add github workflow

.github/workflows/build.yml

@@ -0,0 +1,43 @@
+name: build
+
+on: [push, pull_request]
+
+jobs:
+  linux:
+    strategy:
+      matrix:
+        target: [linux-arm64, linux-armhf, linux-i686, linux-riscv64, linux-x86_64]
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - uses: distrho/dpf-makefile-action@v1
+        with:
+          target: ${{ matrix.target }}
+
+  macos:
+    strategy:
+      matrix:
+        target: [macos-intel, macos-universal]
+    runs-on: macos-13
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - uses: distrho/dpf-makefile-action@v1
+        with:
+          target: ${{ matrix.target }}
+
+  windows:
+    strategy:
+      matrix:
+        target: [win32, win64]
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - uses: distrho/dpf-makefile-action@v1
+        with:
+          target: ${{ matrix.target }}