diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b59cdb386..6426f4bd3 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -18,6 +18,11 @@ env:
   CCACHE_DIR: ${{ github.workspace }}/.ccache
   CCACHE_LIMIT_MULTIPLE: 0.95
 
+defaults:
+  run:
+    shell: bash
+    working-directory: repo
+
 jobs:
 
 
@@ -27,9 +32,8 @@ jobs:
     outputs:
       matrix: ${{ steps.generate.outputs.matrix }}
     steps:
-    - uses: actions/checkout@v2
     - id: generate
-      name: Run 'generate_matrix.sh'
+      working-directory: ${{ github.workspace }}
       run: |
         if [ '${{ github.event_name }}' = 'pull_request' ]; then
           matrix='[ "ubuntu-20.04" ]'
@@ -45,27 +49,25 @@ jobs:
       fail-fast: false
       matrix:
         os: ${{ fromJson(needs.Matrix.outputs.matrix) }}
-        target:
-          - { name: opt, ccache_size: 48M  }
-          - { name: dbg, ccache_size: 208M }
         compiler:
           - { cc: clang, cxx: clang++ }
           - { cc: gcc,   cxx: g++     }
     runs-on: ${{ matrix.os }}
-    name: Build | ${{ matrix.os }} | ${{ matrix.compiler.cc }} | ${{ matrix.target.name }}
+    name: Build | ${{ matrix.os }} | ${{ matrix.compiler.cc }}
     env:
       CI_BUILD_STAGE_NAME: build
       CI_RUNS_ON: ${{ matrix.os }}
-      CI_MAKE_SRC_TARGET: ${{ matrix.target.name }}
       CC: ${{ matrix.compiler.cc }}
       CXX: ${{ matrix.compiler.cxx }}
-      CACHE_BASE_KEY: build-${{ matrix.os }}-${{ matrix.compiler.cc }}-${{ matrix.target.name }}
-      CCACHE_MAXSIZE: ${{ matrix.target.ccache_size }} # Per build matrix entry (1G in total)
-      VERILATOR_ARCHIVE: verilator-${{ github.sha }}-${{ matrix.os }}-${{ matrix.compiler.cc }}-${{ matrix.target.name }}.tar.gz
+      CACHE_BASE_KEY: build-${{ matrix.os }}-${{ matrix.compiler.cc }}
+      CCACHE_MAXSIZE: 250M # Per build matrix entry (1500M in total)
+      VERILATOR_ARCHIVE: verilator-${{ github.sha }}-${{ matrix.os }}-${{ matrix.compiler.cc }}.tar.gz
     steps:
 
     - name: Checkout
       uses: actions/checkout@v2
+      with:
+        path: repo
 
     - name: Cache $CCACHE_DIR
       uses: actions/cache@v2
@@ -81,17 +83,17 @@ jobs:
       run: ./ci/ci-install.bash
 
     - name: Build
-      run: |
-        ccache -z
-        ./ci/ci-script.bash
-        ccache -s
-        tar cvzf ${{ env.VERILATOR_ARCHIVE }} bin
+      run: ./ci/ci-script.bash
 
-    - name: Upload Verilator artifact
+    - name: Tar up repository
+      working-directory: ${{ github.workspace }}
+      run: tar --posix -c -z -f ${{ env.VERILATOR_ARCHIVE }} repo
+
+    - name: Upload tar archive
       uses: actions/upload-artifact@v2
       with:
+        path: ${{ github.workspace }}/${{ env.VERILATOR_ARCHIVE }}
         name: ${{ env.VERILATOR_ARCHIVE }}
-        path: ${{ env.VERILATOR_ARCHIVE }}
 
 
   Test:
@@ -118,11 +120,18 @@ jobs:
       CXX: ${{ matrix.compiler.cxx }}
       CACHE_BASE_KEY: test-${{ matrix.os }}-${{ matrix.compiler.cc }}-${{ matrix.suite }}
       CCACHE_MAXSIZE: 64M # Per build matrix entry (1920M in total)
-      VERILATOR_ARCHIVE_BASE: verilator-${{ github.sha }}-${{ matrix.os }}-${{ matrix.compiler.cc }}
+      VERILATOR_ARCHIVE: verilator-${{ github.sha }}-${{ matrix.os }}-${{ matrix.compiler.cc }}.tar.gz
     steps:
 
-    - name: Checkout
-      uses: actions/checkout@v2
+    - name: Download tar archive
+      uses: actions/download-artifact@v2
+      with:
+        name: ${{ env.VERILATOR_ARCHIVE }}
+        path: ${{ github.workspace }}
+
+    - name: Unpack tar archive
+      working-directory: ${{ github.workspace }}
+      run: tar -x -z -f ${{ env.VERILATOR_ARCHIVE }}
 
     - name: Cache $CCACHE_DIR
       uses: actions/cache@v2
@@ -134,29 +143,10 @@ jobs:
         restore-keys: |
           ${{ env.CACHE_KEY }}-
 
-    - name: Download Verilator artifact (opt)
-      uses: actions/download-artifact@v2
-      with:
-        name: ${{ env.VERILATOR_ARCHIVE_BASE }}-opt.tar.gz
-
-    - name: Download Verilator artifact (dbg)
-      uses: actions/download-artifact@v2
-      with:
-        name: ${{ env.VERILATOR_ARCHIVE_BASE }}-dbg.tar.gz
-
-    - name: Unpack Verilator artifacts
-      run: |
-        tar xvzf ${{ env.VERILATOR_ARCHIVE_BASE }}-opt.tar.gz
-        tar xvzf ${{ env.VERILATOR_ARCHIVE_BASE }}-dbg.tar.gz
-
     - name: Install test dependencies
-      run: |
-        ./ci/ci-install.bash
+      run: ./ci/ci-install.bash
 
     - name: Test
       env:
         TESTS: ${{ matrix.suite }}
-      run: |
-        ccache -z
-        ./ci/ci-script.bash
-        ccache -s
+      run: ./ci/ci-script.bash
diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index fdbe90e85..9fc5e94f2 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -14,6 +14,11 @@ env:
   COVERAGE: 1
   VERILATOR_ARCHIVE: verilator-coverage-${{ github.sha }}.tar.gz
 
+defaults:
+  run:
+    shell: bash
+    working-directory: repo
+
 jobs:
 
 
@@ -26,22 +31,24 @@ jobs:
 
     - name: Checkout
       uses: actions/checkout@v2
+      with:
+        path: repo
 
     - name: Install packages for build
-      env:
-        CI_BUILD_STAGE_NAME: build
       run: ./ci/ci-install.bash
 
     - name: Build
-      run: |
-        ./ci/ci-script.bash
-        tar cvzf ${{ env.VERILATOR_ARCHIVE }} bin src/obj*/*.o src/obj*/*.gcno
+      run: ./ci/ci-script.bash
 
-    - name: Upload Verilator artifact
+    - name: Tar up repository
+      working-directory: ${{ github.workspace }}
+      run: tar --posix -c -z -f ${{ env.VERILATOR_ARCHIVE }} repo
+
+    - name: Upload tar archive
       uses: actions/upload-artifact@v2
       with:
+        path: ${{ github.workspace }}/${{ env.VERILATOR_ARCHIVE }}
         name: ${{ env.VERILATOR_ARCHIVE }}
-        path: ${{ env.VERILATOR_ARCHIVE }}
 
 
   Test:
@@ -72,25 +79,20 @@ jobs:
       CI_RUNS_ON: ubuntu-20.04
     steps:
 
-    - name: Checkout
-      uses: actions/checkout@v2
-
-    - name: Download Verilator artifact
+    - name: Download tar archive
       uses: actions/download-artifact@v2
       with:
         name: ${{ env.VERILATOR_ARCHIVE }}
+        path: ${{ github.workspace }}
 
-    - name: Unapack Verilator artifact
-      run: |
-        tar xvzf ${{ env.VERILATOR_ARCHIVE }}
-        touch src/obj*/*.o src/obj*/*.gcno
+    - name: Unpack tar archive
+      working-directory: ${{ github.workspace }}
+      run: tar -x -z -f ${{ env.VERILATOR_ARCHIVE }}
 
     - name: Install test dependencies
-      run: |
-        ./ci/ci-install.bash
+      run: ./ci/ci-install.bash
 
     - name: Test
       env:
         TESTS: coverage-${{ matrix.test }}${{ matrix.num }}
-      run: |
-        ./ci/ci-script.bash
+      run: ./ci/ci-script.bash
diff --git a/Makefile.in b/Makefile.in
index d6b9fd70e..07e3731ef 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -230,7 +230,7 @@ all_nomsg: verilator_exe $(VL_INST_MAN_FILES)
 verilator_exe verilator_bin$(EXEEXT) verilator_bin_dbg$(EXEEXT) verilator_coverage_bin_dbg$(EXEEXT):
 	@echo ------------------------------------------------------------
 	@echo "making verilator in src"
-	$(MAKE) -C src $(OBJCACHE_JOBS) $(CI_MAKE_SRC_TARGET)
+	$(MAKE) -C src $(OBJCACHE_JOBS)
 
 .PHONY:msg_test
 msg_test: all_nomsg
diff --git a/ci/ci-install.bash b/ci/ci-install.bash
index ff0719f4e..6b4e517ff 100755
--- a/ci/ci-install.bash
+++ b/ci/ci-install.bash
@@ -101,9 +101,6 @@ elif [ "$CI_BUILD_STAGE_NAME" = "test" ]; then
   fi
   yes yes | sudo cpan -M $CI_CPAN_REPO -fi Parallel::Forker
   install-vcddiff
-
-  autoconf
-  ./configure --enable-longtests --enable-ccwarn
 else
   ##############################################################################
   # Unknown build stage
diff --git a/ci/ci-script.bash b/ci/ci-script.bash
index 70ded6d2c..6ff282a78 100755
--- a/ci/ci-script.bash
+++ b/ci/ci-script.bash
@@ -41,7 +41,9 @@ if [ "$CI_BUILD_STAGE_NAME" = "build" ]; then
   if [ "$COVERAGE" != 1 ]; then
     autoconf
     ./configure --enable-longtests --enable-ccwarn
+    ccache -z
     "$MAKE" -j "$NPROC" -k
+    ccache -s
     if [ "$CI_OS_NAME" = "osx" ]; then
       file bin/verilator_bin
       file bin/verilator_bin_dbg
@@ -83,6 +85,7 @@ elif [ "$CI_BUILD_STAGE_NAME" = "test" ]; then
   [ "$CI_RUNS_ON" = 'ubuntu-20.04' ] && sanitize='--sanitize' || sanitize=''
 
   # Run the specified test
+  ccache -z
   case $TESTS in
     dist-vlt-0)
       "$MAKE" -C test_regress SCENARIOS="--dist --vlt $sanitize" DRIVER_HASHSET=--hashset=0/3
@@ -169,6 +172,8 @@ elif [ "$CI_BUILD_STAGE_NAME" = "test" ]; then
       fatal "Unknown test: $TESTS"
       ;;
   esac
+  ccache -s
+
   # Upload coverage data
   if [[ $TESTS == coverage-* ]]; then
     bash <(cat ci/coverage-upload.sh) -f nodist/obj_dir/coverage/app_total.info