diff --git a/.appveyor.yml b/.appveyor.yml
index 16198f6a7..8650ef08e 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -18,15 +18,17 @@ before_build:
   #- choco install codecov
 
 build_script:
-  - bash.exe -lc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe fmt"
-  - bash.exe -lc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe vet"
-  - bash.exe -lc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe build"
-  - bash.exe -lc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe binaries"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe setup"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe fmt"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe vet"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:/c/gopath/bin:$PATH ; mingw32-make.exe ineffassign"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe build"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:$PATH ; mingw32-make.exe binaries"
 
 test_script:
   # TODO: need an equivalent of TRAVIS_COMMIT_RANGE
   # - GIT_CHECK_EXCLUDE="./vendor" TRAVIS_COMMIT_RANGE="${TRAVIS_COMMIT_RANGE/.../..}" C:\MinGW\bin\mingw32-make.exe dco
-  - bash.exe -lc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe integration"
+  - bash.exe -elc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe integration"
   # TODO: re-enable once the content unit-test have been updated to pass on windows
   #- bash.exe -lc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe coverage"
   #- bash.exe -lc "export PATH=/c/tools/mingw64/bin:/c/gopath/src/github.com/containerd/containerd/bin:$PATH ; mingw32-make.exe root-coverage"
diff --git a/.travis.yml b/.travis.yml
index 7df354b88..e118aa959 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -28,7 +28,6 @@ addons:
       - libprotobuf-dev
 
 env:
-  - TRAVIS_GOOS=windows TRAVIS_CGO_ENABLED=1
   - TRAVIS_GOOS=linux TRAVIS_CGO_ENABLED=1
   - TRAVIS_GOOS=darwin TRAVIS_CGO_ENABLED=0
 
@@ -36,7 +35,6 @@ before_install:
   - uname -r
 
 install:
-  - if [ "$TRAVIS_GOOS" = "windows" ] ; then sudo apt-get install -y gcc-multilib gcc-mingw-w64; export CC=x86_64-w64-mingw32-gcc ; export CXX=x86_64-w64-mingw32-g++ ; fi
   - wget https://github.com/google/protobuf/releases/download/v3.1.0/protoc-3.1.0-linux-x86_64.zip -O /tmp/protoc-3.1.0-linux-x86_64.zip
   - unzip -o -d /tmp/protobuf /tmp/protoc-3.1.0-linux-x86_64.zip
   - export PATH=$PATH:/tmp/protobuf/bin/
@@ -55,7 +53,9 @@ script:
 # FIXME: For non-linux GOOS, without running `go build -i`, vet fails with `vet: import failed: can't find import: fmt`...
 # Note that `go build -i` requires write permission to GOROOT. (So it is not called in Makefile)
   - go build -i .
+  - make setup
   - make vet
+  - make ineffassign
   - make build
   - make binaries
   - if [ "$GOOS" = "linux" ]; then sudo make install ; fi
diff --git a/cmd/ctr/utils.go b/cmd/ctr/utils.go
index 70270c4ea..7e827b49f 100644
--- a/cmd/ctr/utils.go
+++ b/cmd/ctr/utils.go
@@ -87,7 +87,7 @@ func appContext(clicontext *cli.Context) (gocontext.Context, gocontext.CancelFun
 		ctx       = gocontext.Background()
 		timeout   = clicontext.GlobalDuration("timeout")
 		namespace = clicontext.GlobalString("namespace")
-		cancel    = func() {}
+		cancel    gocontext.CancelFunc
 	)
 
 	ctx = namespaces.WithNamespace(ctx, namespace)
diff --git a/container_test.go b/container_test.go
index 3cde907c5..f621cdae9 100644
--- a/container_test.go
+++ b/container_test.go
@@ -69,7 +69,7 @@ func TestNewContainer(t *testing.T) {
 	if container.ID() != id {
 		t.Errorf("expected container id %q but received %q", id, container.ID())
 	}
-	if spec, err = container.Spec(); err != nil {
+	if _, err = container.Spec(); err != nil {
 		t.Error(err)
 		return
 	}
diff --git a/progress/bar.go b/progress/bar.go
index fa916efcb..ced8862ef 100644
--- a/progress/bar.go
+++ b/progress/bar.go
@@ -58,7 +58,7 @@ func (h Bar) Format(state fmt.State, r rune) {
 	n += copy(p[n:], []byte(reset))
 
 	if negative > 0 {
-		n += copy(p[n:len(p)-1], bytes.Repeat([]byte("-"), negative))
+		copy(p[n:len(p)-1], bytes.Repeat([]byte("-"), negative))
 	}
 
 	state.Write(p)
diff --git a/remotes/docker/schema1/converter.go b/remotes/docker/schema1/converter.go
index 4459ce94f..7d24d156f 100644
--- a/remotes/docker/schema1/converter.go
+++ b/remotes/docker/schema1/converter.go
@@ -217,6 +217,9 @@ func (c *Converter) fetchBlob(ctx context.Context, desc ocispec.Descriptor) erro
 		defer r.Close()
 
 		gr, err := gzip.NewReader(r)
+		if err != nil {
+			return err
+		}
 		defer gr.Close()
 
 		_, err = io.Copy(calc, gr)
@@ -237,6 +240,9 @@ func (c *Converter) fetchBlob(ctx context.Context, desc ocispec.Descriptor) erro
 
 		eg.Go(func() error {
 			gr, err := gzip.NewReader(pr)
+			if err != nil {
+				return err
+			}
 			defer gr.Close()
 
 			_, err = io.Copy(calc, gr)
diff --git a/snapshot/overlay/overlay_test.go b/snapshot/overlay/overlay_test.go
index 1bd9d923d..5b47f07ae 100644
--- a/snapshot/overlay/overlay_test.go
+++ b/snapshot/overlay/overlay_test.go
@@ -110,8 +110,7 @@ func TestOverlayOverlayMount(t *testing.T) {
 		return
 	}
 	key := "/tmp/test"
-	mounts, err := o.Prepare(ctx, key, "")
-	if err != nil {
+	if _, err = o.Prepare(ctx, key, ""); err != nil {
 		t.Error(err)
 		return
 	}
@@ -119,6 +118,7 @@ func TestOverlayOverlayMount(t *testing.T) {
 		t.Error(err)
 		return
 	}
+	var mounts []mount.Mount
 	if mounts, err = o.Prepare(ctx, "/tmp/layer2", "base"); err != nil {
 		t.Error(err)
 		return