diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f9ade0e8c..d5b6f38fd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,12 +3,10 @@ on:
   push:
     branches:
       - main
-      - master
       - 'release/**'
   pull_request:
     branches:
       - main
-      - master
       - 'release/**'
 
 jobs:
@@ -27,19 +25,9 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
-        with:
-          path: src/github.com/containerd/containerd
-
-      - name: Set env
-        shell: bash
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
-
       - uses: golangci/golangci-lint-action@v2
         with:
           version: v1.36.0
-          working-directory: src/github.com/containerd/containerd
           args: --timeout=5m
 
   #
@@ -55,11 +43,6 @@ jobs:
         with:
           go-version: '1.16.6'
 
-      - shell: bash
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
-
       - uses: actions/checkout@v2
         with:
           path: src/github.com/containerd/containerd
@@ -124,21 +107,9 @@ jobs:
       - uses: actions/setup-go@v2
         with:
           go-version: '1.16.6'
-
-      - name: Set env
-        shell: bash
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
-
       - uses: actions/checkout@v2
-        with:
-          path: src/github.com/containerd/containerd
-
-      - run: GO111MODULE=on go get github.com/cpuguy83/go-md2man/v2@v2.0.1
-
+      - run: go get github.com/cpuguy83/go-md2man/v2@v2.0.1
       - run: make man
-        working-directory: src/github.com/containerd/containerd
 
   # Make sure binaries compile with other platforms
   crossbuild:
@@ -170,14 +141,7 @@ jobs:
       - uses: actions/setup-go@v2
         with:
           go-version: '1.16.6'
-      - name: Set env
-        shell: bash
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
       - uses: actions/checkout@v2
-        with:
-          path: src/github.com/containerd/containerd
       - run: |
           set -e -x
 
@@ -211,9 +175,8 @@ jobs:
           if [ -n "${packages}" ]; then
             sudo apt-get update && sudo apt-get install -y ${packages}
           fi
-        name: install deps
+        name: Install deps
       - name: Build
-        working-directory: src/github.com/containerd/containerd
         env:
           GOOS: ${{matrix.goos}}
           GOARCH: ${{matrix.goarch}}
@@ -360,24 +323,17 @@ jobs:
           go-version: '1.16.6'
 
       - uses: actions/checkout@v2
-        with:
-          path: src/github.com/containerd/containerd
-
-      - name: Set env
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
 
       - name: Install containerd dependencies
         env:
           RUNC_FLAVOR: ${{ matrix.runc }}
+          GOFLAGS: -modcacherw
         run: |
           sudo apt-get install -y gperf
           sudo -E PATH=$PATH script/setup/install-seccomp
           sudo -E PATH=$PATH script/setup/install-runc
-          sudo -E PATH=$PATH script/setup/install-cni
+          sudo -E PATH=$PATH script/setup/install-cni $(grep containernetworking/plugins go.mod | awk '{print $2}')
           sudo -E PATH=$PATH script/setup/install-critools
-        working-directory: src/github.com/containerd/containerd
 
       - name: Install criu
         run: |
@@ -389,12 +345,10 @@ jobs:
         env:
           CGO_ENABLED: 1
         run: |
-          make binaries
+          make binaries GO_BUILD_FLAGS="-mod=vendor"
           sudo -E PATH=$PATH make install
-        working-directory: src/github.com/containerd/containerd
 
       - run: sudo -E PATH=$PATH script/setup/install-gotestsum
-        working-directory: src/github.com/containerd/containerd
       - name: Tests
         env:
           GOPROXY: direct
@@ -402,7 +356,6 @@ jobs:
         run: |
           make test
           sudo -E PATH=$PATH make root-test
-        working-directory: src/github.com/containerd/containerd
 
       - name: Integration 1
         env:
@@ -416,7 +369,6 @@ jobs:
                   extraflags="EXTRA_TESTFLAGS=-no-criu";
           }
           sudo -E PATH=$PATH make integration ${extraflags} TESTFLAGS_RACE=-race
-        working-directory: src/github.com/containerd/containerd
 
       # Run the integration suite a second time. See discussion in github.com/containerd/containerd/pull/1759
       - name: Integration 2
@@ -431,14 +383,12 @@ jobs:
                   extraflags="EXTRA_TESTFLAGS=-no-criu";
           }
           sudo -E PATH=$PATH TESTFLAGS_PARALLEL=1 make integration ${extraflags}
-        working-directory: src/github.com/containerd/containerd
 
       - name: CRI Integration Test
         env:
           TEST_RUNTIME: ${{ matrix.runtime }}
         run: |
           CONTAINERD_RUNTIME=$TEST_RUNTIME make cri-integration
-        working-directory: src/github.com/containerd/containerd
 
       - name: cri-tools critest
         env:
@@ -490,25 +440,13 @@ jobs:
       - uses: actions/setup-go@v2
         with:
           go-version: '1.16.6'
-
       - uses: actions/checkout@v2
-        with:
-          path: src/github.com/containerd/containerd
-
-      - name: Set env
-        run: |
-          echo "GOPATH=${{ github.workspace }}" >> $GITHUB_ENV
-          echo "${{ github.workspace }}/bin" >> $GITHUB_PATH
-
       - run: sudo -E PATH=$PATH script/setup/install-gotestsum
-        working-directory: src/github.com/containerd/containerd
       - name: Tests
         env:
           GOPROXY: direct
           GOTESTSUM_JUNITFILE: "${{ github.workspace }}/macos-test-junit.xml"
-        run: |
-          make test
-        working-directory: src/github.com/containerd/containerd
+        run: make test
       - uses: actions/upload-artifact@v2
         if: always()
         with:
diff --git a/Makefile b/Makefile
index 20141d458..1807cfdec 100644
--- a/Makefile
+++ b/Makefile
@@ -252,11 +252,11 @@ genman: man/containerd.8 man/ctr.8
 
 man/containerd.8: FORCE
 	@echo "$(WHALE) $@"
-	$(GO) run ${GO_TAGS} cmd/gen-manpages/main.go $(@F) $(@D)
+	$(GO) run -mod=readonly ${GO_TAGS} cmd/gen-manpages/main.go $(@F) $(@D)
 
 man/ctr.8: FORCE
 	@echo "$(WHALE) $@"
-	$(GO) run ${GO_TAGS} cmd/gen-manpages/main.go $(@F) $(@D)
+	$(GO) run -mod=readonly ${GO_TAGS} cmd/gen-manpages/main.go $(@F) $(@D)
 
 man/%: docs/man/%.md FORCE
 	@echo "$(WHALE) $@"
diff --git a/script/setup/install-cni b/script/setup/install-cni
index b70c31764..9545d5601 100755
--- a/script/setup/install-cni
+++ b/script/setup/install-cni
@@ -21,7 +21,7 @@
 #
 set -eu -o pipefail
 
-CNI_COMMIT=$(grep containernetworking/plugins "$GOPATH"/src/github.com/containerd/containerd/go.mod | awk '{print $2}')
+CNI_COMMIT=${1:-$(grep containernetworking/plugins "$GOPATH"/src/github.com/containerd/containerd/go.mod | awk '{print $2}')}
 CNI_DIR=${DESTDIR:=''}/opt/cni
 CNI_CONFIG_DIR=${DESTDIR}/etc/cni/net.d
 
diff --git a/script/setup/install-critools b/script/setup/install-critools
index 126ac7b9b..4dff1f65c 100755
--- a/script/setup/install-critools
+++ b/script/setup/install-critools
@@ -22,7 +22,7 @@ set -eu -o pipefail
 
 script_dir="$(cd -- "$(dirname -- "$0")" > /dev/null 2>&1; pwd -P)"
 
-cd "$GOPATH"
+cd "$(go env GOPATH)"
 go get -u github.com/onsi/ginkgo/ginkgo
 
 : "${CRITEST_COMMIT:=$(cat "${script_dir}/critools-version")}"