diff --git a/.eslintrc.js b/.eslintrc.js
new file mode 100644
index 0000000..a1c1525
--- /dev/null
+++ b/.eslintrc.js
@@ -0,0 +1,6 @@
+module.exports = {
+  "extends": "airbnb-base",
+  "env": {
+    "mocha": true
+  }
+};
\ No newline at end of file
diff --git a/.travis.yml b/.travis.yml
index 24a8ab9..efb0983 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,3 +1,3 @@
 language: node_js
 node_js:
-  - "5"
+  - "8"
diff --git a/lib/RequestMiddleware.js b/lib/RequestMiddleware.js
index ab51b8a..736f941 100644
--- a/lib/RequestMiddleware.js
+++ b/lib/RequestMiddleware.js
@@ -1,41 +1,22 @@
-var digest = require('./digest')
-var jsonDB = require('./jsonDb')
+/* eslint-disable no-param-reassign */
+const digest = require('./digest');
+const jsonDB = require('./jsonDb');
 
-function loadFixture(cassettePath, axiosConfig) {
-  var requestKey = digest(axiosConfig)
-  return jsonDB.loadAt(cassettePath, requestKey)
-}
+const loadFixture = (cassettePath, axiosConfig) => {
+  const requestKey = digest(axiosConfig);
+  return jsonDB.loadAt(cassettePath, requestKey);
+};
 
-function injectVCRHeader(axiosConfig) {
-  // This is done like this because Axios injects a custom User-Agent in
-  // the request config if it hasn't been defined by the client.
-  //
-  // We need to do the same thing and inject our own so Axios doesn't modify
-  // the request config object at a later point (which breaks our logic because
-  // digests will be different at request and response times)
+exports.success = cassettePath =>
+  axiosConfig =>
+    loadFixture(cassettePath, axiosConfig)
+      .then((cassette) => {
+        axiosConfig.adapter = () =>
+          new Promise((resolve) => {
+            cassette.originalResponseData.fixture = true;
+            return resolve(cassette.originalResponseData);
+          });
+        return axiosConfig;
+      }).catch(() => axiosConfig);
 
-  var headers = axiosConfig.headers
-  if (!headers['User-Agent'] && !headers['user-agent']) {
-    headers['User-Agent'] = 'axios-vcr'
-  }
-}
-
-exports.success = function (cassettePath) {
-  return function(axiosConfig) {
-    injectVCRHeader(axiosConfig)
-
-    return loadFixture(cassettePath, axiosConfig).then(function(cassette) {
-      axiosConfig.adapter = function(resolve, _reject, _cfg) {
-        cassette.originalResponseData.fixture = true
-        return resolve(cassette.originalResponseData)
-      }
-      return axiosConfig
-    }).catch(function(err) {
-      return axiosConfig
-    })
-  }
-}
-
-exports.failure = function(error) {
-  return Promise.reject(error)
-}
+exports.failure = error => Promise.reject(error);
diff --git a/lib/ResponseMiddleware.js b/lib/ResponseMiddleware.js
index bddd44c..2576b9a 100644
--- a/lib/ResponseMiddleware.js
+++ b/lib/ResponseMiddleware.js
@@ -1,16 +1,16 @@
-var jsonDB = require('./jsonDb')
-var digest = require('./digest')
+const jsonDB = require('./jsonDb');
+const digest = require('./digest');
 
-function serialize(response) {
-  var meta = {
+const serialize = (response) => {
+  const meta = {
     url: response.config.url,
     method: response.config.method,
     data: response.config.data,
-    headers: response.config.headers
-  }
+    headers: response.config.headers,
+  };
 
   return {
-    meta: meta,
+    meta,
     fixture: true,
 
     originalResponseData: {
@@ -18,28 +18,24 @@ function serialize(response) {
       statusText: response.statusText,
       headers: response.headers,
       data: response.data,
-      config: meta
-    }
-  }
-}
+      config: meta,
+    },
+  };
+};
 
-function storeFixture(cassettePath, response) {
-  var requestKey = digest(response.config)
-  var fixture = serialize(response)
-  return jsonDB.writeAt(cassettePath, requestKey, fixture)
-}
+const storeFixture = (cassettePath, response) => {
+  const requestKey = digest(response.config);
+  const fixture = serialize(response);
+  return jsonDB.writeAt(cassettePath, requestKey, fixture);
+};
 
-exports.success = function (cassettePath) {
-  return function(res) {
-    if (res.fixture)
-      return res
+exports.success = cassettePath =>
+  (res) => {
+    if (res.fixture) {
+      return res;
+    }
 
-    return storeFixture(cassettePath, res).then(function() {
-      return res
-    })
-  }
-}
+    return storeFixture(cassettePath, res).then(() => res);
+  };
 
-exports.failure = function(error) {
-  return Promise.reject(error)
-}
+exports.failure = error => Promise.reject(error);
diff --git a/lib/digest.js b/lib/digest.js
index f40a5d0..afe352f 100644
--- a/lib/digest.js
+++ b/lib/digest.js
@@ -1,21 +1,44 @@
-var md5 = require('md5')
-var _ = require('lodash')
+const md5 = require('md5');
+const _ = require('lodash');
 
-function key(axiosConfig) {
-  //Content-Length is calculated automatically by Axios before sending a request
-  //We don't want to include it here because it could be changed by axios
+const key = (args) => {
+  const {
+    baseURL, method, data, transformRequest,
+  } = args;
+  let { url, headers = {} } = args;
+  // Flatten headers
+  // Same happening in dispatchResponse.js
 
-
-  var baseConfig = {
-    url: axiosConfig.url,
-    method: axiosConfig.method,
-    data: axiosConfig.data,
-    headers: _.omit(axiosConfig.headers, [
-      'Content-Length', 'content-length'
-    ])
+  // Support baseURL config
+  if (baseURL && !/^([a-z][a-z\d+\-.]*:)?\/\//i.test(url)) {
+    url = url
+      ? `${baseURL.replace(/\/+$/, '')}/${url.replace(/^\/+/, '')}`
+      : baseURL;
   }
 
-  return md5(JSON.stringify(baseConfig))
-}
+  headers = _.merge(
+    headers.common || {},
+    headers[method] || {},
+    headers || {},
+  );
+
+  headers = _.omit(
+    headers,
+    ['delete', 'get', 'head', 'post', 'put', 'patch', 'common',
+      // Content-Length is calculated automatically by Axios before sending a request
+      // We don't want to include it here because it could be changed by axios
+      'Content-Length', 'content-length',
+    ],
+  );
+
+  const baseConfig = {
+    url,
+    method,
+    data: _.values(transformRequest).reduce((nextData, fn) => fn(nextData, headers), data),
+    headers,
+  };
+
+  return md5(JSON.stringify(baseConfig));
+};
 
-module.exports = key
+module.exports = key;
diff --git a/lib/jsonDb.js b/lib/jsonDb.js
index 8c33403..d6101c5 100644
--- a/lib/jsonDb.js
+++ b/lib/jsonDb.js
@@ -1,35 +1,38 @@
-var fs = require('fs-promise')
-var _ = require('lodash')
-var mkdirp = require('mkdirp')
-var getDirName = require('path').dirname
-
-function loadAt(filePath, jsonPath) {
-  return fs.readJson(filePath).then(function(json) {
-    if (_.isUndefined(jsonPath))
-      return json
-
-    var value = _.get(json, jsonPath)
-    if (!_.isUndefined(value))
-      return value
-    else
-      throw "Invalid JSON Path"
-  })
-}
-
-function writeAt(filePath, jsonPath, value) {
-  mkdirp.sync(getDirName(filePath))
-
-  return fs.readJson(filePath).then(function(json) {
-    _.set(json, jsonPath, value)
-    return fs.writeJson(filePath, json)
-  }).catch(function(error) {
-    var json = {}
-    _.set(json, jsonPath, value)
-    return fs.writeJson(filePath, json)
-  })
-}
+
+const _ = require('lodash');
+const mkdirp = require('mkdirp');
+const getDirName = require('path').dirname;
+
+const { readJson, writeJson } = require('./readWriteJson');
+
+const loadAt = (filePath, jsonPath) =>
+  readJson(filePath).then((json) => {
+    if (_.isUndefined(jsonPath)) {
+      return json;
+    }
+
+    const value = _.get(json, jsonPath);
+    if (!_.isUndefined(value)) {
+      return value;
+    }
+
+    throw new Error('Invalid JSON Path');
+  });
+
+const writeAt = (filePath, jsonPath, value) => {
+  mkdirp.sync(getDirName(filePath));
+
+  return readJson(filePath).then((json) => {
+    _.set(json, jsonPath, value);
+    return writeJson(filePath, json);
+  }).catch(() => {
+    const json = {};
+    _.set(json, jsonPath, value);
+    return writeJson(filePath, json);
+  });
+};
 
 module.exports = {
-  loadAt: loadAt,
-  writeAt: writeAt
-}
+  loadAt,
+  writeAt,
+};
diff --git a/lib/readWriteJson.js b/lib/readWriteJson.js
new file mode 100644
index 0000000..53c1c56
--- /dev/null
+++ b/lib/readWriteJson.js
@@ -0,0 +1,9 @@
+const util = require('util');
+const fs = require('fs');
+
+const readFile = util.promisify(fs.readFile);
+const writeFile = util.promisify(fs.writeFile);
+const readJson = filePath => readFile(filePath, 'utf8').then(data => JSON.parse(data));
+const writeJson = (filePath, json) => writeFile(filePath, JSON.stringify(json));
+
+module.exports = { readJson, writeJson };
diff --git a/mocha.opts b/mocha.opts
new file mode 100644
index 0000000..fb7f43c
--- /dev/null
+++ b/mocha.opts
@@ -0,0 +1 @@
+--require test/setup.js
\ No newline at end of file
diff --git a/package.json b/package.json
index 2a28d0f..fce6f56 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,8 @@
   "main": "index.js",
   "homepage": "http://github.com/nettofarah/axios-vcr",
   "scripts": {
-    "test": "mocha test/"
+    "test": "npm run lint && mocha test/",
+    "lint": "eslint test/ lib/"
   },
   "bugs": {
     "url": "https://github.com/nettofarah/axios-vcr/issues"
@@ -15,9 +16,9 @@
     "url": "https://github.com/nettofarah/axios-vcr.git"
   },
   "files": [
-   "index.js",
-   "lib"
- ],
+    "index.js",
+    "lib"
+  ],
   "keywords": [
     "axios",
     "vcr",
@@ -28,12 +29,17 @@
   "author": "Netto Farah",
   "license": "MIT",
   "devDependencies": {
-    "axios": "^0.11.1",
+    "axios": "^0.17.0",
+    "eslint": "^4.10.0",
+    "eslint-config-airbnb-base": "^12.1.0",
+    "eslint-plugin-import": "^2.8.0",
     "mocha": "^2.5.3",
     "rimraf": "^2.5.2"
   },
+  "peerDependencies": {
+    "axios": "^0.17.0"
+  },
   "dependencies": {
-    "fs-promise": "^0.5.0",
     "lodash": "^4.13.1",
     "md5": "^2.1.0",
     "mkdirp": "^0.5.1"
diff --git a/test/axios_vcr_test.js b/test/axios_vcr_test.js
index a85a0a8..b79b81c 100644
--- a/test/axios_vcr_test.js
+++ b/test/axios_vcr_test.js
@@ -1,158 +1,172 @@
-var fs = require('fs')
-var rimraf = require('rimraf')
-var assert = require('assert')
-var VCR = require('../index')
-var _ = require('lodash')
+/* eslint-disable func-names */
+const fs = require('fs');
+const rimraf = require('rimraf');
+const assert = require('assert');
+const VCR = require('../index');
+const _ = require('lodash');
+const axios = require('axios');
+
+const { loadAt } = require('../lib/jsonDb');
+const digest = require('../lib/digest');
 
 function clearFixtures() {
-  rimraf.sync('./test/fixtures')
+  rimraf.sync('./test/fixtures');
 }
 
 function fileExists(path) {
   try {
-    return fs.statSync(path).isFile()
-  } catch(e) {
-    return false
+    return fs.statSync(path).isFile();
+  } catch (e) {
+    return false;
   }
 }
 
 function getFixture(cassettePath, config) {
-  var loadAt = require('../lib/jsonDb').loadAt
-  var digest = require('../lib/digest')
-  var key = digest(config)
+  const key = digest(config);
 
-  return loadAt(cassettePath, key)
+  return loadAt(cassettePath, key);
 }
 
-describe('Axios VCR', function() {
-  this.timeout(10000)
-  var posts = 'http://jsonplaceholder.typicode.com/posts/1'
-  var axios = require('axios')
-
-  describe('recording', function() {
-    beforeEach(clearFixtures)
-    afterEach(clearFixtures)
-
-    it('generates stubs for requests', function(done) {
-      var path = './test/fixtures/posts.json'
-      VCR.mountCassette(path)
-
-      axios.get(posts).then(function(response) {
-        getFixture(path, response.config).then(function(fixture) {
-          assert.deepEqual(fixture.originalResponseData.data, response.data)
-          done()
-          VCR.ejectCassette(path)
-        })
-      })
-    })
-
-    it('works with nested folders', function(done) {
-      var cassettePath = './test/fixtures/nested/posts.json'
-      VCR.mountCassette(cassettePath)
-
-      axios.get(posts).then(function(response) {
-        getFixture(cassettePath, response.config).then(function(fixture) {
-          assert.deepEqual(fixture.originalResponseData.data, response.data)
-          done()
-
-          VCR.ejectCassette(cassettePath)
-        })
-      }).catch(function(err) { console.log(err) })
-    })
-
-    it('stores headers and status', function(done) {
-      var cassettePath = './test/fixtures/posts.json'
-      VCR.mountCassette(cassettePath)
-
-      axios.get(posts).then(function(response) {
-        getFixture(cassettePath, response.config).then(function(fixture) {
-          assert.deepEqual(fixture.originalResponseData.headers, response.headers)
-          assert.equal(fixture.originalResponseData.status, response.status)
-          assert.equal(fixture.originalResponseData.statusText, response.statusText)
-          done()
-
-          VCR.ejectCassette(cassettePath)
-        })
-      })
-    })
-  })
-
-  describe('replaying', function() {
+describe('Axios VCR', function () {
+  this.timeout(10000);
+
+  const posts = 'http://jsonplaceholder.typicode.com/posts/1';
+
+  describe('recording', () => {
+    beforeEach(clearFixtures);
+    afterEach(clearFixtures);
+
+    it('generates stubs for requests', () => {
+      const path = './test/fixtures/posts.json';
+      VCR.mountCassette(path);
+
+      return axios.get(posts).then(response =>
+        getFixture(path, response.config)
+          .then((fixture) => {
+            assert.deepEqual(fixture.originalResponseData.data, response.data);
+          })).finally(() => VCR.ejectCassette(path));
+    });
+
+    it('works with nested folders', () => {
+      const cassettePath = './test/fixtures/nested/posts.json';
+      VCR.mountCassette(cassettePath);
+
+      return axios
+        .get(posts)
+        .then(response =>
+          getFixture(cassettePath, response.config)
+            .then((fixture) => {
+              assert.deepEqual(fixture.originalResponseData.data, response.data);
+            }))
+        .finally(() => {
+          VCR.ejectCassette(cassettePath);
+        });
+    });
+
+    it('stores headers and status', () => {
+      const cassettePath = './test/fixtures/posts.json';
+      VCR.mountCassette(cassettePath);
+
+      return axios.get(posts).then(response =>
+        getFixture(cassettePath, response.config).then((fixture) => {
+          assert.deepEqual(
+            fixture.originalResponseData.headers,
+            response.headers,
+          );
+          assert.equal(fixture.originalResponseData.status, response.status);
+          assert.equal(
+            fixture.originalResponseData.statusText,
+            response.statusText,
+          );
+        })).finally(() => VCR.ejectCassette(cassettePath));
+    });
+  });
+
+  describe('replaying', () => {
     /*
       This is a tricky test.
       I'm not aware of any way to check that a network request has been made.
       So instead we hit an unexisting URL that is backed by a cassette. We can now
       check that the response is the same as the cassette file.
     */
-    it('skips remote calls', function(done) {
-      var path = './test/static_fixtures/posts.json'
-      assert(fileExists(path))
-
-      var url = 'http://something.com/unexisting'
-      VCR.mountCassette(path)
-
-      axios.get(url).then(function(res) {
-        getFixture(path, res.config).then(function(fixture) {
-          assert.deepEqual(fixture.originalResponseData, _.omit(res, 'fixture'))
-          done()
-
-          VCR.ejectCassette(path)
-        }).catch(err => { console.log(err); done() })
-      })
-    })
-
-    it('makes remote call when a cassette is not available', function(done) {
-      var path = './test/static_fixtures/no_posts.json'
+    it('skips remote calls', () => {
+      const path = './test/static_fixtures/posts.json';
+      assert(fileExists(path));
+
+      const url = 'http://something.com/unexisting';
+      VCR.mountCassette(path);
+
+      return axios
+        .get(url)
+        .then(res =>
+          getFixture(path, res.config)
+            .then((fixture) => {
+              assert.deepEqual(
+                fixture.originalResponseData,
+                _.omit(res, 'fixture'),
+              );
+            })).finally(() => VCR.ejectCassette(path));
+    });
+
+    it('makes remote call when a cassette is not available', () => {
+      const path = './test/static_fixtures/no_posts.json';
 
       try {
-        fs.unlinkSync(path)
-      } catch(e) {}
-
-      assert(!fileExists(path))
-      VCR.mountCassette(path)
-
-      axios.get(posts).then(function(response) {
-        assert.equal(200, response.status)
-        fs.unlinkSync(path)
-        done()
-
-        VCR.ejectCassette(path)
-      })
-    })
-  })
-
-  describe('Multiple Requests', function() {
-    this.timeout(15000)
-
-    beforeEach(clearFixtures)
-    afterEach(clearFixtures)
-
-    var usersUrl = 'http://jsonplaceholder.typicode.com/users'
-    var todosUrl = 'http://jsonplaceholder.typicode.com/todos'
-
-    it('stores multiple requests in the same cassette', function(done) {
-      var path = './test/fixtures/multiple.json'
-
-      VCR.mountCassette(path)
-
-      var usersPromise = axios.get(usersUrl)
-      var todosPromise = axios.get(todosUrl)
-
-      Promise.all([usersPromise, todosPromise]).then(function(responses) {
-        var usersResponse = responses[0]
-        var todosResponse = responses[1]
-
-        var usersResponsePromise = getFixture(path, usersResponse.config)
-        var todosResponsePromise = getFixture(path, todosResponse.config)
-
-        Promise.all([usersResponsePromise, todosResponsePromise]).then(function(fixtures) {
-          assert.deepEqual(fixtures[0].originalResponseData.data, usersResponse.data)
-          assert.deepEqual(fixtures[1].originalResponseData.data, todosResponse.data)
-          done()
-
-          VCR.ejectCassette(path)
-        })
-      })
-    })
-  })
-})
+        fs.unlinkSync(path);
+      } catch (e) {
+        // Do nothing
+      }
+
+      assert(!fileExists(path));
+      VCR.mountCassette(path);
+
+      return axios.get(posts).then((response) => {
+        assert.equal(200, response.status);
+      }).finally(() => {
+        fs.unlinkSync(path);
+        VCR.ejectCassette(path);
+      });
+    });
+  });
+
+  describe('Multiple Requests', function () {
+    this.timeout(15000);
+
+    beforeEach(clearFixtures);
+    afterEach(clearFixtures);
+
+    const usersUrl = 'http://jsonplaceholder.typicode.com/users';
+    const todosUrl = 'http://jsonplaceholder.typicode.com/todos';
+
+    it('stores multiple requests in the same cassette', (done) => {
+      const path = './test/fixtures/multiple.json';
+
+      VCR.mountCassette(path);
+
+      const usersPromise = axios.get(usersUrl);
+      const todosPromise = axios.get(todosUrl);
+
+      Promise.all([usersPromise, todosPromise]).then((responses) => {
+        const usersResponse = responses[0];
+        const todosResponse = responses[1];
+
+        const usersResponsePromise = getFixture(path, usersResponse.config);
+        const todosResponsePromise = getFixture(path, todosResponse.config);
+
+        Promise.all([usersResponsePromise, todosResponsePromise]).then((fixtures) => {
+          assert.deepEqual(
+            fixtures[0].originalResponseData.data,
+            usersResponse.data,
+          );
+          assert.deepEqual(
+            fixtures[1].originalResponseData.data,
+            todosResponse.data,
+          );
+          done();
+
+          VCR.ejectCassette(path);
+        });
+      });
+    });
+  });
+});
diff --git a/test/digest_test.js b/test/digest_test.js
index 0ae5c9c..a53563f 100644
--- a/test/digest_test.js
+++ b/test/digest_test.js
@@ -1,31 +1,30 @@
-var digest = require('../lib/digest')
-var md5 = require('md5')
-var assert = require('assert')
-var _ = require('lodash')
+const digest = require('../lib/digest');
+const md5 = require('md5');
+const assert = require('assert');
+const _ = require('lodash');
 
 function testDigest(cfg) {
-  var config = _.pick(cfg, ['url', 'method', 'data', 'headers'])
-  return md5(JSON.stringify(config))
+  const config = _.pick(cfg, ['url', 'method', 'data', 'headers']);
+  return md5(JSON.stringify(config));
 }
 
-describe('Digest', function() {
-
-  it('md5s certain parameters from an axiosConfig object', function() {
-    var sampleConfig = {
+describe('Digest', () => {
+  it('md5s certain parameters from an axiosConfig object', () => {
+    const sampleConfig = {
       url: 'http://cats.com',
       method: 'get',
       data: {},
       headers: {
-        'user-agent': 'test'
+        'user-agent': 'test',
       },
       extraProperty: 'bla',
-      somethingElse: 'irrelevant'
-    }
+      somethingElse: 'irrelevant',
+    };
 
-    var fullDigest = md5(JSON.stringify(sampleConfig))
-    var expectedDigest = digest(sampleConfig)
+    const fullDigest = md5(JSON.stringify(sampleConfig));
+    const expectedDigest = digest(sampleConfig);
 
-    assert.notEqual(fullDigest, expectedDigest)
-    assert.equal(testDigest(sampleConfig), expectedDigest)
-  })
-})
+    assert.notEqual(fullDigest, expectedDigest);
+    assert.equal(testDigest(sampleConfig), expectedDigest);
+  });
+});
diff --git a/test/jsonDb_test.js b/test/jsonDb_test.js
index 128461f..ea0386d 100644
--- a/test/jsonDb_test.js
+++ b/test/jsonDb_test.js
@@ -1,106 +1,95 @@
-var jsonDB = require('../lib/jsonDb')
-var assert = require('assert')
-var fs = require('fs-promise')
-var rimraf = require('rimraf')
+const assert = require('assert');
+const rimraf = require('rimraf');
+
+const jsonDB = require('../lib/jsonDb');
+const { writeJson } = require('../lib/readWriteJson');
+
 
 function clearFixtures() {
-  rimraf.sync('./test/jdb/*')
+  rimraf.sync('./test/jdb/*');
 }
 
-describe('JsonDB', function() {
-  afterEach(clearFixtures)
+describe('JsonDB', () => {
+  afterEach(clearFixtures);
 
-  describe('loadAt', function() {
-    var path = './test/jdb/temp.json'
+  describe('loadAt', () => {
+    const path = './test/jdb/temp.json';
 
-    beforeEach(function() {
-      fs.writeJsonSync(path, {
+    beforeEach(() =>
+      writeJson(path, {
         a: {
           b: {
-            c: 'it works!'
-          }
-        }
-      })
-    })
-
-    it('loads an object from a JSON stored in a file', function(done) {
-      jsonDB.loadAt(path).then(function(payload) {
+            c: 'it works!',
+          },
+        },
+      }));
+
+    it('loads an object from a JSON stored in a file', () =>
+      jsonDB.loadAt(path).then((payload) => {
         assert.deepEqual(payload, {
           a: {
             b: {
-              c: 'it works!'
-            }
-          }
-        })
-        done()
-      })
-    })
-
-    it('accepts nested paths', function(done) {
-      jsonDB.loadAt(path, 'a.b.c').then(function(payload) {
-        assert.equal(payload, 'it works!')
-        done()
-      })
-    })
-
-    it('fails when the file does not exist', function(done) {
-      jsonDB.loadAt('./test/jdb/unexisting.json').catch(function(error) {
-        assert.equal(error.code, 'ENOENT')
-        done()
-      })
-    })
-
-    it('fails when the json path does not exist', function(done) {
-      jsonDB.loadAt('./test/jdb/temp.json', 'a.b.c.d').catch(function(error) {
-        assert.equal(error, 'Invalid JSON Path')
-        done()
-      })
-    })
-  })
-
-  describe('writeAt', function() {
-    var path = './test/jdb/temp_write.json'
-
-    beforeEach(function() {
-      fs.writeJsonSync(path, {
+              c: 'it works!',
+            },
+          },
+        });
+      }));
+
+    it('accepts nested paths', () =>
+      jsonDB.loadAt(path, 'a.b.c').then((payload) => {
+        assert.equal(payload, 'it works!');
+      }));
+
+    it('fails when the file does not exist', () =>
+      jsonDB.loadAt('./test/jdb/unexisting.json').catch((error) => {
+        assert.equal(error.code, 'ENOENT');
+      }));
+
+    it('fails when the json path does not exist', () =>
+      jsonDB.loadAt('./test/jdb/temp.json', 'a.b.c.d').catch((error) => {
+        assert.deepEqual(error, new Error('Invalid JSON Path'));
+      }));
+  });
+
+  describe('writeAt', () => {
+    const path = './test/jdb/temp_write.json';
+
+    beforeEach(() =>
+      writeJson(path, {
         a: {
-          b: {}
-        }
-      })
-    })
-
-    it('writes at a given path', function(done) {
-      var time = new Date().getTime()
-      var payload = { c: 'Axios VCR', time: time }
-
-      jsonDB.writeAt(path, 'a.b', payload).then(function() {
-        jsonDB.loadAt(path, 'a.b').then(function(json) {
-          assert.deepEqual(payload, json)
-          done()
-        })
-      })
-    })
-
-    it('creates missing keys', function(done) {
-      var payload = 'nested stuff'
-      jsonDB.writeAt(path, 'a.b.c.d.e', payload).then(function() {
-        jsonDB.loadAt(path, 'a.b.c.d.e').then(function(json) {
-          assert.deepEqual(payload, json)
-          done()
-        })
-      })
-    })
-
-    it('creates missing parts of the path', function(done) {
-      var path = './test/jdb/nested/temp_write.json'
-      var payload = 'something'
-
-      jsonDB.writeAt(path, 'a', payload).then(function() {
-        jsonDB.loadAt(path, 'a').then(function(json) {
-          assert.deepEqual(payload, json)
-          done()
-        })
-      })
-    })
-  })
-})
+          b: {},
+        },
+      }));
+
+    it('writes at a given path', () => {
+      const time = new Date().getTime();
+      const payload = { c: 'Axios VCR', time };
+
+      return jsonDB.writeAt(path, 'a.b', payload).then(() => {
+        jsonDB.loadAt(path, 'a.b').then((json) => {
+          assert.deepEqual(payload, json);
+        });
+      });
+    });
+
+    it('creates missing keys', () => {
+      const payload = 'nested stuff';
+      return jsonDB.writeAt(path, 'a.b.c.d.e', payload).then(() => {
+        jsonDB.loadAt(path, 'a.b.c.d.e').then((json) => {
+          assert.deepEqual(payload, json);
+        });
+      });
+    });
+
+    it('creates missing parts of the path', () => {
+      const tempWritePath = './test/jdb/nested/temp_write.json';
+      const payload = 'something';
+
+      return jsonDB.writeAt(tempWritePath, 'a', payload).then(() => {
+        jsonDB.loadAt(tempWritePath, 'a').then((json) => {
+          assert.deepEqual(payload, json);
+        });
+      });
+    });
+  });
+});
diff --git a/test/promise-finally-polyfill.js b/test/promise-finally-polyfill.js
new file mode 100644
index 0000000..e215ebf
--- /dev/null
+++ b/test/promise-finally-polyfill.js
@@ -0,0 +1,47 @@
+/* eslint-disable no-extend-native */
+
+if (typeof Promise !== 'function') {
+  throw new TypeError('A global Promise is required');
+}
+
+if (typeof Promise.prototype.finally !== 'function') {
+  const speciesConstructor = (O, defaultConstructor) => {
+    if (!O || (typeof O !== 'object' && typeof O !== 'function')) {
+      throw new TypeError('Assertion failed: Type(O) is not Object');
+    }
+    const C = O.constructor;
+    if (typeof C === 'undefined') {
+      return defaultConstructor;
+    }
+    if (!C || (typeof C !== 'object' && typeof C !== 'function')) {
+      throw new TypeError('O.constructor is not an Object');
+    }
+    const S = typeof Symbol === 'function' && typeof Symbol.species === 'symbol' ? C[Symbol.species] : undefined;
+    if (S === null) {
+      return defaultConstructor;
+    }
+    if (typeof S === 'function' && S.prototype) {
+      return S;
+    }
+    throw new TypeError('no constructor found');
+  };
+
+  const shim = {
+    finally(onFinally) {
+      const promise = this;
+      if (typeof promise !== 'object' || promise === null) {
+        throw new TypeError('"this" value is not an Object');
+      }
+      const C = speciesConstructor(promise, Promise); // throws if SpeciesConstructor throws
+      const handler = typeof onFinally === 'function' ? onFinally : () => {};
+      return Promise.prototype.then.call(
+        promise,
+        x => new C(resolve => resolve(handler())).then(() => x),
+        e => new C(resolve => resolve(handler())).then(() => {
+          throw e;
+        }),
+      );
+    },
+  };
+  Object.defineProperty(Promise.prototype, 'finally', { configurable: true, writable: true, value: shim.finally });
+}
diff --git a/test/setup.js b/test/setup.js
new file mode 100644
index 0000000..5879a7f
--- /dev/null
+++ b/test/setup.js
@@ -0,0 +1 @@
+require('./promise-finally-polyfill');
diff --git a/test/static_fixtures/posts.json b/test/static_fixtures/posts.json
index 0f8e4f7..da92c33 100644
--- a/test/static_fixtures/posts.json
+++ b/test/static_fixtures/posts.json
@@ -1,11 +1,10 @@
 {
-  "6d51a168265ddf1c33f60fa111a26dc7": {
+  "56e7cedef2202ac3a46947b52d90a2d6": {
     "meta": {
       "url": "http://something.com/unexisting",
       "method": "get",
       "headers": {
-        "Accept": "application/json, text/plain, */*",
-        "User-Agent": "axios-vcr"
+        "Accept": "application/json, text/plain, */*"
       }
     },
     "fixture": true,
@@ -33,8 +32,7 @@
         "url": "http://something.com/unexisting",
         "method": "get",
         "headers": {
-          "Accept": "application/json, text/plain, */*",
-          "User-Agent": "axios-vcr"
+          "Accept": "application/json, text/plain, */*"
         }
       }
     }