diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4fbbed6..9c4ccb8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,8 +15,8 @@ jobs:
       - name: Run Norminette
         run: make norm
   build:
-    name: build
-    runs-on: ubuntu-latest
+    name: build + check allowed functions
+    runs-on: macos-12
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
@@ -28,6 +28,10 @@ jobs:
         run: make fclean
       - name: Build checker
         run: make bonus
+      - name: Build push_swap
+        run: make
+      - name: check allowed_functions
+        run: test/check_allowed_functions.sh
   unit_test:
     name: unit_test
     runs-on: macos-12
diff --git a/test/check_allowed_functions.sh b/test/check_allowed_functions.sh
new file mode 100755
index 0000000..1bf2bac
--- /dev/null
+++ b/test/check_allowed_functions.sh
@@ -0,0 +1,26 @@
+#!/bin/bash
+
+check_binary_symbols() {
+    local binary="$1"
+    if [ ! -f $binary ]; then
+        echo "Error: Binary file '$binary' not found."
+        exit 1
+    fi
+    local undefined_symbols=$(nm -u "$binary" | sed 's/^_*//')
+    for symbol in $undefined_symbols; do
+        if [[ ! " ${allowed_functions[@]} " =~ " ${symbol}" ]]; then
+            echo "Error: $binary: Disallowed function used: ${symbol}"
+            exit 1
+        fi
+    done
+}
+
+allowed_functions=("read" "write" "malloc" "free" "exit" "error" "dyld_stub_binder")
+
+# Check symbols for push_swap
+check_binary_symbols "push_swap"
+
+# Check symbols for checker
+check_binary_symbols "checker"
+
+echo "All used functions are allowed."