diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8274ede16..bff0d5bf4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -27,6 +27,8 @@ env:
   VAMPIRREPO: anoma/vamp-ir
   VAMPIRVERSION: v0.1.3
   CAIRO_VM_VERSION: ae06ba04f3b6864546b6baeeebf1b0735ddccb5d
+  JUST_ARGS: enableOptimized=yes runtimeCcArg=$CC runtimeLibtoolArg=$LIBTOOL
+  STACK_BUILD_ARGS: --pedantic -j4 --ghc-options=-j
 
 jobs:
   pre-commit:
@@ -58,6 +60,8 @@ jobs:
   build-and-test-linux:
     runs-on: ubuntu-22.04
     steps:
+      - uses: extractions/setup-just@v2
+
       - name: Checkout our repository
         uses: actions/checkout@v3
         with:
@@ -158,7 +162,7 @@ jobs:
       - name: Make runtime
         run: |
           cd main
-          make runtime
+          just ${{ env.JUST_ARGS }} build runtime
 
       # We use the options:
       #   - -fhide-source-paths
@@ -176,9 +180,10 @@ jobs:
 
       - name: Stack setup
         id: stack
-        uses: freckle/stack-action@v4
+        uses: freckle/stack-action@v5
         with:
           working-directory: main
+          stack-build-arguments: ${{ env.STACK_BUILD_ARGS }}
           test: false
 
       - name: Install and test Juvix
@@ -186,8 +191,8 @@ jobs:
         if: ${{ success() }}
         run: |
           cd main
-          make install
-          make test
+          just ${{ env.JUST_ARGS }} install
+          just ${{ env.JUST_ARGS }} test
 
       - name: Typecheck and format Juvix examples
         if: ${{ success() }}
@@ -225,6 +230,8 @@ jobs:
   build-and-test-macos:
     runs-on: macos-12
     steps:
+      - uses: extractions/setup-just@v2
+
       - name: Checkout our repository
         uses: actions/checkout@v3
         with:
@@ -354,7 +361,7 @@ jobs:
       - name: Make runtime
         run: |
           cd main
-          make CC=$CC LIBTOOL=$LIBTOOL runtime
+          just ${{ env.JUST_ARGS }} build runtime
 
       # We use the options:
       #   - -fhide-source-paths
@@ -372,9 +379,10 @@ jobs:
 
       - name: Stack setup
         id: stack
-        uses: freckle/stack-action@v4
+        uses: freckle/stack-action@v5
         with:
           working-directory: main
+          stack-build-arguments: ${{ env.STACK_BUILD_ARGS }}
           test: false
 
       - name: Add homebrew clang to the PATH (macOS)
@@ -399,8 +407,8 @@ jobs:
         if: ${{ success() }}
         run: |
           cd main
-          make CC=$CC LIBTOOL=$LIBTOOL install
-          make CC=$CC LIBTOOL=$LIBTOOL test
+          just ${{ env.JUST_ARGS }} install
+          just ${{ env.JUST_ARGS }} test
 
       - name: Typecheck and format Juvix examples
         if: ${{ success() }}
diff --git a/justfile b/justfile
index a1fb6eca9..9a030d32c 100644
--- a/justfile
+++ b/justfile
@@ -22,6 +22,17 @@ stack := "stack"
 # the command used to run ormolu
 ormolu := "ormolu"
 
+# The CC argument to the runtime Makefile
+runtimeCcArg := ''
+
+# The LIBTOOL argument to the runtime Makefile
+runtimeLibtoolArg := ''
+
+# The flags used in the runtime make commands
+runtimeCcFlag := if runtimeCcArg == '' { '' } else { "CC=" + runtimeCcArg }
+runtimeLibtoolFlag := if runtimeLibtoolArg == '' { '' } else { "LIBTOOL=" + runtimeLibtoolArg }
+runtimeArgs := trim(runtimeCcFlag + ' ' + runtimeLibtoolFlag)
+
 # flags used in the stack command
 stackOptFlag := if enableOptimized == '' { '--fast' } else { '' }
 # The ghc `-j` flag defaults to number of cpus when no argument is passed
@@ -93,7 +104,7 @@ run-profile +cmd:
 
 # Build the juvix runtime
 _buildRuntime:
-    cd runtime && make -j 4 -s
+    cd runtime && make {{ runtimeArgs }} -j 4 -s
 
 # Build the project. `build runtime` builds only the runtime.
 [no-exit-message]
@@ -104,10 +115,10 @@ build *opts:
 
     case $opts in
         runtime)
-            just _buildRuntime
+            just runtimeArgs="{{ runtimeArgs }}" _buildRuntime
             ;;
         *)
-            just _buildRuntime
+            just runtimeArgs="{{ runtimeArgs }}" _buildRuntime
             set -x
             {{ stack }} build {{ stackArgs }}
             ;;