Use Github actions

.github/workflows/ci.yml

@@ -0,0 +1,33 @@
+name: CI
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        include:
+          - elixir: 1.12.3
+            otp: 24.0
+          - elixir: 1.12.3
+            otp: 23.3
+          - elixir: 1.12.3
+            otp: 22.3
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Elixir
+      uses: erlef/setup-elixir@885971a72ed1f9240973bd92ab57af8c1aa68f24
+      with:
+        elixir-version: ${{ matrix.elixir }}
+        otp-version: ${{ matrix.otp }}
+    - name: Restore dependencies cache
+      uses: actions/cache@v2
+      with:
+        path: deps
+        key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
+        restore-keys: ${{ runner.os }}-mix-
+    - name: Install dependencies
+      run: mix deps.get
+    - name: Run tests
+      env:
+        MIX_ENV: ${{ matrix.env }}
+      run: mix test

README.md

@@ -1,6 +1,6 @@
 # OPQ: One Pooled Queue
 
-[![Travis](https://img.shields.io/travis/fredwu/opq.svg)](https://travis-ci.org/fredwu/opq)
+[![Build Status](https://github.com/fredwu/opq/actions/workflows/ci.yml/badge.svg)](https://github.com/fredwu/opq/actions)
 [![Code Climate](https://img.shields.io/codeclimate/github/fredwu/opq.svg)](https://codeclimate.com/github/fredwu/opq)
 [![CodeBeat](https://codebeat.co/badges/76916047-5b66-466d-91d3-7131a269899a)](https://codebeat.co/projects/github-com-fredwu-opq-master)
 [![Coverage](https://img.shields.io/coveralls/fredwu/opq.svg)](https://coveralls.io/github/fredwu/opq?branch=master) [![Hex.pm](https://img.shields.io/hexpm/v/opq.svg)](https://hex.pm/packages/opq)