diff --git a/.github/workflows/make.yml b/.github/workflows/make.yml
index 55268a0..c87caa0 100644
--- a/.github/workflows/make.yml
+++ b/.github/workflows/make.yml
@@ -13,5 +13,16 @@ jobs:
     - uses: actions/checkout@v2
       with:
         submodules: true
+
+    - name: brew
+      if: matrix.os == 'macos-latest'
+      shell: bash
+      run: brew install re2c
+
+    - name: apt-get
+      if: matrix.os == 'ubuntu-latest'
+      shell: bash
+      run: sudo apt-get -y install re2c
+
     - name: make
       run: make all