diff --git a/tests/all.js b/tests/all.js
index 5a20b83..4b1faaf 100644
--- a/tests/all.js
+++ b/tests/all.js
@@ -3,4 +3,5 @@
 describe('serverless-webpack', () => {
   require('./validate.test');
   require('./compile.test');
+  require('./run.test');
 });
diff --git a/tests/compile.test.js b/tests/compile.test.js
new file mode 100644
index 0000000..4d668df
--- /dev/null
+++ b/tests/compile.test.js
@@ -0,0 +1,79 @@
+'use strict';
+
+const chai = require('chai');
+const sinon = require('sinon');
+const mockery = require('mockery');
+const Serverless = require('serverless');
+const makeWebpackMock = require('./webpack.mock');
+chai.use(require('sinon-chai'));
+const expect = chai.expect;
+
+describe('compile', () => {
+  let webpackMock;
+  let baseModule;
+  let module;
+  let serverless;
+
+  before(() => {
+    mockery.enable({ warnOnUnregistered: false });
+    webpackMock = makeWebpackMock();
+    mockery.registerMock('webpack', webpackMock);
+    baseModule = require('../lib/compile');
+  });
+
+  after(() => {
+    mockery.disable();
+    mockery.deregisterAll();
+  });
+
+  beforeEach(() => {
+    serverless = new Serverless();
+    serverless.cli = { log: sinon.spy() };
+    webpackMock._resetSpies();
+    module = Object.assign({
+      serverless,
+      options: {},
+    }, baseModule);
+  });
+
+  it('should expose a `compile` method', () => {
+    expect(module.compile).to.be.a('function');
+  });
+
+  it('should compile with webpack from a context configuration', () => {
+    const testWebpackConfig = 'testconfig';
+    module.webpackConfig = testWebpackConfig;
+    return module
+      .compile()
+      .then(() => {
+        expect(webpackMock).to.have.been.calledWith(testWebpackConfig);
+        expect(webpackMock.compilerMock.run).to.have.callCount(1);
+      });
+  });
+
+  it('should fail if there are compilation errors', () => {
+    module.webpackConfig = 'testconfig';
+    webpackMock.statsMock.compilation.errors = ['error'];
+    return module
+      .compile()
+      .catch((err) => {
+        expect(err.toString()).to.match(/compilation error/);
+      });
+  });
+
+  it('should set context `webpackOutputPath`, `originalServicePath`, `serverless.config.servicePath`', () => {
+    const testWebpackConfig = 'testconfig';
+    module.webpackConfig = testWebpackConfig;
+    const testServicePath = 'testServicePath';
+    module.serverless.config.servicePath = testServicePath;
+    const testOutputPath = 'testOutputPath';
+    webpackMock.statsMock.compilation.compiler.outputPath = testOutputPath;
+    return module
+      .compile()
+      .then(() => {
+        expect(module.webpackOutputPath).to.equal(testOutputPath);
+        expect(module.originalServicePath).to.equal(testServicePath);
+        expect(module.serverless.config.servicePath).to.equal(testOutputPath);
+      });
+  });
+});
diff --git a/tests/run.test.js b/tests/run.test.js
new file mode 100644
index 0000000..9a3fbf0
--- /dev/null
+++ b/tests/run.test.js
@@ -0,0 +1,196 @@
+'use strict';
+
+const chai = require('chai');
+const sinon = require('sinon');
+const mockery = require('mockery');
+const Serverless = require('serverless');
+const makeWebpackMock = require('./webpack.mock');
+const makeUtilsMock = require('./utils.mock');
+chai.use(require('sinon-chai'));
+const expect = chai.expect;
+
+describe('run', () => {
+  let webpackMock;
+  let utilsMock;
+  let baseModule;
+  let module;
+  let serverless;
+
+  before(() => {
+    mockery.enable({ warnOnUnregistered: false });
+    webpackMock = makeWebpackMock();
+    utilsMock = makeUtilsMock();
+    mockery.registerMock('webpack', webpackMock);
+    mockery.registerMock('./utils', utilsMock);
+    baseModule = require('../lib/run');
+  });
+
+  after(() => {
+    mockery.disable();
+    mockery.deregisterAll();
+  });
+
+  beforeEach(() => {
+    serverless = new Serverless();
+    serverless.cli = { log: sinon.spy() };
+    webpackMock._resetSpies();
+    utilsMock._resetSpies();
+    module = Object.assign({
+      serverless,
+      options: {},
+    }, baseModule);
+  });
+
+  describe('utils', () => {
+    it('should expose utils methods', () => {
+      expect(module.loadHandler).to.be.a('function');
+      expect(module.getEvent).to.be.a('function');
+      expect(module.getContext).to.be.a('function');
+    });
+
+    it('should require the output file with `loadHandler`', () => {
+      const testPath = '/testpath';
+      const testFilename = 'testfilename';
+      const testModuleName = `${testPath}/${testFilename}`;
+      const testStats = {
+        compilation: {
+          options: {
+            output: {
+              path: testPath,
+              filename: testFilename,
+            },
+          },
+        },
+      };
+      const testModule = {};
+      mockery.registerMock(testModuleName, testModule);
+      const res = module.loadHandler(testStats);
+      mockery.deregisterMock(testModuleName);
+      expect(res).to.equal(testModule);
+      expect(utilsMock.purgeCache).to.have.callCount(1);
+    });
+
+    it('should return a default event with `getEvent` and no option path', () => {
+      module.options.path = null;
+      const res = module.getEvent();
+      expect(res).to.equal(null);
+    });
+
+    it('should load an event object from disk with `getEvent`', () => {
+      const testPath = 'testPath';
+      module.options.path = testPath;
+      const testExampleObject = {};
+      module.serverless.utils.readFileSync = sinon.stub().returns(testExampleObject);
+      const res = module.getEvent();
+      expect(res).to.equal(testExampleObject);
+    });
+
+    it('should return an context object with `getContext`', () => {
+      const testFunctionName = 'testFunctionName';
+      const res = module.getContext(testFunctionName);
+      expect(res).to.eql({
+        awsRequestId: 'testguid',
+        functionName: testFunctionName,
+        functionVersion: '$LATEST',
+        invokeid: 'testguid',
+        isDefaultFunctionVersion: true,
+        logGroupName: `/aws/lambda/${testFunctionName}`,
+        logStreamName: '2016/02/14/[HEAD]13370a84ca4ed8b77c427af260',
+        memoryLimitInMB: '1024',
+      });
+    });
+  });
+
+  describe('run', () => {
+    const testEvent = {};
+    const testContext = {};
+    const testStats = {};
+    const testFunctionId = 'testFunctionId';
+    const testFunctionResult = 'testFunctionResult';
+    const testModule = {
+      [testFunctionId]: null,
+    };
+
+    beforeEach(() => {
+      module.options['function'] = testFunctionId;
+      module.loadHandler = sinon.stub().returns(testModule);
+      module.getEvent = sinon.stub().returns(testEvent);
+      module.getContext = sinon.stub().returns(testContext);
+    });
+
+    it('should execute the given function handler', () => {
+      const testFunction = sinon.spy((e, c, cb) => cb(null, testFunctionResult));
+      testModule[testFunctionId] = testFunction;
+      return module
+        .run(testStats)
+        .then((res) => {
+          expect(res).to.equal(testFunctionResult);
+          expect(testFunction).to.have.been.calledWith(
+            testEvent,
+            testContext
+          );
+        });
+    });
+
+    it('should fail if the function handler returns an error', () => {
+      const testError = 'testError';
+      const testFunction = sinon.spy((e, c, cb) => cb(testError));
+      testModule[testFunctionId] = testFunction;
+      return module
+        .run(testStats)
+        .catch((res) => {
+          expect(res).to.equal(testError);
+        });
+    });
+  });
+
+  describe('watch', () => {
+    const testEvent = {};
+    const testContext = {};
+    const testStats = {};
+    const testFunctionId = 'testFunctionId';
+    const testFunctionResult = 'testFunctionResult';
+    const testModule = {
+      [testFunctionId]: null,
+    };
+
+    beforeEach(() => {
+      module.options['function'] = testFunctionId;
+      module.loadHandler = sinon.stub().returns(testModule);
+      module.getEvent = sinon.stub().returns(testEvent);
+      module.getContext = sinon.stub().returns(testContext);
+    });
+
+    it('should throw if webpack watch fails', () => {
+      const testError = 'testError';
+      webpackMock.compilerMock.watch = sinon.spy((opt, cb) => cb(testError));
+      expect(module.watch.bind(module)).to.throw(testError);
+    });
+
+    it('should throw if function handler fails', () => {
+      const testError = 'testHandlerError';
+      const testFunction = sinon.spy((e, c, cb) => cb(testError));
+      testModule[testFunctionId] = testFunction;
+      let testCb;
+      webpackMock.compilerMock.watch = sinon.spy((opt, cb) => {
+        testCb = cb;
+        cb(null, webpackMock.statsMock);
+      });
+      expect(module.watch.bind(module)).to.throw(testError);
+    });
+
+    it('should call the handler every time a compilation occurs', () => {
+      const testFunction = sinon.spy((e, c, cb) => cb(null, testFunctionResult));
+      testModule[testFunctionId] = testFunction;
+      let testCb;
+      webpackMock.compilerMock.watch = sinon.spy((opt, cb) => {
+        testCb = cb;
+        cb(null, webpackMock.statsMock);
+      });
+      module.watch();
+      expect(testFunction).to.have.callCount(1);
+      testCb(null, webpackMock.statsMock);
+      expect(testFunction).to.have.callCount(2);
+    });
+  });
+});
diff --git a/tests/utils.mock.js b/tests/utils.mock.js
new file mode 100644
index 0000000..f38c37c
--- /dev/null
+++ b/tests/utils.mock.js
@@ -0,0 +1,15 @@
+'use strict';
+
+const sinon = require('sinon');
+
+module.exports = () => ({
+  _resetSpies() {
+    for (let p in this) {
+      if (this.hasOwnProperty(p) && p !== '_resetSpies') {
+        this[p].reset();
+      }
+    }
+  },
+  guid: sinon.stub().returns('testguid'),
+  purgeCache: sinon.spy(),
+});
diff --git a/tests/webpack.mock.js b/tests/webpack.mock.js
new file mode 100644
index 0000000..15fe4cc
--- /dev/null
+++ b/tests/webpack.mock.js
@@ -0,0 +1,33 @@
+'use strict';
+
+const sinon = require('sinon');
+
+const statsMockBase = () => ({
+  compilation: {
+    errors: [],
+    compiler: {
+      outputPath: 'statsMock-outputPath',
+    },
+  },
+  toString: () => 'testStats',
+});
+
+const statsMock = {};
+
+Object.assign(statsMock, statsMockBase());
+
+const compilerMock = {
+  run: sinon.spy((cb) => cb(null, statsMock)),
+  watch: sinon.spy((opt, cb) => cb(null, statsMock)),
+};
+
+const webpackMock = sinon.stub().returns(compilerMock);
+webpackMock.statsMock = statsMock;
+webpackMock.compilerMock = compilerMock;
+webpackMock._resetSpies = () => {
+  webpackMock.reset();
+  compilerMock.run.reset();
+  Object.assign(statsMock, statsMockBase());
+};
+
+module.exports = () => webpackMock;