diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index a6cc8dc..84accfe 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,82 +1,160 @@
-name: CI
-on:
-  push:
-    branches:
-      - master
-  pull_request:
-  workflow_dispatch:
+@@ -1,155 +1,28 @@
+name: Tests
+
+on: [pull_request, push]
+
+
+
 
-concurrency:
-  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
-  cancel-in-progress: true
 
 jobs:
-  build:
-    timeout-minutes: 90
+  tests:
+    env:
+      NPROC: 2
     strategy:
       fail-fast: false
       matrix:
-        target:
-          - os: linux
-            cpu: amd64
-          - os: linux
-            cpu: i386
-          - os: macos
-            cpu: amd64
-          - os: windows
-            cpu: amd64
-          #- os: windows
-            #cpu: i386
-        branch: [version-1-6]
-        include:
-          - target:
-              os: linux
-            builder: ubuntu-20.04
-            shell: bash
-          - target:
-              os: macos
-            builder: macos-12
-            shell: bash
-          - target:
-              os: windows
-            builder: windows-2019
-            shell: msys2 {0}
-
+        cache_nonce: [ 1 ]
+        nim_version: [ 1.6.6 ]
+        platform:
+          - {
+            icon: 🐧,
+            label: Linux,
+            os: ubuntu,
+            shell: bash --noprofile --norc -eo pipefail
+          }
+          - {
+            icon: 🍎,
+            label: macOS,
+            os: macos,
+            shell: bash --noprofile --norc -eo pipefail
+          }
+          - {
+            icon: 🏁,
+            label: Windows,
+            os: windows,
+            shell: msys2
+          }
+    name: ${{ matrix.platform.icon }} ${{ matrix.platform.label }} - Nim v${{ matrix.nim_version }}
+    runs-on: ${{ matrix.platform.os }}-latest
     defaults:
       run:
-        shell: ${{ matrix.shell }}
+        shell: ${{ matrix.platform.shell }} {0}
 
-    name: '${{ matrix.target.os }}-${{ matrix.target.cpu }} (Nim ${{ matrix.branch }})'
-    runs-on: ${{ matrix.builder }}
-    continue-on-error: ${{ matrix.branch == 'devel' }}
     steps:
-      - name: Checkout
+      # - name: Install tools and libraries via APT (Linux)
+      #   if: matrix.platform.os == 'ubuntu'
+      #   run: |
+      #     sudo apt update
+      #     sudo apt install -y \
+      #       ...
+
+      - name: Install tools and libraries via Homebrew (macOS)
+        if: matrix.platform.os == 'macos'
+        run: |
+          brew update
+          brew install \
+            findutils \
+            libomp \
+            llvm@14
+
+      - name: Install tools and libraries via MSYS2 (Windows)
+        if: matrix.platform.os == 'windows'
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: UCRT64
+          install: >
+            base-devel
+            git
+            mingw-w64-ucrt-x86_64-cmake
+            mingw-w64-ucrt-x86_64-toolchain
+
+      - name: Checkout sources from GitHub
         uses: actions/checkout@v2
         with:
           submodules: true
 
-      - name: Setup Nim
-        uses: "./.github/actions/install_nim"
-        with:
-          os: ${{ matrix.target.os }}
-          cpu: ${{ matrix.target.cpu }}
-          shell: ${{ matrix.shell }}
-          nim_branch: ${{ matrix.branch }}
-
-      - name: Restore deps from cache
-        id: deps-cache
-        uses: actions/cache@v3
-        with:
-          path: nimbledeps
-          key: nimbledeps-${{ hashFiles('.pinned') }}
-
-      - name: Install deps
-        if: ${{ steps.deps-cache.outputs.cache-hit != 'true' }}
+      - name: Calculate cache member paths
+        id: calc-paths
         run: |
+          if [[ ${{ matrix.platform.os }} = windows ]]; then
+            echo "::set-output name=bash_env::$(cygpath -m "${HOME}")/.bash_env"
+            echo "::set-output name=choosenim::$(cygpath -m "${USERPROFILE}")/.choosenim"
+            echo "::set-output name=nimble::$(cygpath -m "${HOME}")/.nimble"
+          else
+            echo "::set-output name=bash_env::${HOME}/.bash_env"
+            echo "::set-output name=choosenim::${HOME}/.choosenim"
+            echo "::set-output name=nimble::${HOME}/.nimble"
+          fi
+
+      - name: Restore choosenim and Nim tooling from cache
+        id: choosenim-nim-tooling-cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ${{ steps.calc-paths.outputs.bash_env }}
+            ${{ steps.calc-paths.outputs.choosenim }}
+            ${{ steps.calc-paths.outputs.nimble }}/bin
+          key: ${{ matrix.platform.os }}-nim_version:${{ matrix.nim_version }}-cache_nonce:${{ matrix.cache_nonce }}
+
+      - name: Install choosenim and Nim tooling
+        if: steps.choosenim-nim-tooling-cache.outputs.cache-hit != 'true'
+        run: |
+          mkdir -p "${HOME}/Downloads"
+          cd "${HOME}/Downloads"
+          curl https://nim-lang.org/choosenim/init.sh -sSf -O
+          chmod +x init.sh
+          if [[ ${{ matrix.platform.os }} = windows ]]; then
+            mkdir -p "$(cygpath "${USERPROFILE}")/.nimble/bin"
+          fi
+          CHOOSENIM_CHOOSE_VERSION=${{ matrix.nim_version }} ./init.sh -y
+          if [[ ${{ matrix.platform.os }} = windows ]]; then
+            mv "$(cygpath "${USERPROFILE}")/.nimble" "${HOME}/"
+            # intention is to rely only on libs provided by the OS and MSYS2 env
+            rm -rf "${HOME}/.nimble/bin/"*.dll
+            rm -rf "${HOME}/.nimble/bin/"*.pem
+          fi
+          echo 'export NIMBLE_DIR="${HOME}/.nimble"' >> "${HOME}/.bash_env"
+          echo 'export PATH="${NIMBLE_DIR}/bin:${PATH}"' >> "${HOME}/.bash_env"
+
+      - name: Install project dependencies
+        run: |
+          source "${HOME}/.bash_env"
+          cd "${NIMBLE_DIR}/bin"
+          # delete broken symlinks, which can arise because e.g. the cache
+          # restored a symlink that points to an executable within
+          # ../pkgs/foo-1.2.3/ but the project's .nimble file has been updated
+          # to install foo-#head; in the case of a broken symlink, nimble's
+          # auto-overwrite fails
+          if [[ ${{ matrix.platform.os }} = macos ]]; then
+            gfind . -xtype l -delete
+          else
+            find . -xtype l -delete
+          fi
+          cd -
           nimble --accept install
 
-      - name: Run tests
+      - name: Build and run tests
         run: |
-          nim --version
-          nimble --version
-          nimble test
\ No newline at end of file
+          source "${HOME}/.bash_env"
+          if [[ ${{ matrix.platform.os }} = windows ]]; then
+            touch tests/testleopard.exe
+          else
+            touch tests/testleopard
+          fi
+          if [[ ${{ matrix.platform.os }} = macos ]]; then
+            export PATH="$(brew --prefix llvm@14)/bin:${PATH}"
+            export LDFLAGS="-L$(brew --prefix libomp)/lib -L$(brew --prefix llvm@14)/lib -Wl,-rpath,$(brew --prefix llvm@14)/lib"
+            compiler_extra_options="-d:LeopardCmakeFlags='-DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=$(brew --prefix llvm@14)/bin/clang -DCMAKE_CXX_COMPILER=$(brew --prefix llvm@14)/bin/clang++' -d:LeopardExtraCompilerlags='-fopenmp' -d:LeopardExtraLinkerFlags='-fopenmp -L$(brew --prefix libomp)/lib'"
+          fi
+          eval nimble --verbose test -d:release --mm:refc ${compiler_extra_options}
+          eval nimble --verbose test -d:release --mm:orc ${compiler_extra_options}
+          if [[ ${{ matrix.platform.os }} = macos ]]; then
+            echo
+            echo otool -L tests/testleopard
+            otool -L tests/testleopard
+          else
+            echo
+            echo ldd tests/testleopard
+            ldd tests/testleopard
+          fi