alloc::string::String;
 use alloc::vec::Vec;
 
+use crate::value::Object;
 use crate::Value;
 
 use super::super::obj_map::{
-    obj_get, obj_get_mut, obj_insert, set_nested_in_btree, set_nested_lowercased,
-    set_nested_verbatim, ObjMap,
+    obj_get, obj_get_mut, obj_insert, set_nested, set_nested_lowercased, set_nested_verbatim,
+    ObjMap,
 };
 use super::super::types::PrecomputedRemap;
 
@@ -118,7 +119,7 @@ fn apply_remap_at_depth(
 /// BTreeMap-native recursion for element-level remap, avoiding ObjMap
 /// round-trips on each array element.
 fn remap_at_depth_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
+    btree: &mut Object,
     array_chain: &[Vec<String>],
     depth: usize,
     source_field: &str,
@@ -177,12 +178,7 @@ fn remap_at_depth_in_btree(
 }
 
 /// Remap a value between dotted paths directly in a BTreeMap.
-fn remap_deep_field_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
-    source: &str,
-    target: &str,
-    lowercase: bool,
-) {
+fn remap_deep_field_in_btree(btree: &mut Object, source: &str, target: &str, lowercase: bool) {
     let val = match read_dotted_path_btree(btree, source) {
         Some(v) => v,
         None => return,
@@ -198,14 +194,11 @@ fn remap_deep_field_in_btree(
         }
         return;
     }
-    set_nested_in_btree(btree, &segments, val, lowercase);
+    set_nested(btree, &segments, val, lowercase);
 }
 
 /// Read a value at a dotted path from a BTreeMap.
-fn read_dotted_path_btree(
-    btree: &alloc::collections::BTreeMap<Value, Value>,
-    path: &str,
-) -> Option<Value> {
+fn read_dotted_path_btree(btree: &Object, path: &str) -> Option<Value> {
     let segments: Vec<&str> = path.split('.').collect();
     let first = segments.first()?;
     let mut cur: &Value = btree.get(&Value::from(*first))?;

src/languages/azure_policy/aliases/normalizer/mod.rs

@@ -13,6 +13,7 @@ mod flatten;
 // Re-export items used by the denormalizer.
 pub(crate) use element_remap::{apply_element_remap, ElementRemap};
 
+use crate::value::Object;
 use crate::Value;
 
 use super::obj_map::{
@@ -109,7 +110,7 @@ pub fn normalize_with_aliases(
 /// Merge `properties` fields into the result map, skipping keys that already
 /// exist.
 fn merge_properties(
-    obj: &alloc::collections::BTreeMap<Value, Value>,
+    obj: &Object,
     result: &mut ObjMap,
     sub_arrays: Option<&alloc::collections::BTreeSet<alloc::string::String>>,
 ) {

src/languages/azure_policy/aliases/obj_map.rs

@@ -4,7 +4,7 @@
 //! Lightweight string-keyed map used during normalization/denormalization.
 //!
 //! Internally uses `hashbrown::HashMap<Rc<str>, Value>` for O(1) lookups,
-//! then converts to `Value::Object` (a `BTreeMap<Value, Value>`) only at
+//! then converts to `Value::Object` (an `Object`) only at
 //! the output boundary via [`make_value`].
 
 use alloc::string::String;
@@ -12,6 +12,7 @@ use alloc::vec::Vec;
 
 use hashbrown::HashMap;
 
+use crate::value::Object;
 use crate::Rc;
 use crate::Value;
 
@@ -81,14 +82,13 @@ pub fn obj_remove(map: &mut ObjMap, key: &str) -> Option<Value> {
 /// Convert an [`ObjMap`] into a [`Value::Object`].
 ///
 /// Keys are converted from `Rc<str>` to `Value::String` and inserted into
-/// a `BTreeMap` to match the `Value::Object` representation.
+/// an `Object` to match the `Value::Object` representation.
 pub fn make_value(map: ObjMap) -> Value {
-    use alloc::collections::BTreeMap;
-    let mut btree = BTreeMap::new();
-    for (k, v) in map {
-        btree.insert(Value::String(k), v);
-    }
-    Value::Object(Rc::new(btree))
+    let obj: Object = map
+        .into_iter()
+        .map(|(k, v)| (Value::String(k), v))
+        .collect();
+    Value::Object(Rc::new(obj))
 }
 
 /// Convert a `Vec<Value>` into a `Value::Array`.
@@ -115,14 +115,14 @@ pub fn extract_type_field(resource: &Value) -> Option<&str> {
     })
 }
 
-/// Convert a `Value::Object` (BTreeMap<Value, Value>) into an [`ObjMap`].
+/// Convert a `Value::Object` (Object) into an [`ObjMap`].
 ///
 /// Non-string keys are silently skipped.
 #[allow(dead_code)]
 pub fn value_to_obj_map(value: &Value) -> Option<ObjMap> {
-    let btree = value.as_object().ok()?;
-    let mut map = ObjMap::with_capacity(btree.len());
-    for (k, v) in btree.iter() {
+    let obj = value.as_object().ok()?;
+    let mut map = ObjMap::with_capacity(obj.len());
+    for (k, v) in obj.iter() {
         if let Value::String(s) = k {
             map.insert(Rc::clone(s), v.clone());
         }
@@ -194,7 +194,7 @@ fn set_nested_inner(obj: &mut ObjMap, segments: &[&str], value: Value, lowercase
     // Descend directly into the BTreeMap, avoiding ObjMap round-trip.
     if let Some(Value::Object(inner_rc)) = obj.get_mut(&*seg) {
         let inner_btree = Rc::make_mut(inner_rc);
-        set_nested_in_btree(
+        set_nested(
             inner_btree,
             segments.get(1..).unwrap_or_default(),
             value,
@@ -203,17 +203,12 @@ fn set_nested_inner(obj: &mut ObjMap, segments: &[&str], value: Value, lowercase
     }
 }
 
-/// Set a value at a path directly in a `BTreeMap<Value, Value>`, creating
+/// Set a value at a path directly in an `Object`, creating
 /// intermediate `Value::Object` nodes as needed.
 ///
 /// This avoids the `btree_to_obj_map` / `obj_map_to_btree` round-trip that
 /// would clone every sibling entry at each nesting level.
-pub fn set_nested_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
-    segments: &[&str],
-    value: Value,
-    lowercase: bool,
-) {
+pub fn set_nested(obj: &mut Object, segments: &[&str], value: Value, lowercase: bool) {
     let Some(&first) = segments.first() else {
         return;
     };
@@ -226,18 +221,18 @@ pub fn set_nested_in_btree(
     let key_val = Value::String(Rc::clone(&key_rc));
 
     if segments.len() == 1 {
-        btree.insert(key_val, value);
+        obj.insert(key_val, value);
         return;
     }
 
     // Ensure an intermediate object exists.
-    if !btree.contains_key(&key_val) {
-        btree.insert(key_val.clone(), make_value(new_map()));
+    if !obj.contains_key(&key_val) {
+        obj.insert(key_val.clone(), make_value(new_map()));
     }
 
-    if let Some(Value::Object(inner_rc)) = btree.get_mut(&key_val) {
+    if let Some(Value::Object(inner_rc)) = obj.get_mut(&key_val) {
         let inner = Rc::make_mut(inner_rc);
-        set_nested_in_btree(
+        set_nested(
             inner,
             segments.get(1..).unwrap_or_default(),
             value,
@@ -352,20 +347,15 @@ fn remove_field_at_depth(obj: &mut ObjMap, array_chain: &[Vec<String>], depth: u
         for elem in inner.iter_mut() {
             if let Value::Object(obj_rc) = elem {
                 let inner_btree = Rc::make_mut(obj_rc);
-                remove_field_at_depth_in_btree(
-                    inner_btree,
-                    array_chain,
-                    depth.saturating_add(1),
-                    field,
-                );
+                remove_field_at_depth_obj(inner_btree, array_chain, depth.saturating_add(1), field);
             }
         }
     }
 }
 
-/// BTreeMap-native recursion for element-level field removal.
-fn remove_field_at_depth_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
+/// Object-native recursion for element-level field removal.
+fn remove_field_at_depth_obj(
+    obj: &mut Object,
     array_chain: &[Vec<String>],
     depth: usize,
     field: &str,
@@ -374,10 +364,10 @@ fn remove_field_at_depth_in_btree(
         let segments: Vec<&str> = field.split('.').collect();
         if segments.len() == 1 {
             if let Some(&seg) = segments.first() {
-                btree.remove(&Value::from(seg));
+                obj.remove(&Value::from(seg));
             }
         } else if segments.len() > 1 {
-            remove_at_dotted_path_in_btree(btree, &segments);
+            remove_at_dotted_path_obj(obj, &segments);
         }
         return;
     };
@@ -389,12 +379,12 @@ fn remove_field_at_depth_in_btree(
 
     let key_val = Value::from(first);
     let arr_val = if nav.len() == 1 {
-        match btree.get_mut(&key_val) {
+        match obj.get_mut(&key_val) {
             Some(v) => v,
             None => return,
         }
     } else {
-        let mut cur: &mut Value = match btree.get_mut(&key_val) {
+        let mut cur: &mut Value = match obj.get_mut(&key_val) {
             Some(v) => v,
             None => return,
         };
@@ -415,27 +405,19 @@ fn remove_field_at_depth_in_btree(
         for elem in inner.iter_mut() {
             if let Value::Object(obj_rc) = elem {
                 let inner_btree = Rc::make_mut(obj_rc);
-                remove_field_at_depth_in_btree(
-                    inner_btree,
-                    array_chain,
-                    depth.saturating_add(1),
-                    field,
-                );
+                remove_field_at_depth_obj(inner_btree, array_chain, depth.saturating_add(1), field);
             }
         }
     }
 }
 
-/// Remove the leaf segment at a dotted path directly in a BTreeMap.
-fn remove_at_dotted_path_in_btree(
-    btree: &mut alloc::collections::BTreeMap<Value, Value>,
-    segments: &[&str],
-) {
+/// Remove the leaf segment at a dotted path directly in an Object.
+fn remove_at_dotted_path_obj(obj: &mut Object, segments: &[&str]) {
     let Some((&leaf, parent_segs)) = segments.split_last() else {
         return;
     };
     if parent_segs.is_empty() {
-        btree.remove(&Value::from(leaf));
+        obj.remove(&Value::from(leaf));
         return;
     }
 
@@ -443,7 +425,7 @@ fn remove_at_dotted_path_in_btree(
         return;
     };
     let first_key = Value::from(first);
-    let parent_val = match btree.get_mut(&first_key) {
+    let parent_val = match obj.get_mut(&first_key) {
         Some(v) => v,
         None => return,
     };

src/languages/azure_policy/compiler/effects.rs

@@ -11,7 +11,7 @@
 //! to fetch a related resource and an optional `existenceCondition` evaluated
 //! inline.
 
-use alloc::collections::BTreeMap;
+use crate::value::Object;
 use alloc::format;
 use alloc::string::ToString as _;
 use alloc::vec::Vec;
@@ -814,7 +814,7 @@ pub(super) fn build_object_from_keys(
     span: &crate::lexer::Span,
 ) -> Result<u8> {
     // Build template: object with all keys set to Undefined.
-    let mut template = BTreeMap::new();
+    let mut template = Object::new();
     for &(key_idx, _) in &keys {
         // key_idx was returned by `add_literal_u16` in the calling code,
         // so it is always in bounds.  We use `.get()` + `?` instead of

src/languages/azure_policy/compiler/metadata.rs

@@ -272,7 +272,7 @@ impl Compiler {
 fn insert_string_set_annotation(
     annot: &mut alloc::collections::BTreeMap<String, Value>,
     key: &str,
-    observed: &BTreeSet<String>,
+    observed: &alloc::collections::BTreeSet<String>,
 ) {
     if !observed.is_empty() {
         let set: BTreeSet<Value> = observed

src/languages/rego/compiler/expressions/collection_literals.rs

@@ -11,8 +11,9 @@ use crate::ast::{Expr, ExprRef};
 use crate::lexer::Span;
 use crate::rvm::instructions::{ArrayCreateParams, ObjectCreateParams, SetCreateParams};
 use crate::rvm::Instruction;
+use crate::value::Object;
 use crate::{Rc, Value};
-use alloc::collections::{BTreeMap, BTreeSet};
+use alloc::collections::BTreeSet;
 use alloc::vec::Vec;
 
 /// Try to evaluate an expression as a compile-time constant.
@@ -43,7 +44,7 @@ pub(in crate::languages::rego::compiler) fn try_eval_const(expr: &Expr) -> Optio
         Expr::Object { fields, .. } => fields
             .iter()
             .map(|(_, k, v)| Some((try_eval_const(k.as_ref())?, try_eval_const(v.as_ref())?)))
-            .collect::<Option<BTreeMap<_, _>>>()
+            .collect::<Option<Object>>()
             .map(|m| Value::Object(Rc::new(m))),
         _ => None,
     }
@@ -117,7 +118,7 @@ impl<'a> Compiler<'a> {
         fields: &[(crate::lexer::Span, ExprRef, ExprRef)],
         span: &Span,
     ) -> Result<Register> {
-        let all_const: Option<BTreeMap<_, _>> = fields
+        let all_const: Option<Object> = fields
             .iter()
             .map(|(_, k, v)| Some((try_eval_const(k.as_ref())?, try_eval_const(v.as_ref())?)))
             .collect();
@@ -166,7 +167,7 @@ impl<'a> Compiler<'a> {
             let mut template_keys = literal_keys.clone();
             template_keys.sort();
 
-            let mut template_obj = BTreeMap::new();
+            let mut template_obj = Object::new();
             for key in &template_keys {
                 template_obj.insert(key.clone(), Value::Undefined);
             }

src/lib.rs

@@ -155,7 +155,7 @@ pub mod target;
 #[cfg(any(test, all(feature = "yaml", feature = "std")))]
 pub mod test_utils;
 pub mod utils;
-mod value;
+pub mod value;
 
 #[cfg(feature = "azure_policy")]
 pub use {

src/rvm/program/metadata.rs

@@ -11,9 +11,9 @@
 //! values are converted through [`MetadataValue`] — a postcard/bincode-safe
 //! enum that avoids `deserialize_any`.
 
+use crate::value::Object;
 use crate::Rc;
-use alloc::collections::BTreeMap;
-use alloc::collections::BTreeSet;
+use alloc::collections::{BTreeMap, BTreeSet};
 use alloc::string::String;
 use alloc::vec::Vec;
 use serde::{Deserialize, Serialize};
@@ -52,7 +52,7 @@ impl ProgramMetadata {
     pub fn to_value(&self) -> crate::value::Value {
         use crate::value::Value;
 
-        let mut obj = BTreeMap::new();
+        let mut obj = Object::new();
         obj.insert(
             Value::String("compiler_version".into()),
             Value::String(self.compiler_version.as_str().into()),
@@ -75,7 +75,7 @@ impl ProgramMetadata {
         );
 
         if !self.annotations.is_empty() {
-            let mut annotations_obj = BTreeMap::new();
+            let mut annotations_obj = Object::new();
             for (k, v) in &self.annotations {
                 annotations_obj.insert(Value::String(k.as_str().into()), v.clone());
             }
@@ -198,7 +198,7 @@ impl MetadataValue {
         match *self {
             MetadataValue::String(ref s) => Value::String(s.as_str().into()),
             MetadataValue::StringSet(ref set) => {
-                let mut bset = alloc::collections::BTreeSet::new();
+                let mut bset = BTreeSet::new();
                 for s in set {
                     bset.insert(Value::String(s.as_str().into()));
                 }
@@ -211,7 +211,7 @@ impl MetadataValue {
                 Value::Array(Rc::new(values))
             }
             MetadataValue::Map(ref map) => {
-                let mut obj = BTreeMap::new();
+                let mut obj = Object::new();
                 for (k, v) in map {
                     obj.insert(Value::String(k.as_str().into()), v.to_value());
                 }
@@ -257,7 +257,6 @@ mod metadata_serde {
 mod tests {
     use super::*;
     use crate::value::Value;
-    use alloc::collections::BTreeSet;
 
     /// Round-trip: Value → MetadataValue → Value must be equivalent for
     /// all lossless variants (strings, bools, integers, arrays, objects).

src/rvm/program/serialization/value.rs

@@ -1,6 +1,6 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
-use alloc::collections::{BTreeMap, BTreeSet};
+use alloc::collections::BTreeSet;
 use alloc::format;
 use alloc::string::String;
 use alloc::vec::Vec;
@@ -11,6 +11,7 @@ use serde::ser::{SerializeSeq as _, SerializeTuple as _};
 use serde::{Deserialize, Serialize};
 
 use crate::number::Number;
+use crate::value::Object;
 use crate::value::Value;
 
 const VARIANT_NULL: u32 = 0;
@@ -132,7 +133,7 @@ impl<'a> Serialize for BinarySetRef<'a> {
     }
 }
 
-struct BinaryObjectRef<'a>(&'a BTreeMap<Value, Value>);
+struct BinaryObjectRef<'a>(&'a Object);
 
 impl<'a> Serialize for BinaryObjectRef<'a> {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
@@ -140,7 +141,7 @@ impl<'a> Serialize for BinaryObjectRef<'a> {
         S: serde::Serializer,
     {
         let mut seq = serializer.serialize_seq(Some(self.0.len()))?;
-        for (key, value) in self.0.iter() {
+        for (key, value) in self.0.iter_sorted() {
             seq.serialize_element(&BinaryEntryRef(key, value))?;
         }
         seq.end()
@@ -261,11 +262,11 @@ impl<'de> Visitor<'de> for BinaryValueVisitor {
             }
             (BinaryVariant::Object, variant) => {
                 let entries: Vec<(BinaryValue, BinaryValue)> = variant.newtype_variant()?;
-                let mut map = BTreeMap::new();
+                let mut map = Object::new();
                 for (key, value) in entries {
                     map.insert(key.into_value(), value.into_value());
                 }
-                Ok(BinaryValue(Value::from(map)))
+                Ok(BinaryValue(Value::Object(crate::Rc::new(map))))
             }
             (BinaryVariant::Undefined, variant) => {
                 variant.unit_variant()?;

src/rvm/vm/arithmetic.rs

@@ -6,8 +6,6 @@
 // Disable both to keep patterns consistent within this file.
 #![allow(clippy::pattern_type_mismatch, clippy::needless_borrowed_reference)]
 
-use alloc::collections::BTreeSet;
-
 use crate::number::Number;
 use crate::value::Value;
 
@@ -32,8 +30,9 @@ impl RegoVM {
         match (a, b) {
             (&Value::Number(ref x), &Value::Number(ref y)) => Ok(Value::from(x.sub(y)?)),
             (&Value::Set(ref left), &Value::Set(ref right)) => {
-                let diff: BTreeSet<Value> = left.difference(right).cloned().collect();
-                Ok(Value::from_set(diff))
+                let diff: alloc::collections::BTreeSet<Value> =
+                    left.difference(right).cloned().collect();
+                Ok(Value::from(diff))
             }
             _ => Err(VmError::InvalidSubtraction {
                 left: a.clone(),

src/rvm/vm/comprehension.rs

@@ -2,9 +2,9 @@
 // Licensed under the MIT License.
 
 use crate::rvm::instructions::{ComprehensionBeginParams, ComprehensionMode};
+use crate::value::Object;
 use crate::value::Value;
 use crate::Rc;
-use alloc::collections::BTreeMap;
 use alloc::format;
 use alloc::sync::Arc;
 use alloc::vec::Vec;
@@ -34,12 +34,12 @@ impl RegoVM {
         let initial_result = match params.mode {
             ComprehensionMode::Set => Value::new_set(),
             ComprehensionMode::Array => Value::new_array(),
-            ComprehensionMode::Object => Value::Object(Rc::new(BTreeMap::new())),
+            ComprehensionMode::Object => Value::Object(Rc::new(Object::new())),
         };
         self.set_register(params.result_reg, initial_result.clone())?;
 
         let auto_iterate = params.collection_reg != params.result_reg;
-        let iteration_state = if auto_iterate {
+        let mut iteration_state = if auto_iterate {
             let source_value = self.get_register(params.collection_reg)?.clone();
             match source_value {
                 Value::Array(items) => {
@@ -53,11 +53,9 @@ impl RegoVM {
                     if obj.is_empty() {
                         None
                     } else {
-                        Some(IterationState::Object {
-                            obj,
-                            current_key: None,
-                            first_iteration: true,
-                        })
+                        // O(1) cursor over shared Rc<Object>.
+                        let cursor = obj.cursor();
+                        Some(IterationState::Object { obj, cursor })
                     }
                 }
                 Value::Set(set) => {
@@ -79,7 +77,7 @@ impl RegoVM {
             None
         };
 
-        let has_iteration = if let Some(state) = iteration_state.as_ref() {
+        let has_iteration = if let Some(state) = iteration_state.as_mut() {
             self.setup_next_iteration(state, params.key_reg, params.value_reg)?
         } else {
             false
@@ -123,12 +121,12 @@ impl RegoVM {
         let initial_result = match params.mode {
             ComprehensionMode::Set => Value::new_set(),
             ComprehensionMode::Array => Value::new_array(),
-            ComprehensionMode::Object => Value::Object(Rc::new(BTreeMap::new())),
+            ComprehensionMode::Object => Value::Object(Rc::new(Object::new())),
         };
         self.set_register(params.result_reg, initial_result.clone())?;
 
         let auto_iterate = params.collection_reg != params.result_reg;
-        let iteration_state = if auto_iterate {
+        let mut iteration_state = if auto_iterate {
             let source_value = self.get_register(params.collection_reg)?.clone();
             match source_value {
                 Value::Array(items) => {
@@ -142,11 +140,8 @@ impl RegoVM {
                     if obj.is_empty() {
                         None
                     } else {
-                        Some(IterationState::Object {
-                            obj,
-                            current_key: None,
-                            first_iteration: true,
-                        })
+                        let cursor = obj.cursor();
+                        Some(IterationState::Object { obj, cursor })
                     }
                 }
                 Value::Set(set) => {
@@ -168,7 +163,7 @@ impl RegoVM {
             None
         };
 
-        let has_iteration = if let Some(state) = iteration_state.as_ref() {
+        let has_iteration = if let Some(state) = iteration_state.as_mut() {
             self.setup_next_iteration(state, params.key_reg, params.value_reg)?
         } else {
             false
@@ -255,6 +250,21 @@ impl RegoVM {
         };
 
         let result_reg = comprehension_context.result_reg;
+        // Snapshot the iteration value register BEFORE taking the result
+        // register: if the comprehension compiler ever allocates
+        // `result_reg == context.value_reg`, the writeback at the bottom
+        // of this function would clobber the value register, and a
+        // post-writeback read here would feed the wrong value into
+        // `IterationState::Set::current_item`. Only Set needs the snapshot
+        // (Object uses a self-advancing cursor; Array advances by index).
+        let set_resume_snapshot = if matches!(
+            comprehension_context.iteration_state,
+            Some(IterationState::Set { .. })
+        ) {
+            Some(self.get_register(comprehension_context.value_reg)?.clone())
+        } else {
+            None
+        };
         // Take ownership of the result register so Rc refcount stays at 1,
         // allowing Rc::make_mut to mutate in-place instead of deep-cloning.
         let mut current_result = self.take_register(result_reg)?;
@@ -292,29 +302,16 @@ impl RegoVM {
         self.set_register(result_reg, current_result)?;
 
         if let Some(iter_state) = comprehension_context.iteration_state.as_mut() {
-            match *iter_state {
-                IterationState::Object {
-                    ref mut current_key,
-                    ..
-                } => {
-                    let tracked_key =
-                        if comprehension_context.key_reg != comprehension_context.value_reg {
-                            self.get_register(comprehension_context.key_reg)?.clone()
-                        } else {
-                            self.get_register(comprehension_context.value_reg)?.clone()
-                        };
-                    *current_key = Some(tracked_key);
-                }
-                IterationState::Set {
-                    ref mut current_item,
-                    ..
-                } => {
-                    *current_item =
-                        Some(self.get_register(comprehension_context.value_reg)?.clone());
-                }
-                IterationState::Array { .. } | IterationState::Single { .. } => {}
+            // Set's `Bound::Excluded(current_item)` resume scheme needs the
+            // pre-mutation snapshot taken at the top of this function.
+            // Object uses a self-advancing cursor and needs no snapshot.
+            if let IterationState::Set {
+                ref mut current_item,
+                ..
+            } = *iter_state
+            {
+                *current_item = set_resume_snapshot;
             }
-
             iter_state.advance();
             let has_next = self.setup_next_iteration(
                 iter_state,
@@ -359,8 +356,7 @@ impl RegoVM {
             result_reg_idx,
             key_reg_idx,
             value_reg_idx,
-            iteration_key,
-            iteration_value,
+            iter_is_set,
         ) = {
             let frame =
                 self.execution_stack
@@ -382,8 +378,8 @@ impl RegoVM {
 
                 let result_reg_idx = context.result_reg;
                 let mode = context.mode.clone();
-                let iteration_key = self.get_register(context.key_reg)?.clone();
-                let iteration_value = self.get_register(context.value_reg)?.clone();
+                let iter_is_set =
+                    matches!(context.iteration_state, Some(IterationState::Set { .. }));
 
                 (
                     value_to_add,
@@ -392,8 +388,7 @@ impl RegoVM {
                     result_reg_idx,
                     context.key_reg,
                     context.value_reg,
-                    iteration_key,
-                    iteration_value,
+                    iter_is_set,
                 )
             } else {
                 return Err(VmError::InvalidIteration {
@@ -403,6 +398,18 @@ impl RegoVM {
             }
         };
 
+        // Snapshot the iteration value register BEFORE the result writeback:
+        // if the compiler ever allocates `result_reg == value_reg_idx`, a
+        // post-writeback read would feed the result accumulator into
+        // `IterationState::Set::current_item`, breaking the next iteration.
+        // Only Set needs this (Object cursor self-advances; Array advances
+        // by index).
+        let set_resume_snapshot = if iter_is_set {
+            Some(self.get_register(value_reg_idx)?.clone())
+        } else {
+            None
+        };
+
         // Take ownership of the result register so Rc refcount stays at 1,
         // allowing Rc::make_mut to mutate in-place instead of deep-cloning.
         let mut current_result = self.take_register(result_reg_idx)?;
@@ -450,27 +457,13 @@ impl RegoVM {
             } = &mut frame.kind
             {
                 if let Some(iter_state) = context.iteration_state.as_mut() {
-                    match *iter_state {
-                        IterationState::Object {
-                            ref mut current_key,
-                            ..
-                        } => {
-                            let tracked_key = if context.key_reg != context.value_reg {
-                                iteration_key.clone()
-                            } else {
-                                iteration_value.clone()
-                            };
-                            *current_key = Some(tracked_key);
-                        }
-                        IterationState::Set {
-                            ref mut current_item,
-                            ..
-                        } => {
-                            *current_item = Some(iteration_value.clone());
-                        }
-                        IterationState::Array { .. } | IterationState::Single { .. } => {}
+                    if let IterationState::Set {
+                        ref mut current_item,
+                        ..
+                    } = *iter_state
+                    {
+                        *current_item = set_resume_snapshot;
                     }
-
                     iter_state.advance();
                 }
 
@@ -487,8 +480,21 @@ impl RegoVM {
             }
         };
 
-        if let Some(state) = iteration_state_snapshot.as_ref() {
-            let has_next = self.setup_next_iteration(state, key_reg_idx, value_reg_idx)?;
+        if let Some(mut state) = iteration_state_snapshot {
+            let has_next = self.setup_next_iteration(&mut state, key_reg_idx, value_reg_idx)?;
+
+            // `setup_next_iteration` advances Object's internal cursor; the
+            // owning frame holds the iteration_state, so we must write the
+            // updated state back. (The Array/Set variants are also unchanged
+            // by copy, so the writeback is uniform.)
+            if let Some(frame) = self.execution_stack.get_mut(comprehension_index) {
+                if let FrameKind::Comprehension {
+                    ref mut context, ..
+                } = frame.kind
+                {
+                    context.iteration_state = Some(state);
+                }
+            }
 
             if has_next {
                 if let Some(frame) = self.execution_stack.get_mut(comprehension_index) {
@@ -528,7 +534,6 @@ impl RegoVM {
             Ok(false)
         }
     }
-
     pub(super) fn handle_comprehension_condition_failure_suspendable(&mut self) -> Result<bool> {
         if let Some(mut frame) = self.execution_stack.pop() {
             let handled = if let &mut FrameKind::Comprehension {
@@ -554,11 +559,16 @@ impl RegoVM {
         context: &mut ComprehensionContext,
     ) -> Result<()> {
         if let Some(iter_state) = context.iteration_state.as_mut() {
-            self.capture_comprehension_iteration_position(
-                iter_state,
-                context.key_reg,
-                context.value_reg,
-            )?;
+            // Snapshot the current value into Set's `current_item` so the
+            // next iteration can resume from `Bound::Excluded(current)`.
+            // Object uses a self-advancing cursor and needs no snapshot here.
+            if let IterationState::Set {
+                ref mut current_item,
+                ..
+            } = *iter_state
+            {
+                *current_item = Some(self.get_register(context.value_reg)?.clone());
+            }
             iter_state.advance();
             let has_next =
                 self.setup_next_iteration(iter_state, context.key_reg, context.value_reg)?;
@@ -575,37 +585,10 @@ impl RegoVM {
         Ok(())
     }
 
-    fn capture_comprehension_iteration_position(
-        &mut self,
-        iter_state: &mut IterationState,
-        key_reg: u8,
-        value_reg: u8,
-    ) -> Result<()> {
-        match *iter_state {
-            IterationState::Object {
-                ref mut current_key,
-                ..
-            } => {
-                let tracked_key = if key_reg != value_reg {
-                    self.get_register(key_reg)?.clone()
-                } else {
-                    self.get_register(value_reg)?.clone()
-                };
-                *current_key = Some(tracked_key);
-            }
-            IterationState::Set {
-                ref mut current_item,
-                ..
-            } => {
-                *current_item = Some(self.get_register(value_reg)?.clone());
-            }
-            IterationState::Array { .. } | IterationState::Single { .. } => {}
-        }
-
-        Ok(())
-    }
-
     fn execute_comprehension_end_run_to_completion(&mut self) -> Result<()> {
+        // `ComprehensionEnd` is reached from a loaded program; an empty stack
+        // here means malformed user-supplied bytecode, which must still surface
+        // as a typed error rather than a panic — including in debug builds.
         self.comprehension_stack.pop().map_or_else(
             || {
                 Err(VmError::InvalidIteration {

src/rvm/vm/context.rs

@@ -3,8 +3,9 @@
 
 use crate::rvm::instructions::{ComprehensionMode, LoopMode};
 use crate::value::Value;
+use crate::value::{Object, ObjectCursor};
 use crate::Rc;
-use alloc::collections::{BTreeMap, BTreeSet};
+use alloc::collections::BTreeSet;
 use alloc::vec::Vec;
 
 /// Loop execution context for managing iteration state
@@ -24,7 +25,18 @@ pub struct LoopContext {
     pub current_iteration_failed: bool, // Track if current iteration had condition failures
 }
 
-/// Iterator state for different collection types
+/// Iterator state for different collection types.
+///
+/// Snapshot independence for `Object` is provided by the shared
+/// `Rc<Object>` — `Rc::make_mut` on an aliased Rc allocates a new
+/// collection, leaving the iterator's Rc pointing at the original
+/// pre-mutation state. The `ObjectCursor` is opaque and resumes in
+/// O(log n) for the BTree backend.
+///
+/// `Set` continues to use the pre-existing snapshot-by-cloned-key
+/// approach (`current_item` + `first_iteration`); migration of `Set`
+/// to a cursor-based iterator ships with the `Set` storage abstraction
+/// in a follow-up PR.
 #[derive(Debug, Clone)]
 pub enum IterationState {
     Array {
@@ -32,9 +44,8 @@ pub enum IterationState {
         index: usize,
     },
     Object {
-        obj: Rc<BTreeMap<Value, Value>>,
-        current_key: Option<Value>,
-        first_iteration: bool,
+        obj: Rc<Object>,
+        cursor: ObjectCursor,
     },
     Set {
         items: Rc<BTreeSet<Value>>,
@@ -54,13 +65,21 @@ impl IterationState {
     pub(super) const fn advance(&mut self) {
         match *self {
             Self::Array { ref mut index, .. } => {
+                // Array iteration uses `usize` as the cursor and advances via
+                // `saturating_add(1)`. A cursor already at `usize::MAX` here
+                // means a stuck (non-progressing) iteration was emitted by
+                // malformed bytecode; assert in debug to surface it loudly.
+                debug_assert!(
+                    *index < usize::MAX,
+                    "IterationState::Array index already at usize::MAX on advance"
+                );
                 *index = index.saturating_add(1);
             }
-            Self::Object {
-                ref mut first_iteration,
-                ..
-            }
-            | Self::Set {
+            // For Object the cursor advances inside `setup_next_iteration`
+            // when it pulls the next item via `Object::next`, so `advance`
+            // is a no-op for the cursor-backed Object variant.
+            Self::Object { .. } => {}
+            Self::Set {
                 ref mut first_iteration,
                 ..
             } => {
@@ -69,6 +88,12 @@ impl IterationState {
             Self::Single {
                 ref mut consumed, ..
             } => {
+                // `Single` yields exactly once; advancing a consumed Single
+                // means the compiler emitted a redundant LoopNext.
+                debug_assert!(
+                    !*consumed,
+                    "IterationState::Single advanced after consumption"
+                );
                 *consumed = true;
             }
         }
@@ -107,3 +132,71 @@ pub(super) struct ComprehensionContext {
     /// Resume location for the parent frame once this comprehension completes
     pub(super) resume_pc: usize,
 }
+
+#[cfg(test)]
+#[allow(
+    clippy::expect_used,
+    clippy::unwrap_used,
+    clippy::unreachable,
+    clippy::pattern_type_mismatch,
+    clippy::shadow_unrelated,
+    clippy::panic
+)]
+mod tests {
+    use super::*;
+    use crate::value::Object;
+
+    /// IterationState::Object holds an `Rc<Object>` plus an opaque cursor.
+    /// Mutating an aliased Rc via `Rc::make_mut` allocates a new collection
+    /// (CoW) so the in-flight iterator's source is unaffected.
+    #[test]
+    fn iteration_state_object_is_snapshot_independent_of_source() {
+        let mut obj = Object::new();
+        obj.insert(Value::from("a"), Value::from(1));
+        obj.insert(Value::from("b"), Value::from(2));
+        obj.insert(Value::from("c"), Value::from(3));
+
+        let source = Value::Object(Rc::new(obj));
+
+        let snapshot_obj = match &source {
+            Value::Object(o) => Rc::clone(o),
+            _ => unreachable!(),
+        };
+        let state = IterationState::Object {
+            obj: Rc::clone(&snapshot_obj),
+            cursor: snapshot_obj.cursor(),
+        };
+
+        // Mutate a clone of the source mid-iteration.
+        let mut alias = source.clone();
+        let inner = alias.as_object_mut().expect("object");
+        inner.insert(Value::from("a"), Value::from(999));
+        inner.insert(Value::from("d"), Value::from(4));
+        inner.remove(&Value::from("b"));
+
+        // Drain the snapshot via the cursor — must still report the original
+        // 3 entries with original values.
+        let mut collected: Vec<(Value, Value)> = Vec::new();
+        if let IterationState::Object {
+            ref obj,
+            mut cursor,
+        } = state
+        {
+            while let Some((k, v)) = obj.next(&mut cursor) {
+                collected.push((k.clone(), v.clone()));
+            }
+        } else {
+            unreachable!();
+        }
+        assert_eq!(collected.len(), 3);
+        assert!(collected.contains(&(Value::from("a"), Value::from(1))));
+        assert!(collected.contains(&(Value::from("b"), Value::from(2))));
+        assert!(collected.contains(&(Value::from("c"), Value::from(3))));
+        assert!(!collected.iter().any(|kv| kv.0 == Value::from("d")));
+
+        // The original source Value (untouched) is also unchanged.
+        let src_obj = source.as_object().expect("object");
+        assert_eq!(src_obj.len(), 3);
+        assert_eq!(src_obj.get(&Value::from("a")), Some(&Value::from(1)));
+    }
+}

src/rvm/vm/dispatch.rs

@@ -4,7 +4,6 @@
 use crate::rvm::instructions::{GuardMode, Instruction, LiteralOrRegister};
 use crate::rvm::program::Program;
 use crate::value::Value;
-use alloc::collections::BTreeSet;
 use alloc::vec::Vec;
 use core::mem;
 
@@ -670,7 +669,7 @@ impl RegoVM {
                 }
             }
             SetNew { dest } => {
-                let empty_set = Value::Set(crate::Rc::new(BTreeSet::new()));
+                let empty_set = Value::new_set();
                 self.set_register(dest, empty_set)?;
                 Ok(InstructionOutcome::Continue)
             }
@@ -707,7 +706,7 @@ impl RegoVM {
                     if any_undefined {
                         self.set_register(params.dest, Value::Undefined)?;
                     } else {
-                        let mut set = BTreeSet::new();
+                        let mut set = alloc::collections::BTreeSet::new();
                         for &reg in params.element_registers() {
                             set.insert(self.get_register(reg)?.clone());
                         }

src/rvm/vm/errors.rs

@@ -295,6 +295,13 @@ pub enum VmError {
     #[error("Call rule stack underflow during rule finalization (pc={pc})")]
     CallRuleStackUnderflow { pc: usize },
 
+    #[error("Call rule stack mismatch during rule finalization: expected rule_index {expected}, popped {actual} (pc={pc})")]
+    CallRuleStackMismatch {
+        expected: u16,
+        actual: u16,
+        pc: usize,
+    },
+
     #[error("Internal VM error: {message} (pc={pc})")]
     Internal { message: String, pc: usize },
 }

src/rvm/vm/execution.rs

@@ -117,6 +117,10 @@ impl RegoVM {
         let target = self.convert_pc(target, "jump target")?;
         self.pc = target;
         while self.pc < program.instructions.len() {
+            // Per-instruction sanity check: every iteration of the dispatch
+            // loop must re-enter with the VM in a Running/Ready state and the
+            // working data structures coherent.
+            self.assert_vm_invariants();
             self.memory_check()?;
             if self.executed_instructions >= self.max_instructions {
                 return Err(VmError::InstructionLimitExceeded {
@@ -189,6 +193,9 @@ impl RegoVM {
     }
 
     fn execute_suspendable_entry(&mut self, entry_point_pc: usize) -> Result<Value> {
+        // Precondition: callers (execute_entry_point_by_{index,name}) reset the
+        // VM before invoking this method, so the VM must be in a clean state.
+        self.debug_assert_state_is_clean();
         self.execution_state = ExecutionState::Running;
         self.reset_execution_timer_state();
         match self.run_stackless_from(entry_point_pc) {
@@ -201,6 +208,10 @@ impl RegoVM {
     }
 
     pub fn resume(&mut self, resume_value: Option<Value>) -> Result<Value> {
+        // Precondition is enforced below by returning `VmError::InvalidResumeState`
+        // for any non-`Suspended` state. A `debug_assert!` here would diverge
+        // debug vs release behavior and, when invoked via FFI, would trip the
+        // unwind guard and poison the engine on a recoverable misuse.
         let (reason, mut last_result) = match self.execution_state.clone() {
             ExecutionState::Suspended {
                 reason,
@@ -289,6 +300,9 @@ impl RegoVM {
 
     fn run_stackless_loop(&mut self, program: &Program, last_result: &mut Value) -> Result<()> {
         while !self.execution_stack.is_empty() {
+            // Per-instruction sanity check: see `assert_vm_invariants` for the
+            // exact contract. Compiled out in release.
+            self.assert_vm_invariants();
             self.memory_check()?;
             self.frame_pc_overridden = false;
             let should_finalize_rule = self.execution_stack.last().is_some_and(|frame| {

src/rvm/vm/loops.rs

@@ -3,6 +3,7 @@
 
 use crate::rvm::instructions::LoopMode;
 use crate::value::Value;
+use crate::Rc;
 
 use super::context::{IterationState, LoopContext};
 use super::errors::{Result, VmError};
@@ -89,13 +90,13 @@ impl RegoVM {
     ) -> Result<()> {
         self.set_register(params.result_reg, Value::Bool(false))?;
 
-        let iteration_state = match self.resolve_iteration_state(mode, &params)? {
+        let mut iteration_state = match self.resolve_iteration_state(mode, &params)? {
             Some(state) => state,
             None => return Ok(()),
         };
 
         let has_next =
-            self.setup_next_iteration(&iteration_state, params.key_reg, params.value_reg)?;
+            self.setup_next_iteration(&mut iteration_state, params.key_reg, params.value_reg)?;
         if !has_next {
             self.pc = usize::from(params.loop_end);
             return Ok(());
@@ -155,15 +156,10 @@ impl RegoVM {
                 LoopAction::Continue => {}
             }
 
-            if let &mut IterationState::Object {
-                ref mut current_key,
-                ..
-            } = &mut loop_ctx.iteration_state
-            {
-                if loop_ctx.key_reg != loop_ctx.value_reg {
-                    *current_key = Some(self.get_register(loop_ctx.key_reg)?.clone());
-                }
-            } else if let &mut IterationState::Set {
+            // Snapshot the current value for Set so its next iteration can resume
+            // from `Bound::Excluded(current)`. Object uses a cursor and advances
+            // inside `setup_next_iteration` itself.
+            if let &mut IterationState::Set {
                 ref mut current_item,
                 ..
             } = &mut loop_ctx.iteration_state
@@ -173,7 +169,7 @@ impl RegoVM {
 
             loop_ctx.iteration_state.advance();
             let has_next = self.setup_next_iteration(
-                &loop_ctx.iteration_state,
+                &mut loop_ctx.iteration_state,
                 loop_ctx.key_reg,
                 loop_ctx.value_reg,
             )?;
@@ -211,13 +207,13 @@ impl RegoVM {
     ) -> Result<()> {
         self.set_register(params.result_reg, Value::Bool(false))?;
 
-        let iteration_state = match self.resolve_iteration_state(mode, &params)? {
+        let mut iteration_state = match self.resolve_iteration_state(mode, &params)? {
             Some(state) => state,
             None => return Ok(()),
         };
 
         let has_next =
-            self.setup_next_iteration(&iteration_state, params.key_reg, params.value_reg)?;
+            self.setup_next_iteration(&mut iteration_state, params.key_reg, params.value_reg)?;
         if !has_next {
             self.pc = usize::from(params.loop_end);
             return Ok(());
@@ -316,7 +312,14 @@ impl RegoVM {
                 Ok(())
             }
             LoopAction::Continue => {
-                let (mode, success_count, total_iterations, key_reg, value_reg, iteration_state) = {
+                let (
+                    mode,
+                    success_count,
+                    total_iterations,
+                    key_reg,
+                    value_reg,
+                    mut iteration_state,
+                ) = {
                     let (mode, success_count, total_iterations, key_reg, value_reg) = {
                         let frame = self
                             .execution_stack
@@ -334,11 +337,6 @@ impl RegoVM {
                         }
                     };
 
-                    let key_value = if key_reg != value_reg {
-                        Some(self.get_register(key_reg)?.clone())
-                    } else {
-                        None
-                    };
                     let value_value = self.get_register(value_reg)?.clone();
 
                     let frame = self
@@ -349,20 +347,16 @@ impl RegoVM {
                         &mut FrameKind::Loop {
                             ref mut context, ..
                         } => {
-                            if let &mut IterationState::Object {
-                                ref mut current_key,
-                                ..
-                            } = &mut context.iteration_state
-                            {
-                                if context.key_reg != context.value_reg {
-                                    *current_key = key_value;
-                                }
-                            } else if let &mut IterationState::Set {
+                            // Snapshot the current value for Set so its next
+                            // iteration can resume from `Bound::Excluded(current)`.
+                            // Object uses a cursor and advances inside
+                            // `setup_next_iteration` itself.
+                            if let &mut IterationState::Set {
                                 ref mut current_item,
                                 ..
                             } = &mut context.iteration_state
                             {
-                                *current_item = Some(value_value.clone());
+                                *current_item = Some(value_value);
                             }
 
                             context.iteration_state.advance();
@@ -381,7 +375,21 @@ impl RegoVM {
                     }
                 };
 
-                let has_next = self.setup_next_iteration(&iteration_state, key_reg, value_reg)?;
+                let has_next =
+                    self.setup_next_iteration(&mut iteration_state, key_reg, value_reg)?;
+
+                // `setup_next_iteration` advances Object's internal cursor;
+                // the owning frame holds the iteration_state, so we must
+                // write the updated state back. (Array/Set are unchanged by
+                // the call, so the writeback is uniform.)
+                if let Some(frame) = self.execution_stack.last_mut() {
+                    if let FrameKind::Loop {
+                        ref mut context, ..
+                    } = frame.kind
+                    {
+                        context.iteration_state = iteration_state;
+                    }
+                }
 
                 if has_next {
                     if let Some(frame) = self.execution_stack.last_mut() {
@@ -459,10 +467,14 @@ impl RegoVM {
                         self.handle_empty_collection(mode, params.result_reg, params.loop_end)?;
                         return Ok(None);
                     }
+                    // O(1) resumable cursor over the shared Rc<Object>.
+                    // No eager pair snapshot: avoids O(N) setup, O(N) memory
+                    // floor, and O(N) memory-limit checks. Snapshot
+                    // independence is via the shared Rc (CoW).
+                    let cursor = obj.cursor();
                     Ok(Some(IterationState::Object {
-                        obj: obj.clone(),
-                        current_key: None,
-                        first_iteration: true,
+                        obj: Rc::clone(obj),
+                        cursor,
                     }))
                 }
             }
@@ -512,7 +524,7 @@ impl RegoVM {
 
     pub(super) fn setup_next_iteration(
         &mut self,
-        state: &IterationState,
+        state: &mut IterationState,
         key_reg: u8,
         value_reg: u8,
     ) -> Result<bool> {
@@ -538,33 +550,19 @@ impl RegoVM {
             }
             IterationState::Object {
                 ref obj,
-                ref current_key,
-                ref first_iteration,
+                ref mut cursor,
             } => {
-                if *first_iteration {
-                    if let Some((key, value)) = obj.iter().next() {
-                        if key_reg != value_reg {
-                            self.set_register(key_reg, key.clone())?;
-                        }
-                        self.set_register(value_reg, value.clone())?;
-                        Ok(true)
-                    } else {
-                        Ok(false)
-                    }
-                } else if let Some(ref current) = *current_key {
-                    let mut range_iter = obj.range((
-                        core::ops::Bound::Excluded(current),
-                        core::ops::Bound::Unbounded,
-                    ));
-                    if let Some((key, value)) = range_iter.next() {
-                        if key_reg != value_reg {
-                            self.set_register(key_reg, key.clone())?;
-                        }
-                        self.set_register(value_reg, value.clone())?;
-                        Ok(true)
-                    } else {
-                        Ok(false)
+                // Object iterates via a resumable cursor on the shared
+                // `Rc<Object>`; `next` both yields the current entry and
+                // advances the cursor. No explicit `current_key` snapshot is
+                // needed — see the doc on `IterationState`.
+                if let Some((key, value)) = obj.next(cursor) {
+                    let value = value.clone();
+                    if key_reg != value_reg {
+                        self.set_register(key_reg, key.clone())?;
                     }
+                    self.set_register(value_reg, value)?;
+                    Ok(true)
                 } else {
                     Ok(false)
                 }

src/rvm/vm/rules.rs

@@ -277,6 +277,19 @@ impl RegoVM {
             .call_rule_stack
             .pop()
             .ok_or(VmError::CallRuleStackUnderflow { pc: self.pc })?;
+        // Stack discipline: the context we just popped must belong to the
+        // rule we are finalizing. A mismatch indicates a missing push or an
+        // extra pop somewhere in this rule's execution and would otherwise
+        // silently restore the wrong return_pc / rule_type. Surface as a
+        // typed VmError so the contract holds the same in debug and release
+        // builds (avoiding FFI poisoning via a debug-only panic).
+        if rule_index != call_context.rule_index {
+            return Err(VmError::CallRuleStackMismatch {
+                expected: rule_index,
+                actual: call_context.rule_index,
+                pc: self.pc,
+            });
+        }
         self.pc = call_context.return_pc;
 
         let result_from_rule = if !rule_failed_due_to_inconsistency {
@@ -831,6 +844,9 @@ impl RegoVM {
 
         self.registers = parent_registers;
 
+        // Underflow here means malformed/poisoned program state; surface as a
+        // typed error rather than a debug-only panic so the public load_program
+        // contract holds the same in debug and release.
         if self.call_rule_stack.pop().is_none() {
             return Err(VmError::CallRuleStackUnderflow { pc: self.pc });
         }

src/rvm/vm/state.rs

@@ -34,6 +34,139 @@ impl RegoVM {
 
         // Builtin cache entries only live for a single execution
         self.builtins_cache.clear();
+
+        // Postcondition: every stack/cache that `reset_execution_state` touches
+        // must be in its documented "clean" shape. This catches accidental
+        // omissions in future edits to this function.
+        self.debug_assert_state_is_clean();
+    }
+
+    /// Debug-only postcondition for `reset_execution_state`.
+    ///
+    /// Asserts the invariants every caller of `reset_execution_state` relies on
+    /// before starting a fresh execution. The body is fully gated by
+    /// `#[cfg(debug_assertions)]` so this is a zero-cost no-op in release.
+    #[inline]
+    pub(super) fn debug_assert_state_is_clean(&self) {
+        #[cfg(debug_assertions)]
+        {
+            // --- Stacks: every per-execution stack must be drained. ---
+            debug_assert!(
+                self.execution_stack.is_empty(),
+                "reset_execution_state postcondition: execution_stack must be empty"
+            );
+            debug_assert!(
+                self.loop_stack.is_empty(),
+                "reset_execution_state postcondition: loop_stack must be empty"
+            );
+            debug_assert!(
+                self.comprehension_stack.is_empty(),
+                "reset_execution_state postcondition: comprehension_stack must be empty"
+            );
+            debug_assert!(
+                self.call_rule_stack.is_empty(),
+                "reset_execution_state postcondition: call_rule_stack must be empty"
+            );
+            debug_assert!(
+                self.register_stack.is_empty(),
+                "reset_execution_state postcondition: register_stack must be empty"
+            );
+
+            // --- Caches: cleared so a new program/input cannot read stale entries. ---
+            debug_assert!(
+                self.builtins_cache.is_empty(),
+                "reset_execution_state postcondition: builtins_cache must be empty"
+            );
+
+            // --- Registers: window resized to the program's base count and zeroed. ---
+            debug_assert_eq!(
+                self.registers.len(),
+                self.base_register_count,
+                "reset_execution_state postcondition: registers must be sized to base_register_count"
+            );
+            debug_assert!(
+                self.registers.iter().all(|v| matches!(v, Value::Undefined)),
+                "reset_execution_state postcondition: all registers must be Undefined"
+            );
+
+            // --- Rule cache: sized to the current program and marked uncomputed. ---
+            debug_assert_eq!(
+                self.rule_cache.len(),
+                self.program.rule_infos.len(),
+                "reset_execution_state postcondition: rule_cache size must match program rule_infos"
+            );
+            debug_assert!(
+                self.rule_cache.iter().all(|entry| !entry.0),
+                "reset_execution_state postcondition: rule_cache entries must be uncomputed"
+            );
+
+            // --- Counters and execution-state machine: zeroed and back to Ready. ---
+            debug_assert_eq!(
+                self.pc, 0,
+                "reset_execution_state postcondition: pc must be 0"
+            );
+            debug_assert_eq!(
+                self.executed_instructions, 0,
+                "reset_execution_state postcondition: executed_instructions must be 0"
+            );
+            debug_assert!(
+                matches!(self.execution_state, ExecutionState::Ready),
+                "reset_execution_state postcondition: execution_state must be Ready"
+            );
+        }
+    }
+
+    /// Per-opcode VM invariants checked from the inner dispatch loop.
+    ///
+    /// These hold every time control re-enters the dispatch loop with another
+    /// instruction to execute. Only conditions that are *purely VM-internal*
+    /// (i.e. cannot be made false by any host-supplied program or out-of-order
+    /// API call) are asserted here — anything reachable from `load_program`
+    /// input must surface as a typed `VmError` instead, to avoid panicking in
+    /// debug builds and poisoning the engine across FFI.
+    ///
+    /// Fully `#[cfg(debug_assertions)]`-gated so the method body compiles out
+    /// in release.
+    #[inline]
+    pub(super) fn assert_vm_invariants(&self) {
+        #[cfg(debug_assertions)]
+        {
+            // The dispatch loop only runs while execution is live. Once the VM
+            // has transitioned to a terminal state (Suspended/Completed/Error)
+            // the loop must have exited. Note `Ready` is also valid here because
+            // some entry points (e.g. `execute_entry_point_by_index` in
+            // RunToCompletion mode) drive `jump_to` without flipping the state.
+            // `execution_state` is mutated only inside the VM and is not
+            // host-controllable.
+            debug_assert!(
+                matches!(
+                    self.execution_state,
+                    ExecutionState::Ready | ExecutionState::Running
+                ),
+                "vm invariant: execution_state must be Ready or Running inside the dispatch loop, was {:?}",
+                self.execution_state
+            );
+
+            // Rule cache is sized once at reset (against the currently loaded
+            // program) and the VM does not resize it mid-execution. Any
+            // mismatch here would indicate an internal accounting bug rather
+            // than malformed input.
+            debug_assert_eq!(
+                self.rule_cache.len(),
+                self.program.rule_infos.len(),
+                "vm invariant: rule_cache size must equal program.rule_infos size"
+            );
+
+            // NOTE: `!registers.is_empty()` and an `execution_stack` depth
+            // ceiling were intentionally *not* asserted here: both can be
+            // triggered by a host-loaded program (registers via
+            // `RuleInfo::num_registers == 0`; stack depth via deeply nested
+            // rules/loops/comprehensions) and would therefore panic in debug
+            // and poison the engine across FFI. Register access is already
+            // guarded by `VmError::RegisterIndexOutOfBounds`; runaway recursion
+            // is bounded in production by `set_max_instructions` and
+            // `memory_check`.
+        }
     }
 
     /// Return all active objects to their respective pools for reuse

src/scheduler.rs

@@ -569,7 +569,7 @@ impl Analyzer {
                         }
                         Ok(false)
                     }
-                    Array { .. } | Object { .. } => Ok(true),
+                    Expr::Array { .. } | Expr::Object { .. } => Ok(true),
                     _ => Ok(false),
                 })?;
                 Ok(true)
@@ -666,7 +666,7 @@ impl Analyzer {
                 Ok(false)
             }
             // TODO: key vs value for object binding
-            Array { .. } | Object { .. } => Ok(true),
+            Expr::Array { .. } | Expr::Object { .. } => Ok(true),
             _ => Ok(false),
         })?;
         Ok(vars)
@@ -853,7 +853,7 @@ impl Analyzer {
                 Ok(false)
             }
             // TODO: Object key/value
-            Array { .. } | Object { .. } => Ok(true),
+            Expr::Array { .. } | Expr::Object { .. } => Ok(true),
             _ => {
                 non_vars.push(e.clone());
                 Ok(false)

src/schema/tests/suite.rs

@@ -1498,7 +1498,7 @@ fn test_deserialize_object_default_empty_object() {
     let s = Schema::from_serde_json_value(schema).unwrap();
     match s.as_type() {
         Type::Object { default, .. } => {
-            assert_eq!(default, &Some(Value::Object(Rc::new(BTreeMap::new()))));
+            assert_eq!(default, &Some(Value::new_object()));
         }
         _ => panic!("Expected Type::Object"),
     }
@@ -1778,8 +1778,11 @@ fn test_deserialize_enum_values_with_object_non_string_keys() {
     match s.as_type() {
         Type::Enum { values, .. } => match &values[0] {
             Value::Object(obj) => {
-                assert_eq!(obj[&Value::from("1")], Value::from("one"));
-                assert_eq!(obj[&Value::from("true")], Value::from("bool"));
+                assert_eq!(*obj.get(&Value::from("1")).expect("1"), Value::from("one"));
+                assert_eq!(
+                    *obj.get(&Value::from("true")).expect("true"),
+                    Value::from("bool")
+                );
             }
             _ => panic!("Expected object in enum values"),
         },
@@ -1802,18 +1805,21 @@ fn test_deserialize_enum_values_with_deeply_nested_structures() {
     match s.as_type() {
         Type::Enum { values, .. } => match &values[0] {
             Value::Object(obj) => {
-                let a = &obj[&Value::from("a")];
+                let a = obj.get(&Value::from("a")).expect("a");
                 match a {
                     Value::Array(arr) => match &arr[0] {
                         Value::Object(inner) => {
-                            let b = &inner[&Value::from("b")];
+                            let b = inner.get(&Value::from("b")).expect("b");
                             match b {
                                 Value::Array(barr) => {
                                     assert_eq!(barr[0], Value::from(1));
                                     assert_eq!(barr[1], Value::from(2));
                                     match &barr[2] {
                                         Value::Object(cobj) => {
-                                            assert_eq!(cobj[&Value::from("c")], Value::Null);
+                                            assert_eq!(
+                                                *cobj.get(&Value::from("c")).expect("c"),
+                                                Value::Null
+                                            );
                                         }
                                         _ => panic!("Expected object for 'c'"),
                                     }
@@ -1886,8 +1892,11 @@ fn test_deserialize_const_value_object() {
     match s.as_type() {
         Type::Const { value, .. } => match value {
             Value::Object(ref obj) => {
-                assert_eq!(obj[&Value::from("foo")], Value::from("bar"));
-                assert_eq!(obj[&Value::from("baz")], Value::from(1));
+                assert_eq!(
+                    *obj.get(&Value::from("foo")).expect("foo"),
+                    Value::from("bar")
+                );
+                assert_eq!(*obj.get(&Value::from("baz")).expect("baz"), Value::from(1));
             }
             _ => panic!("Expected object for const value"),
         },
@@ -1940,13 +1949,13 @@ fn test_deserialize_const_value_deeply_nested() {
     match s.as_type() {
         Type::Const { value, .. } => match value {
             Value::Object(ref obj) => {
-                let a = &obj[&Value::from("a")];
+                let a = obj.get(&Value::from("a")).expect("a");
                 match a {
                     Value::Array(arr) => {
                         assert_eq!(arr[0], Value::from(1));
                         match &arr[1] {
                             Value::Object(inner) => {
-                                let b = &inner[&Value::from("b")];
+                                let b = inner.get(&Value::from("b")).expect("b");
                                 match b {
                                     Value::Array(barr) => {
                                         assert_eq!(barr[0], Value::Null);

src/schema/validate.rs

@@ -7,6 +7,7 @@
 
 use crate::{
     schema::{error::ValidationError, Schema, Type},
+    value::Object,
     *,
 };
 use alloc::collections::BTreeMap;
@@ -537,7 +538,7 @@ impl SchemaValidator {
     }
 
     fn validate_discriminated_subobject_with_base(
-        object_value: &BTreeMap<Value, Value>,
+        object_value: &Object,
         discriminated_subobject: &crate::schema::DiscriminatedSubobject,
         base_properties: &BTreeMap<String, Schema>,
         base_additional_properties: Option<&Schema>,
@@ -653,7 +654,7 @@ impl SchemaValidator {
     }
 
     fn validate_subobject(
-        object_value: &BTreeMap<Value, Value>,
+        object_value: &Object,
         subobject: &crate::schema::Subobject,
         path: &str,
     ) -> Result<(), ValidationError> {

src/value/mod.rs

@@ -11,6 +11,18 @@
     clippy::as_conversions
 )] // value helpers index paths directly for performance
 
+mod object;
+
+#[cfg(test)]
+mod tests;
+
+#[allow(unused_imports)] // surface for downstream PRs
+pub use object::{IntoIter, Iter, IterMut, Object};
+
+#[cfg(feature = "rvm")]
+#[allow(unused_imports)] // surface for downstream PRs
+pub use object::ObjectCursor;
+
 use crate::number::Number;
 
 use alloc::collections::{BTreeMap, BTreeSet};
@@ -23,7 +35,7 @@ use core::str::FromStr;
 
 use anyhow::{anyhow, bail, Result};
 use serde::de::{self, Deserializer, Error as DeError, MapAccess, SeqAccess, Visitor};
-use serde::ser::{SerializeMap, Serializer};
+use serde::ser::Serializer;
 use serde::{Deserialize, Serialize};
 
 use crate::*;
@@ -63,7 +75,7 @@ pub enum Value {
 
     /// An object.
     /// Unlike JSON, keys can be any value, not just string.
-    Object(Rc<BTreeMap<Value, Value>>),
+    Object(Rc<Object>),
 
     /// Undefined value.
     /// Used to indicate the absence of a value.
@@ -86,26 +98,15 @@ impl Serialize for Value {
     where
         S: Serializer,
     {
-        use serde::ser::Error;
         match self {
             Value::Null => serializer.serialize_unit(),
             Value::Bool(b) => serializer.serialize_bool(*b),
             Value::String(s) => serializer.serialize_str(s.as_ref()),
             Value::Number(n) => n.serialize(serializer),
             Value::Array(a) => a.serialize(serializer),
-            Value::Object(fields) => {
-                let mut map = serializer.serialize_map(Some(fields.len()))?;
-                for (k, v) in fields.iter() {
-                    match k {
-                        Value::String(_) => map.serialize_entry(k, v)?,
-                        _ => {
-                            let key_str = serde_json::to_string(k).map_err(Error::custom)?;
-                            map.serialize_entry(&key_str, v)?
-                        }
-                    }
-                }
-                map.end()
-            }
+            // Delegate to the Object/Set serializers — single canonical path,
+            // handles non-string-key stringification internally.
+            Value::Object(fields) => fields.serialize(serializer),
 
             // display set as an array
             Value::Set(s) => s.serialize(serializer),
@@ -345,7 +346,7 @@ impl Value {
     /// assert_eq!(array[4], Value::from(12345u64));
     /// let obj = array[5].as_object().expect("not an object");
     /// assert_eq!(obj.len(), 1);
-    /// assert_eq!(obj[&Value::from("name")], Value::from("regorus"));
+    /// assert_eq!(obj.get(&Value::from("name")).expect("missing name"), &Value::from("regorus"));
     /// # Ok(())
     /// # }
     /// ```
@@ -800,7 +801,7 @@ impl From<BTreeMap<Value, Value>> for Value {
     /// # Ok(())
     /// # }
     fn from(s: BTreeMap<Value, Value>) -> Self {
-        Value::Object(Rc::new(s))
+        Value::Object(Rc::new(Object::from(s)))
     }
 }
 
@@ -1279,16 +1280,16 @@ impl Value {
         }
     }
 
-    /// Cast value to [`& BTreeMap<Value, Value>`] if [`Value::Object`].
+    /// Cast value to [`&Object`] if [`Value::Object`].
     /// ```
     /// # use regorus::*;
-    /// # use std::collections::BTreeMap;
+    /// # use regorus::value::Object;
     /// # fn main() -> anyhow::Result<()> {
     /// let v = Value::from(
     ///    [(Value::from("Hello"), Value::from("World"))]
     ///        .iter()
     ///        .cloned()
-    ///        .collect::<BTreeMap<Value, Value>>(),
+    ///        .collect::<Object>(),
     /// );
     /// assert_eq!(
     ///    v.as_object()?.iter().next(),
@@ -1296,28 +1297,28 @@ impl Value {
     /// );
     /// # Ok(())
     /// # }
-    pub fn as_object(&self) -> Result<&BTreeMap<Value, Value>> {
+    pub fn as_object(&self) -> Result<&Object> {
         match self {
             Value::Object(m) => Ok(m),
             _ => Err(anyhow!("not an object")),
         }
     }
 
-    /// Cast value to [`&mut BTreeMap<Value, Value>`] if [`Value::Object`].
+    /// Cast value to [`&mut Object`] if [`Value::Object`].
     /// ```
     /// # use regorus::*;
-    /// # use std::collections::BTreeMap;
+    /// # use regorus::value::Object;
     /// # fn main() -> anyhow::Result<()> {
     /// let mut v = Value::from(
     ///    [(Value::from("Hello"), Value::from("World"))]
     ///        .iter()
     ///        .cloned()
-    ///        .collect::<BTreeMap<Value, Value>>(),
+    ///        .collect::<Object>(),
     /// );
     /// v.as_object_mut()?.insert(Value::from("Good"), Value::from("Bye"));
     /// # Ok(())
     /// # }
-    pub fn as_object_mut(&mut self) -> Result<&mut BTreeMap<Value, Value>> {
+    pub fn as_object_mut(&mut self) -> Result<&mut Object> {
         match self {
             Value::Object(m) => Ok(Rc::make_mut(m)),
             _ => Err(anyhow!("not an object")),

src/value/object/iter.rs

@@ -0,0 +1,148 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+//! Opaque iterator types for [`Object`].
+//!
+//! These newtypes wrap the storage backend's iterators so the backend can be
+//! swapped without changing any iterator type signatures observed by callers.
+
+use alloc::collections::btree_map;
+use core::iter::FusedIterator;
+
+use super::Object;
+use crate::value::Value;
+
+/// Owned iterator over `(Value, Value)` entries.
+#[derive(Debug)]
+pub struct IntoIter {
+    pub(super) inner: btree_map::IntoIter<Value, Value>,
+}
+
+impl Iterator for IntoIter {
+    type Item = (Value, Value);
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next()
+    }
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+impl DoubleEndedIterator for IntoIter {
+    #[inline]
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.inner.next_back()
+    }
+}
+
+impl ExactSizeIterator for IntoIter {
+    #[inline]
+    fn len(&self) -> usize {
+        self.inner.len()
+    }
+}
+
+impl FusedIterator for IntoIter {}
+
+/// Borrowed iterator over `(&Value, &Value)` entries.
+#[derive(Debug, Clone)]
+pub struct Iter<'a> {
+    pub(super) inner: btree_map::Iter<'a, Value, Value>,
+}
+
+impl<'a> Iterator for Iter<'a> {
+    type Item = (&'a Value, &'a Value);
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next()
+    }
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+impl<'a> DoubleEndedIterator for Iter<'a> {
+    #[inline]
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.inner.next_back()
+    }
+}
+
+impl<'a> ExactSizeIterator for Iter<'a> {
+    #[inline]
+    fn len(&self) -> usize {
+        self.inner.len()
+    }
+}
+
+impl<'a> FusedIterator for Iter<'a> {}
+
+/// Borrowed iterator over `(&Value, &mut Value)` entries.
+#[derive(Debug)]
+pub struct IterMut<'a> {
+    pub(super) inner: btree_map::IterMut<'a, Value, Value>,
+}
+
+impl<'a> Iterator for IterMut<'a> {
+    type Item = (&'a Value, &'a mut Value);
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next()
+    }
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+impl<'a> DoubleEndedIterator for IterMut<'a> {
+    #[inline]
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.inner.next_back()
+    }
+}
+
+impl<'a> ExactSizeIterator for IterMut<'a> {
+    #[inline]
+    fn len(&self) -> usize {
+        self.inner.len()
+    }
+}
+
+impl<'a> FusedIterator for IterMut<'a> {}
+
+impl IntoIterator for Object {
+    type Item = (Value, Value);
+    type IntoIter = IntoIter;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        IntoIter {
+            inner: self.inner.into_iter(),
+        }
+    }
+}
+
+impl<'a> IntoIterator for &'a Object {
+    type Item = (&'a Value, &'a Value);
+    type IntoIter = Iter<'a>;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        Iter {
+            inner: self.inner.iter(),
+        }
+    }
+}
+
+impl<'a> IntoIterator for &'a mut Object {
+    type Item = (&'a Value, &'a mut Value);
+    type IntoIter = IterMut<'a>;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        IterMut {
+            inner: self.inner.iter_mut(),
+        }
+    }
+}

src/value/object/mod.rs

@@ -0,0 +1,265 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+//! See [`Object`].
+
+mod iter;
+mod serde;
+
+use alloc::collections::BTreeMap;
+use core::cmp::Ordering;
+use core::fmt;
+use core::ops::Bound;
+
+use crate::value::Value;
+
+pub use iter::{IntoIter, Iter, IterMut};
+
+/// Opaque, ordered key-value map keyed by [`Value`].
+///
+/// The current backing storage is `BTreeMap<Value, Value>`. The inner field
+/// is private so the representation can change (two-tier inline+hash, lazy,
+/// schema-shared) without touching call sites.
+///
+/// # Iteration
+///
+/// - [`Object::iter`] — implementation-defined order; non-resumable.
+/// - [`Object::iter_sorted`] — sorted by `Value::Ord`; non-resumable.
+/// - [`Object::cursor`] / [`Object::next`] — implementation-defined order,
+///   resumable; cheapest per-step cost. Used by interpreter/RVM when iteration
+///   must yield mid-flight.
+#[derive(Default, Clone, Eq, PartialEq)]
+pub struct Object {
+    inner: BTreeMap<Value, Value>,
+}
+
+impl Object {
+    /// Create an empty `Object`.
+    #[inline]
+    pub const fn new() -> Self {
+        Self {
+            inner: BTreeMap::new(),
+        }
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.inner.len()
+    }
+
+    #[inline]
+    pub fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
+
+    #[inline]
+    pub fn get(&self, key: &Value) -> Option<&Value> {
+        self.inner.get(key)
+    }
+
+    #[inline]
+    pub fn contains_key(&self, key: &Value) -> bool {
+        self.inner.contains_key(key)
+    }
+
+    #[inline]
+    pub fn get_mut(&mut self, key: &Value) -> Option<&mut Value> {
+        self.inner.get_mut(key)
+    }
+
+    /// Iteration in implementation-defined order. Non-resumable.
+    ///
+    /// For the current BTree-backed storage this happens to be sorted, but
+    /// callers MUST NOT depend on that. Use [`Object::iter_sorted`] when
+    /// deterministic order is required, or [`Object::cursor`] when iteration
+    /// must yield and resume.
+    #[inline]
+    pub fn iter(&self) -> impl Iterator<Item = (&Value, &Value)> + '_ {
+        self.inner.iter()
+    }
+
+    /// Iteration in sorted key order (by `Value::Ord`). Non-resumable.
+    ///
+    /// Use this for serialization, snapshots, hashing, `Debug`, the
+    /// `object.keys` builtin, etc.
+    #[inline]
+    pub fn iter_sorted(&self) -> Iter<'_> {
+        // BTree backend iterates sorted natively.
+        Iter {
+            inner: self.inner.iter(),
+        }
+    }
+
+    #[inline]
+    pub fn keys(&self) -> impl Iterator<Item = &Value> + '_ {
+        self.inner.keys()
+    }
+
+    /// Keys in sorted order (by `Value::Ord`). Symmetric with
+    /// [`Object::iter_sorted`].
+    #[inline]
+    pub fn keys_sorted(&self) -> impl Iterator<Item = &Value> + '_ {
+        self.iter_sorted().map(|(k, _)| k)
+    }
+
+    #[inline]
+    pub fn values(&self) -> impl Iterator<Item = &Value> + '_ {
+        self.inner.values()
+    }
+
+    #[inline]
+    pub fn iter_mut(&mut self) -> IterMut<'_> {
+        IterMut {
+            inner: self.inner.iter_mut(),
+        }
+    }
+
+    /// Insert a key-value pair. Returns the previous value if any.
+    #[inline]
+    pub fn insert(&mut self, key: Value, value: Value) -> Option<Value> {
+        self.inner.insert(key, value)
+    }
+
+    #[inline]
+    pub fn remove(&mut self, key: &Value) -> Option<Value> {
+        self.inner.remove(key)
+    }
+
+    #[inline]
+    pub fn retain<F>(&mut self, f: F)
+    where
+        F: FnMut(&Value, &mut Value) -> bool,
+    {
+        self.inner.retain(f);
+    }
+
+    #[inline]
+    pub fn clear(&mut self) {
+        self.inner.clear();
+    }
+
+    #[inline]
+    pub fn append(&mut self, other: &mut Object) {
+        self.inner.append(&mut other.inner);
+    }
+
+    /// Gets a mutable reference to the value associated with `key`, inserting
+    /// the result of `default()` if absent. Single O(log n) probe.
+    pub fn get_or_insert_with<F: FnOnce() -> Value>(
+        &mut self,
+        key: Value,
+        default: F,
+    ) -> &mut Value {
+        self.inner.entry(key).or_insert_with(default)
+    }
+
+    /// Wrap into a `Value::Object`.
+    #[inline]
+    pub fn into_value(self) -> Value {
+        Value::Object(crate::Rc::new(self))
+    }
+
+    /// Create a resumable cursor over entries in implementation-defined
+    /// order. Stable for the lifetime of `&self`. O(1).
+    ///
+    /// The cursor is fully self-owned (it stores a clone of the last-seen
+    /// key, not a reference) so it can be stored as a field of a
+    /// long-lived state struct — e.g. an RVM iteration frame that persists
+    /// across instruction dispatches. As a consequence, mutating the
+    /// `Object` between `next()` calls is not rejected by the borrow
+    /// checker; the resulting iteration order in that case is unspecified.
+    #[inline]
+    pub const fn cursor(&self) -> ObjectCursor {
+        ObjectCursor {
+            inner: ObjectCursorInner::BTree(None),
+        }
+    }
+
+    /// Advance `cursor` and yield the next entry. O(log n) for the BTree
+    /// backend (range probe); future hash/inline variants may be O(1).
+    pub fn next<'a>(&'a self, cursor: &mut ObjectCursor) -> Option<(&'a Value, &'a Value)> {
+        let ObjectCursorInner::BTree(ref mut last) = cursor.inner;
+        let next = last.as_ref().map_or_else(
+            || self.inner.iter().next(),
+            |prev| {
+                self.inner
+                    .range((Bound::Excluded(prev.clone()), Bound::Unbounded))
+                    .next()
+            },
+        );
+        let (k, v) = next?;
+        *last = Some(k.clone());
+        Some((k, v))
+    }
+}
+
+/// Opaque resumable cursor over an [`Object`]'s entries in
+/// implementation-defined order.
+///
+/// Self-owned: holds no borrow on the `Object`, so it can be stored as a
+/// field of a long-lived state struct (e.g. an RVM iteration frame).
+#[derive(Debug, Clone)]
+pub struct ObjectCursor {
+    inner: ObjectCursorInner,
+}
+
+#[derive(Debug, Clone)]
+enum ObjectCursorInner {
+    /// BTree backend cursor: tracks last-seen key. `None` means "before start".
+    BTree(Option<Value>),
+}
+
+// ---- Hand-written Ord/PartialOrd ----------------------------------------
+//
+// Implemented in terms of `iter_sorted()` so ordering is consistent with the
+// canonical (sorted) view of the entries and is therefore independent of
+// the storage variant.
+
+impl Ord for Object {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.iter_sorted().cmp(other.iter_sorted())
+    }
+}
+
+impl PartialOrd for Object {
+    #[inline]
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl fmt::Debug for Object {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Use sorted iteration so Debug output is stable across storage
+        // variants.
+        f.debug_map().entries(self.iter_sorted()).finish()
+    }
+}
+
+impl Extend<(Value, Value)> for Object {
+    fn extend<I: IntoIterator<Item = (Value, Value)>>(&mut self, iter: I) {
+        self.inner.extend(iter);
+    }
+}
+
+impl FromIterator<(Value, Value)> for Object {
+    fn from_iter<I: IntoIterator<Item = (Value, Value)>>(iter: I) -> Self {
+        Self {
+            inner: BTreeMap::from_iter(iter),
+        }
+    }
+}
+
+impl From<BTreeMap<Value, Value>> for Object {
+    #[inline]
+    fn from(map: BTreeMap<Value, Value>) -> Self {
+        Self { inner: map }
+    }
+}
+
+impl From<Object> for Value {
+    #[inline]
+    fn from(o: Object) -> Self {
+        o.into_value()
+    }
+}

src/value/object/serde.rs

@@ -0,0 +1,59 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+//! Serde `Serialize`/`Deserialize` impls for [`Object`].
+
+use alloc::string::ToString as _;
+use core::fmt;
+
+use serde::de::{Deserialize, Deserializer, Error as _, MapAccess, Visitor};
+use serde::ser::{Serialize, SerializeMap as _, Serializer};
+
+use super::Object;
+use crate::value::Value;
+
+impl Serialize for Object {
+    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        use serde::ser::Error;
+        let mut map = serializer.serialize_map(Some(self.len()))?;
+        // Sorted iteration: canonical JSON.
+        for (k, v) in self.iter_sorted() {
+            match *k {
+                Value::String(_) => map.serialize_entry(k, v)?,
+                _ => {
+                    // Non-string keys are stringified via serde_json::to_string
+                    // so the resulting JSON has valid string keys.
+                    let key_str = serde_json::to_string(k).map_err(Error::custom)?;
+                    map.serialize_entry(&key_str, v)?;
+                }
+            }
+        }
+        map.end()
+    }
+}
+
+struct ObjectVisitor;
+
+impl<'de> Visitor<'de> for ObjectVisitor {
+    type Value = Object;
+
+    fn expecting(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str("a map of Value to Value")
+    }
+
+    fn visit_map<A: MapAccess<'de>>(self, mut access: A) -> Result<Self::Value, A::Error> {
+        let mut obj = Object::new();
+        while let Some((k, v)) = access.next_entry::<Value, Value>()? {
+            obj.insert(k, v);
+            crate::utils::limits::check_memory_limit_if_needed()
+                .map_err(|err| A::Error::custom(err.to_string()))?;
+        }
+        Ok(obj)
+    }
+}
+
+impl<'de> Deserialize<'de> for Object {
+    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        deserializer.deserialize_map(ObjectVisitor)
+    }
+}

src/value/tests.rs

@@ -0,0 +1,564 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+#![allow(
+    clippy::expect_used,
+    clippy::unwrap_used,
+    clippy::indexing_slicing,
+    clippy::as_conversions,
+    clippy::arithmetic_side_effects,
+    clippy::unseparated_literal_suffix,
+    clippy::map_unwrap_or,
+    clippy::option_if_let_else,
+    clippy::pattern_type_mismatch
+)]
+
+use alloc::collections::BTreeMap;
+use alloc::format;
+use alloc::vec::Vec;
+
+use super::Object;
+use crate::value::Value;
+
+fn val(i: u64) -> Value {
+    Value::from(i)
+}
+
+fn make_pairs(n: u64) -> Vec<(Value, Value)> {
+    (0..n).map(|i| (val(i), val(i.saturating_mul(2)))).collect()
+}
+
+const SIZES: &[u64] = &[0, 1, 2, 4, 8, 64, 256, 1024];
+
+/// `iter_sorted` must yield entries in the same order as a `BTreeMap` oracle.
+#[test]
+fn object_iter_sorted_matches_btreemap_oracle() {
+    for &n in SIZES {
+        let pairs = make_pairs(n);
+        let oracle: BTreeMap<Value, Value> = pairs.iter().cloned().collect();
+        let obj: Object = pairs.into_iter().collect();
+        let actual: Vec<(&Value, &Value)> = obj.iter_sorted().collect();
+        let expected: Vec<(&Value, &Value)> = oracle.iter().collect();
+        assert_eq!(actual, expected, "size {n}");
+    }
+}
+
+/// `iter` may be in any order, but as a multiset must equal the oracle's entries.
+#[test]
+fn object_iter_multiset_equality_with_oracle() {
+    for &n in SIZES {
+        let pairs = make_pairs(n);
+        let oracle: BTreeMap<Value, Value> = pairs.iter().cloned().collect();
+        let obj: Object = pairs.into_iter().collect();
+        assert_eq!(obj.len(), oracle.len(), "size {n}");
+        let mut a: Vec<(Value, Value)> = obj.iter().map(|(k, v)| (k.clone(), v.clone())).collect();
+        let mut b: Vec<(Value, Value)> =
+            oracle.iter().map(|(k, v)| (k.clone(), v.clone())).collect();
+        a.sort();
+        b.sort();
+        assert_eq!(a, b);
+    }
+}
+
+/// Serialize-then-deserialize must round-trip through JSON without loss.
+#[test]
+fn object_serde_roundtrip() {
+    for &n in &[0_u64, 1, 8, 64] {
+        let pairs: Vec<(Value, Value)> = (0..n)
+            .map(|i| (Value::String(format!("k{i}").into()), val(i)))
+            .collect();
+        let obj: Object = pairs.into_iter().collect();
+        let json = serde_json::to_string(&obj).expect("ser");
+        let back: Object = serde_json::from_str(&json).expect("de");
+        assert_eq!(obj, back, "size {n}");
+    }
+}
+
+/// Equality depends only on contents, not the order keys were inserted.
+#[test]
+fn object_eq_invariant_to_insertion_order() {
+    let mut a = Object::new();
+    let mut b = Object::new();
+    for i in 0..32_u64 {
+        a.insert(val(i), val(i.saturating_add(1)));
+    }
+    for i in (0..32_u64).rev() {
+        b.insert(val(i), val(i.saturating_add(1)));
+    }
+    assert_eq!(a, b);
+}
+
+/// `remove` returns the prior value (or `None`) and `retain` keeps only matching entries.
+#[test]
+fn object_remove_and_retain() {
+    let mut obj: Object = make_pairs(16).into_iter().collect();
+    assert_eq!(obj.remove(&val(0)), Some(val(0)));
+    assert!(obj.remove(&val(100)).is_none());
+    obj.retain(|_, v| {
+        if let Value::Number(ref n) = *v {
+            n.as_u64().is_some_and(|x| x % 4 == 0)
+        } else {
+            false
+        }
+    });
+    for (_, v) in obj.iter_sorted() {
+        if let Value::Number(ref n) = *v {
+            assert_eq!(n.as_u64().expect("u64") % 4, 0);
+        }
+    }
+}
+
+/// `IntoIterator` for `Object` (by value) yields every entry exactly once.
+#[test]
+fn object_into_iterator_owned() {
+    let obj: Object = make_pairs(8).into_iter().collect();
+    let collected: Vec<(Value, Value)> = obj.into_iter().collect();
+    assert_eq!(collected.len(), 8);
+}
+
+// ---- Duplicate-key semantics --------------------------------------------
+
+/// `FromIterator` keeps the last value when the same key appears multiple times.
+#[test]
+fn object_from_iter_last_wins_on_duplicate_keys() {
+    let obj = Object::from_iter([(val(0), val(1)), (val(0), val(2))]);
+    assert_eq!(obj.get(&val(0)), Some(&val(2)));
+    assert_eq!(obj.len(), 1);
+}
+
+/// `From<BTreeMap>` adopts `BTreeMap`'s own last-write-wins semantics for duplicates.
+#[test]
+fn object_from_btreemap_last_wins_on_duplicate_keys() {
+    let mut bm: BTreeMap<Value, Value> = BTreeMap::new();
+    bm.insert(val(0), val(1));
+    bm.insert(val(0), val(2));
+    let obj: Object = bm.into();
+    assert_eq!(obj.get(&val(0)), Some(&val(2)));
+    assert_eq!(obj.len(), 1);
+}
+
+// ---- get_or_insert_with --------------------------------------------------
+
+/// `get_or_insert_with` inserts the default when the key is absent and returns a mutable ref to it.
+#[test]
+fn object_get_or_insert_with_inserts_when_absent() {
+    let mut obj = Object::new();
+    let v = obj.get_or_insert_with(val(7), || val(42));
+    assert_eq!(*v, val(42));
+    *v = val(43);
+    assert_eq!(obj.get(&val(7)), Some(&val(43)));
+}
+
+/// `get_or_insert_with` returns the existing value and never invokes the default closure.
+#[test]
+fn object_get_or_insert_with_returns_existing_when_present() {
+    let mut obj = Object::new();
+    obj.insert(val(7), val(1));
+    let mut closure_called = false;
+    let v = obj.get_or_insert_with(val(7), || {
+        closure_called = true;
+        val(999)
+    });
+    assert_eq!(*v, val(1));
+    assert!(!closure_called, "default closure must not run when present");
+}
+
+// ---- Accessor coverage ---------------------------------------------------
+
+/// Smoke-test every accessor: `contains_key`/`get`/`get_mut`/`keys`/`values`/`iter`/`iter_mut`/`append`/`clear`.
+#[test]
+fn object_accessor_coverage() {
+    let mut obj: Object = make_pairs(4).into_iter().collect();
+
+    assert!(obj.contains_key(&val(0)));
+    assert!(!obj.contains_key(&val(100)));
+
+    assert_eq!(obj.get(&val(2)), Some(&val(4)));
+
+    if let Some(v) = obj.get_mut(&val(1)) {
+        *v = val(999);
+    }
+    assert_eq!(obj.get(&val(1)), Some(&val(999)));
+
+    let keys: Vec<&Value> = obj.keys().collect();
+    assert_eq!(keys.len(), 4);
+    let values: Vec<&Value> = obj.values().collect();
+    assert_eq!(values.len(), 4);
+
+    for (_, v) in obj.iter_mut() {
+        *v = val(0);
+    }
+    for (_, v) in obj.iter() {
+        assert_eq!(*v, val(0));
+    }
+
+    let mut other = Object::new();
+    other.insert(val(100), val(200));
+    obj.append(&mut other);
+    assert!(other.is_empty());
+    assert!(obj.contains_key(&val(100)));
+
+    obj.clear();
+    assert!(obj.is_empty());
+}
+
+// ---- IntoIterator for references -----------------------------------------
+
+/// `IntoIterator` for `&Object` yields shared refs to every entry.
+#[test]
+fn object_into_iterator_ref() {
+    let obj: Object = make_pairs(4).into_iter().collect();
+    let mut count = 0;
+    for (_k, _v) in &obj {
+        count += 1;
+    }
+    assert_eq!(count, 4);
+}
+
+/// `IntoIterator` for `&mut Object` exposes mutable refs to values; mutations persist.
+#[test]
+fn object_into_iterator_ref_mut() {
+    let mut obj: Object = make_pairs(4).into_iter().collect();
+    for (_k, v) in &mut obj {
+        *v = val(0);
+    }
+    for (_, v) in obj.iter() {
+        assert_eq!(*v, val(0));
+    }
+}
+
+// ---- Cursor tests --------------------------------------------------------
+
+/// Driving `cursor`+`next` to completion visits each entry exactly once.
+#[test]
+fn object_cursor_yields_every_entry_once() {
+    for &n in SIZES {
+        let pairs = make_pairs(n);
+        let obj: Object = pairs.clone().into_iter().collect();
+        let mut cursor = obj.cursor();
+        let mut collected: Vec<(Value, Value)> = Vec::new();
+        while let Some((k, v)) = obj.next(&mut cursor) {
+            collected.push((k.clone(), v.clone()));
+        }
+        let mut a = collected;
+        a.sort();
+        let mut b = pairs;
+        b.sort();
+        assert_eq!(a, b, "size {n}");
+    }
+}
+
+/// A freshly-constructed cursor restarts from the beginning, independent of any prior cursor's state.
+#[test]
+fn object_cursor_resumable_fresh_cursor_restarts() {
+    let obj: Object = make_pairs(8).into_iter().collect();
+    let mut c1 = obj.cursor();
+    let _ = obj.next(&mut c1);
+    let _ = obj.next(&mut c1);
+    let mut c2 = obj.cursor();
+    let first_again = obj.next(&mut c2);
+    let first_original = obj.iter().next();
+    assert_eq!(
+        first_again.map(|(k, v)| (k.clone(), v.clone())),
+        first_original.map(|(k, v)| (k.clone(), v.clone()))
+    );
+}
+
+/// When `Object` is shared via `Rc`, `Rc::make_mut` clones — leaving an in-flight cursor on the original snapshot unaffected.
+#[test]
+fn object_cursor_snapshot_independence_via_rc() {
+    use crate::Rc;
+    let mut obj = Object::new();
+    obj.insert(Value::from("a"), Value::from(1));
+    obj.insert(Value::from("b"), Value::from(2));
+    obj.insert(Value::from("c"), Value::from(3));
+    let rc_obj = Rc::new(obj);
+
+    let alias = Rc::clone(&rc_obj);
+    let mut cursor = rc_obj.cursor();
+    let _ = rc_obj.next(&mut cursor);
+
+    let mut alias_for_mut = alias;
+    Rc::make_mut(&mut alias_for_mut).insert(Value::from("d"), Value::from(4));
+    Rc::make_mut(&mut alias_for_mut).remove(&Value::from("a"));
+
+    assert_eq!(rc_obj.len(), 3);
+    let mut remaining = 0;
+    while rc_obj.next(&mut cursor).is_some() {
+        remaining += 1;
+    }
+    assert_eq!(remaining, 2);
+}
+
+/// A cursor over an empty `Object` returns `None` on the first call.
+#[test]
+fn object_cursor_empty_returns_none_immediately() {
+    let obj = Object::new();
+    let mut cursor = obj.cursor();
+    assert!(obj.next(&mut cursor).is_none());
+}
+
+/// Mutating an `Object` between `next()` calls is well-defined: the cursor
+/// must not panic and must terminate. The visit order, and whether
+/// inserted/removed keys appear, is intentionally unspecified — this test
+/// only pins the safety + termination guarantees that callers (e.g. a
+/// future RVM iteration frame) may rely on. It must NOT assert any
+/// particular order or count, or future backend swaps will be forced to
+/// honor an accidental contract.
+#[test]
+fn object_cursor_mutation_between_steps_is_safe_and_terminates() {
+    let mut obj: Object = make_pairs(16).into_iter().collect();
+    let mut cursor = obj.cursor();
+
+    // Yield a few entries before mutating.
+    for _ in 0..3 {
+        let _ = obj.next(&mut cursor);
+    }
+
+    // Interleave mutations and steps. Each yielded entry must, at the
+    // moment of yield, be a real entry in the map.
+    obj.insert(val(100), val(100));
+    if let Some((k, v)) = obj.next(&mut cursor) {
+        assert_eq!(obj.get(k), Some(v));
+    }
+    obj.remove(&val(2));
+    if let Some((k, v)) = obj.next(&mut cursor) {
+        assert_eq!(obj.get(k), Some(v));
+    }
+    obj.clear();
+    // After clear(), draining the cursor must terminate (not panic, not
+    // loop) within a bounded number of calls.
+    let mut terminated = false;
+    for _ in 0..32 {
+        if obj.next(&mut cursor).is_none() {
+            terminated = true;
+            break;
+        }
+    }
+    assert!(terminated, "cursor failed to terminate after clear()");
+}
+
+// ---- Hand-written Ord consistency ---------------------------------------
+
+/// `Ord` (built atop `iter_sorted`) is invariant to insertion order.
+#[test]
+fn object_ord_invariant_to_insertion_order() {
+    let mut a = Object::new();
+    let mut b = Object::new();
+    for i in 0..16_u64 {
+        a.insert(val(i), val(i.saturating_add(1)));
+    }
+    for i in (0..16_u64).rev() {
+        b.insert(val(i), val(i.saturating_add(1)));
+    }
+    use core::cmp::Ordering;
+    assert_eq!(a.cmp(&b), Ordering::Equal);
+}
+
+/// `Ord` agrees with lexicographic comparison of the sorted-entries view.
+#[test]
+fn object_ord_lexicographic_on_sorted_entries() {
+    let a: Object = [(val(0), val(0)), (val(1), val(1))].into_iter().collect();
+    let b: Object = [(val(0), val(0)), (val(2), val(2))].into_iter().collect();
+    assert!(a < b);
+}
+
+/// `empty < non_empty` and a shorter prefix compares less than its extension.
+#[test]
+fn object_ord_empty_and_prefix() {
+    use core::cmp::Ordering;
+    let empty = Object::new();
+    let one: Object = [(val(0), val(0))].into_iter().collect();
+    let two: Object = [(val(0), val(0)), (val(1), val(1))].into_iter().collect();
+    assert_eq!(empty.cmp(&one), Ordering::Less);
+    assert_eq!(one.cmp(&two), Ordering::Less);
+    assert_eq!(two.cmp(&empty), Ordering::Greater);
+}
+
+/// When keys match, `Ord` falls through to comparing values.
+#[test]
+fn object_ord_breaks_ties_on_values() {
+    use core::cmp::Ordering;
+    let a: Object = [(val(0), val(1))].into_iter().collect();
+    let b: Object = [(val(0), val(2))].into_iter().collect();
+    assert_eq!(a.cmp(&b), Ordering::Less);
+}
+
+/// `PartialOrd` must agree with `Ord` for every input pair.
+#[test]
+fn object_partial_cmp_matches_cmp() {
+    let a: Object = [(val(0), val(0)), (val(1), val(1))].into_iter().collect();
+    let b: Object = [(val(0), val(0)), (val(2), val(2))].into_iter().collect();
+    assert_eq!(a.partial_cmp(&b), Some(a.cmp(&b)));
+    assert_eq!(b.partial_cmp(&a), Some(b.cmp(&a)));
+    assert_eq!(a.partial_cmp(&a), Some(core::cmp::Ordering::Equal));
+}
+
+// ---- Debug / keys_sorted determinism ------------------------------------
+
+/// `Debug` output is byte-identical for equal Objects regardless of insertion order.
+#[test]
+fn object_debug_invariant_to_insertion_order() {
+    let mut a = Object::new();
+    let mut b = Object::new();
+    for i in 0..8_u64 {
+        a.insert(val(i), val(i));
+    }
+    for i in (0..8_u64).rev() {
+        b.insert(val(i), val(i));
+    }
+    assert_eq!(format!("{a:?}"), format!("{b:?}"));
+}
+
+/// `keys_sorted` yields exactly `iter_sorted().map(|(k,_)| k)`.
+#[test]
+fn object_keys_sorted_matches_iter_sorted_keys() {
+    let obj: Object = make_pairs(16).into_iter().collect();
+    let from_keys: Vec<&Value> = obj.keys_sorted().collect();
+    let from_iter: Vec<&Value> = obj.iter_sorted().map(|(k, _)| k).collect();
+    assert_eq!(from_keys, from_iter);
+}
+
+// ---- Serde: non-string keys & determinism --------------------------------
+
+/// `Serialize` stringifies non-string keys, and equal Objects produce identical JSON
+/// regardless of insertion order.
+#[test]
+fn object_serialize_non_string_keys_and_deterministic() {
+    let pairs = [
+        (Value::from("alpha"), val(1)),
+        (Value::Bool(true), val(2)),
+        (val(7), val(3)),
+    ];
+    let a: Object = pairs.iter().cloned().collect();
+    let mut b = Object::new();
+    for (k, v) in pairs.iter().rev().cloned() {
+        b.insert(k, v);
+    }
+    let ja = serde_json::to_string(&a).expect("ser a");
+    let jb = serde_json::to_string(&b).expect("ser b");
+    assert_eq!(ja, jb, "serialization must be deterministic");
+
+    // Non-string keys appear as quoted strings in the resulting JSON.
+    let v: serde_json::Value = serde_json::from_str(&ja).expect("parse");
+    let obj = v.as_object().expect("json object");
+    assert!(
+        obj.contains_key("true"),
+        "bool key was not stringified: {ja}"
+    );
+    assert!(
+        obj.contains_key("7"),
+        "number key was not stringified: {ja}"
+    );
+    assert!(obj.contains_key("alpha"));
+}
+
+// ---- Extend / append duplicate-key semantics -----------------------------
+
+/// `extend` overwrites existing entries (last-write-wins) and preserves length when
+/// only existing keys are touched.
+#[test]
+fn object_extend_last_wins_and_empty_noop() {
+    let mut obj: Object = [(val(0), val(0)), (val(1), val(1))].into_iter().collect();
+    obj.extend([(val(0), val(99))]);
+    assert_eq!(obj.get(&val(0)), Some(&val(99)));
+    assert_eq!(obj.len(), 2);
+
+    let before = obj.len();
+    obj.extend(core::iter::empty::<(Value, Value)>());
+    assert_eq!(obj.len(), before, "empty extend is a no-op");
+}
+
+/// `append` drains `other` into `self`, overwriting on overlapping keys.
+#[test]
+fn object_append_overlapping_keys_drain_and_overwrite() {
+    let mut a: Object = [(val(0), val(0)), (val(1), val(1))].into_iter().collect();
+    let mut b: Object = [(val(1), val(99)), (val(2), val(2))].into_iter().collect();
+    a.append(&mut b);
+    assert!(b.is_empty(), "append must drain `other`");
+    assert_eq!(a.len(), 3);
+    assert_eq!(a.get(&val(1)), Some(&val(99)));
+    assert_eq!(a.get(&val(2)), Some(&val(2)));
+}
+
+// ---- Iterator trait surface ---------------------------------------------
+
+/// `DoubleEndedIterator`/`ExactSizeIterator`/`FusedIterator` and `size_hint` all
+/// behave correctly across partial consumption from both ends.
+#[test]
+fn object_iter_sorted_double_ended_and_exact_size() {
+    let obj: Object = make_pairs(4).into_iter().collect();
+    let mut it = obj.iter_sorted();
+    assert_eq!(it.len(), 4);
+    assert_eq!(it.size_hint(), (4, Some(4)));
+
+    let first = it.next().expect("front");
+    let last = it.next_back().expect("back");
+    assert_eq!(it.len(), 2);
+    assert_eq!(it.size_hint(), (2, Some(2)));
+    assert_ne!(first.0, last.0, "front and back must differ for n=4");
+
+    // Drain remaining.
+    while it.next().is_some() {}
+    assert_eq!(it.len(), 0);
+    // FusedIterator: stays None after exhaustion.
+    assert!(it.next().is_none());
+    assert!(it.next().is_none());
+    assert!(it.next_back().is_none());
+}
+
+/// `IntoIter` also honors `DoubleEndedIterator` and `ExactSizeIterator`.
+#[test]
+fn object_into_iter_double_ended_and_exact_size() {
+    let obj: Object = make_pairs(4).into_iter().collect();
+    let mut it = obj.into_iter();
+    assert_eq!(it.len(), 4);
+    let _ = it.next().expect("front");
+    let _ = it.next_back().expect("back");
+    assert_eq!(it.len(), 2);
+    let collected: Vec<_> = it.collect();
+    assert_eq!(collected.len(), 2);
+}
+
+/// `IterMut` decrements its `len()` after consuming from the front.
+#[test]
+fn object_iter_mut_exact_size() {
+    let mut obj: Object = make_pairs(3).into_iter().collect();
+    let mut it = obj.iter_mut();
+    assert_eq!(it.len(), 3);
+    let _ = it.next().expect("front");
+    assert_eq!(it.len(), 2);
+}
+
+/// `Iter` is `Clone`; the clone iterates independently from the same point.
+#[test]
+fn object_iter_sorted_clone_is_independent() {
+    let obj: Object = make_pairs(4).into_iter().collect();
+    let mut a = obj.iter_sorted();
+    let _ = a.next();
+    let b = a.clone();
+    let rest_a: Vec<_> = a.collect();
+    let rest_b: Vec<_> = b.collect();
+    assert_eq!(rest_a, rest_b);
+}
+
+// ---- default / insert ---------------------------------------------------
+
+/// `Object::default()` and `Object::new()` produce equal, empty Objects.
+#[test]
+fn object_default_equals_new_and_is_empty() {
+    let a = Object::default();
+    let b = Object::new();
+    assert_eq!(a, b);
+    assert!(a.is_empty());
+    assert_eq!(a.len(), 0);
+}
+
+/// `insert` returns `None` for a fresh key and `Some(old)` when overwriting.
+#[test]
+fn object_insert_returns_previous_value() {
+    let mut obj = Object::new();
+    assert_eq!(obj.insert(val(0), val(1)), None);
+    assert_eq!(obj.insert(val(0), val(2)), Some(val(1)));
+    assert_eq!(obj.get(&val(0)), Some(&val(2)));
+}

tests/azure_policy/mod.rs

@@ -544,16 +544,14 @@ fn make_context(case: &TestCase) -> Result<Value> {
         let map = ctx.as_object_mut()?;
         // Only inject if the caller didn't already provide requestContext
         // in the context object, to avoid clobbering custom test setups.
-        map.entry(Value::from("requestContext")).or_insert(rc_val);
+        map.get_or_insert_with(Value::from("requestContext"), || rc_val);
     } else if let Some(ref api_ver) = case.api_version {
         let map = ctx.as_object_mut()?;
-        if let std::collections::btree_map::Entry::Vacant(e) =
-            map.entry(Value::from("requestContext"))
-        {
+        if !map.contains_key(&Value::from("requestContext")) {
             let mut req_ctx = Value::new_object();
             let rc_map = req_ctx.as_object_mut()?;
             rc_map.insert(Value::from("apiVersion"), Value::from(api_ver.clone()));
-            e.insert(req_ctx);
+            map.insert(Value::from("requestContext"), req_ctx);
         }
     }
 

tests/opa.rs

@@ -380,7 +380,11 @@ fn run_opa_tests(opa_tests_dir: String, folders: &[String]) -> Result<()> {
         }
         let path = Path::new(&path_str);
         let path_dir = path.strip_prefix(tests_path)?.parent().unwrap();
-        let path_dir_str = path_dir.to_string_lossy().to_string();
+        // Normalize to forward slashes so the folder filter at the
+        // `folders.iter().any(|f| &path_dir_str == f)` check below matches
+        // CLI arguments like `v0/aggregates` on Windows, where
+        // `to_string_lossy` yields backslash separators by default.
+        let path_dir_str = path_dir.to_string_lossy().replace('\\', "/");
         let folder_name = folder_name_from_path(path_dir);
         let skip_rvm_for_folder = folder_name
             .as_deref()

tests/rvm/vm/suites/loops/set_comprehensions.yaml

@@ -137,3 +137,45 @@ cases:
       - "Return { value: 7 }"               # Return result set
     want_result:
       set!: [1, null, 2]
+
+  # Set iteration resumes from `Bound::Excluded(current_item)`, so the
+  # ComprehensionAdd path must snapshot the current value into
+  # `IterationState::Set.current_item` before advancing — otherwise
+  # iteration stops after the first element. This case exercises
+  # Set-source comprehension end-to-end to lock that requirement in.
+  - note: set_source_visits_all_elements
+    description: Comprehension over a Set source must yield every element, not just the first
+    example_rego: |
+      src := {1, 2, 3, 4}
+      {x | x := src[_]}  # {1, 2, 3, 4}
+    literals:
+      - 1
+      - 2
+      - 3
+      - 4
+    instruction_params:
+      comprehension_start_params:
+        - mode: "Set"
+          collection_reg: 0
+          key_reg: 4
+          value_reg: 5
+          result_reg: 7
+          body_start: 11
+          comprehension_end: 13
+    instructions:
+      - "SetNew { dest: 0 }"                # Build source set {1,2,3,4} in register 0
+      - "Load { dest: 1, literal_idx: 0 }"
+      - "SetAdd { set: 0, value: 1 }"
+      - "Load { dest: 2, literal_idx: 1 }"
+      - "SetAdd { set: 0, value: 2 }"
+      - "Load { dest: 3, literal_idx: 2 }"
+      - "SetAdd { set: 0, value: 3 }"
+      - "Load { dest: 6, literal_idx: 3 }"
+      - "SetAdd { set: 0, value: 6 }"
+      - "SetNew { dest: 7 }"                # Initialize result set
+      - "ComprehensionStart { params_index: 0 }"   # Iterate over Set source
+      - "ComprehensionAdd { value_reg: 5 }" # Add current value to result
+      - "Halt"
+      - "Return { value: 7 }"
+    want_result:
+      set!: [1, 2, 3, 4]