.github: add workflow files

.github/workflows/ci.yml

@@ -0,0 +1,35 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - otp: "27.1"
+            rebar3: 3.24.0
+            os: ubuntu-latest
+
+          - otp: "26.2.5"
+            rebar3: 3.24.0
+            os: ubuntu-latest
+
+    steps:
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: ${{ matrix.otp }}
+          rebar3-version: ${{ matrix.rebar3 }}
+
+      - name: Compile
+        run: rebar3 compile
+
+      - name: Run unit tests
+        run: rebar3 eunit

.github/workflows/publish.yml

@@ -0,0 +1,24 @@
+name: Publish to Hex
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out
+        uses: actions/checkout@v3
+
+      - name: Setup rebar3 hex
+        run: |
+          mkdir -p ~/.config/rebar3/
+          echo "{plugins, [rebar3_hex]}." >> ~/.config/rebar3/rebar.config
+
+      - name: Publish to Hex.pm
+        env:
+          HEX_API_KEY: ${{ secrets.HEX_API_KEY }}
+        run: |
+          rebar3 hex publish --repo hexpm --yes