diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b9f644c..7693595 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -92,7 +92,7 @@ jobs:
           path: |
             ~/.nimble
             ${{ github.workspace }}/.nimble
-          key: ${{ matrix.target.os }}-${{ matrix.target.cpu }}-dotnimble-${{ hashFiles('nimble.lock') }}
+          key: ${{ matrix.builder }}-${{ matrix.target.cpu }}-dotnimble-${{ hashFiles('nimble.lock') }}
 
       - name: Setup Nimble
         uses: "./.github/actions/install_nimble"
diff --git a/.github/workflows/codecov.yml b/.github/workflows/codecov.yml
new file mode 100644
index 0000000..63a900d
--- /dev/null
+++ b/.github/workflows/codecov.yml
@@ -0,0 +1,69 @@
+name: Generate and upload code coverage
+
+on:
+  #On push to common branches, this computes the "bases stats" for PRs
+  push:
+    branches:
+      - main
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  All_Tests:
+    name: All tests
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        nim-options: [
+          ""
+        ]
+        test-program: [
+          "test"
+        ]
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Environment setup
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y lcov build-essential git curl
+          mkdir coverage
+
+      - name: Restore nimble dependencies from cache
+        id: nimble_deps
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/.nimble
+          key: ubuntu-20.04-amd64-${{ hashFiles('nimble.lock') }}
+
+      - name: Setup Nimble
+        uses: "./.github/actions/install_nimble"
+        with:
+          os: linux
+          cpu: x64
+
+      - name: Setup Env
+        run: |
+          nimble -v
+
+      - name: Setup Deps
+        run: |
+          nimble install -d
+          nimble setup
+
+      - name: Run tests
+        run: |
+          nimble -y --verbose coverage
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v2
+        with:
+          directory: ./coverage/
+          fail_ci_if_error: true
+          files: ./coverage/coverage.f.info
+          flags: unittests
+          name: codecov-umbrella
+          verbose: true
diff --git a/build.nims b/build.nims
index 164c795..b4c5d7f 100644
--- a/build.nims
+++ b/build.nims
@@ -42,11 +42,11 @@ task coverage, "generates code coverage report":
 
   var nimSrcs = ""
   for f in walkDirRec(".", {pcFile}):
-    if f.endswith(".nim"): nimSrcs.add " " & f.quoteShell()
+    if f.endswith(".nim"): nimSrcs.add " " & f.absolutePath.quoteShell()
 
   echo "======== Running Tests ======== "
   exec("nim c -r tests/coverage.nim")
-  # exec("rm nimcache/*.c")
+  exec("rm nimcache/*.c")
   rmDir("coverage"); mkDir("coverage")
   echo " ======== Running LCOV ======== "
   exec("lcov --capture --directory nimcache --output-file coverage/coverage.info")
@@ -54,5 +54,6 @@ task coverage, "generates code coverage report":
   echo " ======== Generating HTML coverage report ======== "
   exec("genhtml coverage/coverage.f.info --output-directory coverage/report ")
   echo " ======== Opening HTML coverage report in browser... ======== "
-  exec("open coverage/report/index.html")
+  if findExe("open") != "":
+    exec("open coverage/report/index.html")