diff --git a/.clang-format b/.clang-format
new file mode 100644
index 00000000..0b68049a
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,7 @@
+BreakBeforeBraces: Allman
+ColumnLimit: 0
+IndentCaseLabels: true
+IndentWidth: 8
+TabWidth: 8
+UseTab: Always
+SortIncludes: false
diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
new file mode 100644
index 00000000..55cef96a
--- /dev/null
+++ b/.github/workflows/format.yml
@@ -0,0 +1,16 @@
+name: Format sourcecode
+on: [push, pull_request]
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install dependencies
+        run: |
+          curl https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+          sudo add-apt-repository -y 'deb http://apt.llvm.org/bionic/ llvm-toolchain-bionic-9 main'
+          sudo apt install clang-format-9
+      - name: Format code
+        run: |
+          find src/ -type f -name '*.c' -name '*.c' | xargs clang-format-9 -i
+          git diff-index --quiet HEAD -- || (git diff && exit 1)
diff --git a/src/thirdparty/.clang-format b/src/thirdparty/.clang-format
new file mode 100644
index 00000000..9d159247
--- /dev/null
+++ b/src/thirdparty/.clang-format
@@ -0,0 +1,2 @@
+DisableFormat: true
+SortIncludes: false