diff --git a/README.md b/README.md
index 3c6141043a..5c8298e052 100644
--- a/README.md
+++ b/README.md
@@ -57,6 +57,7 @@ You can check the development status at the [Waffle Board](https://waffle.io/ipf
   - [Use in Node.js](#use-in-nodejs)
   - [Through command line tool](#through-command-line-tool)
   - [Use in the browser](#use-in-the-browser)
+  - [Use with Web Workers](#use-with-web-workers)
 - [Usage](#usage)
   - [IPFS CLI](#ipfs-cli)
   - [IPFS Daemon](#ipfs-daemon)
@@ -135,6 +136,20 @@ You can also load it using a `<script>` using the [unpkg](https://unpkg.com) CDN
 ```
 Inserting one of the above lines will make an `Ipfs` object available in the global namespace.
 
+### Use with Web Workers
+
+Some of the `ipfs.files.*` [MFS](https://github.com/ipfs/interface-ipfs-core/blob/master/SPEC/FILES.md#mutable-file-system) commands mutate the CID that corresponds to the current root of the file system. A read/write lock on the main thread prevents these mutations from conflicting. With single-process and [Node.js cluster](https://nodejs.org/api/cluster.html) based apps this is completely transparent but [Web Workers](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API) require a little extra setup.  Use the [`observable-webworkers`](https://www.npmjs.com/package/observable-webworkers) module to allow communication with any Web Workers your application creates:
+
+```javascript
+const observe = require('observable-webworkers')
+ 
+const worker = new Worker('my-worker-script.js')
+ 
+observe(worker)
+```
+
+`js-ipfs` will send extra messages to your Web Workers to orchestrate the read/write locks so please be aware of this in your Worker code.
+
 ## Usage
 
 ### IPFS CLI
diff --git a/examples/browser-script-tag/index.html b/examples/browser-script-tag/index.html
index 50ef0819e3..f95a295fd7 100644
--- a/examples/browser-script-tag/index.html
+++ b/examples/browser-script-tag/index.html
@@ -30,7 +30,7 @@ <h2>Some suggestions</h2>
   <code style="display:block; white-space:pre-wrap; background-color:#d7d6d6">
     node.files.add(new node.types.Buffer('Hello world!'), (err, filesAdded) => {
       if (err) {
-        return console.error('Error - ipfs files add', err, res)
+        return console.error('Error - ipfs add', err, res)
       }
 
       filesAdded.forEach((file) => console.log('successfully stored', file.hash))
diff --git a/examples/circuit-relaying/package.json b/examples/circuit-relaying/package.json
index 3e92c83f8a..6a3e5cf58d 100644
--- a/examples/circuit-relaying/package.json
+++ b/examples/circuit-relaying/package.json
@@ -18,7 +18,7 @@
     "ipfs-pubsub-room": "~0.3.0"
   },
   "devDependencies": {
-    "aegir": "^13.0.5",
+    "aegir": "^14.0.0",
     "http-server": "~0.10.0",
     "ipfs-css": "~0.2.0",
     "parcel-bundler": "^1.6.2",
diff --git a/package.json b/package.json
index 3c32ca819a..346b945742 100644
--- a/package.json
+++ b/package.json
@@ -66,6 +66,7 @@
     "chai": "^4.1.2",
     "delay": "^2.0.0",
     "detect-node": "^2.0.3",
+    "detect-webworker": "^1.0.0",
     "dir-compare": "^1.4.0",
     "dirty-chai": "^2.0.1",
     "eslint-plugin-react": "^7.7.0",
@@ -107,11 +108,12 @@
     "hoek": "^5.0.3",
     "human-to-milliseconds": "^1.0.0",
     "interface-datastore": "~0.4.1",
-    "ipfs-api": "^22.1.1",
+    "ipfs-api": "^22.2.1",
     "ipfs-bitswap": "~0.20.0",
     "ipfs-block": "~0.7.1",
     "ipfs-block-service": "~0.14.0",
     "ipfs-http-response": "~0.1.2",
+    "ipfs-mfs": "~0.0.13",
     "ipfs-multipart": "~0.1.0",
     "ipfs-repo": "~0.22.1",
     "ipfs-unixfs": "~0.1.15",
@@ -170,7 +172,8 @@
     "through2": "^2.0.3",
     "update-notifier": "^2.5.0",
     "yargs": "^11.0.0",
-    "yargs-parser": "^10.0.0"
+    "yargs-parser": "^10.0.0",
+    "yargs-promise": "^1.1.0"
   },
   "optionalDependencies": {
     "prom-client": "^11.0.0",
diff --git a/src/cli/bin.js b/src/cli/bin.js
index 2ccf2f66a0..3307b6e9ef 100755
--- a/src/cli/bin.js
+++ b/src/cli/bin.js
@@ -2,13 +2,14 @@
 
 'use strict'
 
+const YargsPromise = require('yargs-promise')
 const yargs = require('yargs')
 const updateNotifier = require('update-notifier')
 const readPkgUp = require('read-pkg-up')
-const fs = require('fs')
-const path = require('path')
 const utils = require('./utils')
 const print = utils.print
+const mfs = require('ipfs-mfs/cli')
+const debug = require('debug')('ipfs:cli')
 
 const pkg = readPkgUp.sync({cwd: __dirname}).pkg
 updateNotifier({
@@ -18,10 +19,6 @@ updateNotifier({
 
 const args = process.argv.slice(2)
 
-// Determine if the first argument is a sub-system command
-const commandNames = fs.readdirSync(path.join(__dirname, 'commands'))
-const isCommand = commandNames.includes(`${args[0]}.js`)
-
 const cli = yargs
   .option('silent', {
     desc: 'Write no output',
@@ -34,14 +31,6 @@ const cli = yargs
     type: 'string',
     default: ''
   })
-  .commandDir('commands', {
-    // Only include the commands for the sub-system we're using, or include all
-    // if no sub-system command has been passed.
-    include (path, filename) {
-      if (!isCommand) return true
-      return `${args[0]}.js` === filename
-    }
-  })
   .epilog(utils.ipfsPathHelp)
   .demandCommand(1)
   .fail((msg, err, yargs) => {
@@ -56,20 +45,6 @@ const cli = yargs
     yargs.showHelp()
   })
 
-// If not a sub-system command then load the top level aliases
-if (!isCommand) {
-  // NOTE: This creates an alias of
-  // `jsipfs files {add, get, cat}` to `jsipfs {add, get, cat}`.
-  // This will stay until https://github.com/ipfs/specs/issues/98 is resolved.
-  const addCmd = require('./commands/files/add')
-  const catCmd = require('./commands/files/cat')
-  const getCmd = require('./commands/files/get')
-  const aliases = [addCmd, catCmd, getCmd]
-  aliases.forEach((alias) => {
-    cli.command(alias.command, alias.describe, alias.builder, alias.handler)
-  })
-}
-
 // Need to skip to avoid locking as these commands
 // don't require a daemon
 if (args[0] === 'daemon' || args[0] === 'init') {
@@ -77,6 +52,8 @@ if (args[0] === 'daemon' || args[0] === 'init') {
     .help()
     .strict()
     .completion()
+    .command(require('./commands/daemon'))
+    .command(require('./commands/init'))
     .parse(args)
 } else {
   // here we have to make a separate yargs instance with
@@ -86,19 +63,61 @@ if (args[0] === 'daemon' || args[0] === 'init') {
     if (err) {
       throw err
     }
+
     utils.getIPFS(argv, (err, ipfs, cleanup) => {
-      if (err) { throw err }
+      if (err) {
+        throw err
+      }
+
+      // add mfs commands
+      mfs(cli)
+
+      // NOTE: This creates an alias of
+      // `jsipfs files {add, get, cat}` to `jsipfs {add, get, cat}`.
+      // This will stay until https://github.com/ipfs/specs/issues/98 is resolved.
+      const addCmd = require('./commands/files/add')
+      const catCmd = require('./commands/files/cat')
+      const getCmd = require('./commands/files/get')
+      const aliases = [addCmd, catCmd, getCmd]
+      aliases.forEach((alias) => {
+        cli.command(alias)
+      })
 
       cli
+        .commandDir('commands')
         .help()
         .strict()
         .completion()
-        .parse(args, { ipfs: ipfs }, (err, argv, output) => {
-          if (output) { print(output) }
 
-          cleanup(() => {
-            if (err) { throw err }
-          })
+      let exitCode = 0
+
+      const parser = new YargsPromise(cli, { ipfs })
+      parser.parse(args)
+        .then(({ data, argv }) => {
+          if (data) {
+            print(data)
+          }
+        })
+        .catch((arg) => {
+          debug(arg)
+
+          // the argument can have a different shape depending on where the error came from
+          if (arg.message) {
+            print(arg.message)
+          } else if (arg.error && arg.error.message) {
+            print(arg.error.message)
+          } else {
+            print('Unknown error, please re-run the command with DEBUG=ipfs:cli to see debug output')
+          }
+
+          exitCode = 1
+        })
+        .then(() => cleanup())
+        .catch(() => {})
+        .then(() => {
+          if (exitCode !== 0) {
+            process.exit(exitCode)
+          }
         })
     })
   })
diff --git a/src/cli/commands/files.js b/src/cli/commands/files.js
deleted file mode 100644
index 1e24b3c226..0000000000
--- a/src/cli/commands/files.js
+++ /dev/null
@@ -1,20 +0,0 @@
-'use strict'
-
-const print = require('../utils').print
-const lsCmd = require('./ls')
-
-module.exports = {
-  command: 'files <command>',
-
-  description: 'Operations over files (add, cat, get, ls, etc)',
-
-  builder (yargs) {
-    return yargs
-      .commandDir('files')
-      .command(lsCmd)
-  },
-
-  handler (argv) {
-    print('Type `jsipfs files --help` for more instructions')
-  }
-}
diff --git a/src/cli/commands/files/get.js b/src/cli/commands/files/get.js
index c177fb8719..d9e0a39a67 100644
--- a/src/cli/commands/files/get.js
+++ b/src/cli/commands/files/get.js
@@ -30,6 +30,7 @@ function fileHandler (dir) {
         callback(err)
       } else {
         const fullFilePath = path.join(dir, file.path)
+
         if (file.content) {
           file.content
             .pipe(fs.createWriteStream(fullFilePath))
diff --git a/src/cli/utils.js b/src/cli/utils.js
index f993e0caef..02f830f6c6 100644
--- a/src/cli/utils.js
+++ b/src/cli/utils.js
@@ -9,6 +9,7 @@ const log = debug('cli')
 log.error = debug('cli:error')
 const Progress = require('progress')
 const byteman = require('byteman')
+const promisify = require('promisify-es6')
 
 exports = module.exports
 
@@ -40,7 +41,7 @@ function getAPICtl (apiAddr) {
 
 exports.getIPFS = (argv, callback) => {
   if (argv.api || isDaemonOn()) {
-    return callback(null, getAPICtl(argv.api), (cb) => cb())
+    return callback(null, getAPICtl(argv.api), promisify((cb) => cb()))
   }
 
   // Required inline to reduce startup time
@@ -55,13 +56,13 @@ exports.getIPFS = (argv, callback) => {
     }
   })
 
-  const cleanup = (cb) => {
+  const cleanup = promisify((cb) => {
     if (node && node._repo && !node._repo.closed) {
-      node._repo.close(() => cb())
+      node._repo.close((err) => cb(err))
     } else {
       cb()
     }
-  }
+  })
 
   node.on('error', (err) => {
     throw err
diff --git a/src/core/components/index.js b/src/core/components/index.js
index 7221575007..9eb36ad4c3 100644
--- a/src/core/components/index.js
+++ b/src/core/components/index.js
@@ -26,3 +26,4 @@ exports.dht = require('./dht')
 exports.dns = require('./dns')
 exports.key = require('./key')
 exports.stats = require('./stats')
+exports.mfs = require('ipfs-mfs/core')
diff --git a/src/core/index.js b/src/core/index.js
index 1b561f96c6..3cc3517095 100644
--- a/src/core/index.js
+++ b/src/core/index.js
@@ -133,6 +133,13 @@ class IPFS extends EventEmitter {
       isIPFS: isIPFS
     }
 
+    // ipfs.files
+    const mfs = components.mfs(this)
+
+    Object.keys(mfs).forEach(key => {
+      this.files[key] = mfs[key]
+    })
+
     boot(this)
   }
 }
diff --git a/src/http/api/resources/files.js b/src/http/api/resources/files.js
index 1cd93e158e..a3b7e8eaed 100644
--- a/src/http/api/resources/files.js
+++ b/src/http/api/resources/files.js
@@ -34,7 +34,8 @@ exports.parseKey = (request, reply) => {
   if (!request.query.arg) {
     return reply({
       Message: "Argument 'key' is required",
-      Code: 0
+      Code: 0,
+      Type: 'error'
     }).code(400).takeover()
   }
 
@@ -54,7 +55,8 @@ exports.parseKey = (request, reply) => {
     log.error(err)
     return reply({
       Message: 'invalid ipfs ref path',
-      Code: 0
+      Code: 0,
+      Type: 'error'
     }).code(500).takeover()
   }
 
@@ -81,9 +83,9 @@ exports.cat = {
       if (err) {
         log.error(err)
         if (err.message === 'No such file') {
-          reply({Message: 'No such file'}).code(500)
+          reply({Message: 'No such file', Code: 0, Type: 'error'}).code(500)
         } else {
-          reply({Message: 'Failed to cat file: ' + err, Code: 0}).code(500)
+          reply({Message: 'Failed to cat file: ' + err, Code: 0, Type: 'error'}).code(500)
         }
         return
       }
@@ -177,7 +179,8 @@ exports.add = {
     if (!request.payload) {
       return reply({
         Message: 'Array, Buffer, or String is required.',
-        code: 0
+        Code: 0,
+        Type: 'error'
       }).code(400).takeover()
     }
 
@@ -211,7 +214,8 @@ exports.add = {
       if (!filesParsed) {
         return reply({
           Message: "File argument 'data' is required.",
-          code: 0
+          Code: 0,
+          Type: 'error'
         }).code(400).takeover()
       }
       fileAdder.end()
@@ -302,7 +306,8 @@ exports.immutableLs = {
       if (err) {
         return reply({
           Message: 'Failed to list dir: ' + err.message,
-          Code: 0
+          Code: 0,
+          Type: 'error'
         }).code(500).takeover()
       }
 
diff --git a/src/http/api/routes/files.js b/src/http/api/routes/files.js
index 2400f6012b..fc8222f180 100644
--- a/src/http/api/routes/files.js
+++ b/src/http/api/routes/files.js
@@ -1,6 +1,7 @@
 'use strict'
 
 const resources = require('./../resources')
+const mfs = require('ipfs-mfs/http')
 
 module.exports = (server) => {
   const api = server.select('API')
@@ -54,4 +55,6 @@ module.exports = (server) => {
       handler: resources.files.immutableLs.handler
     }
   })
+
+  mfs(api)
 }
diff --git a/src/http/error-handler.js b/src/http/error-handler.js
index 012a98f173..0c490d4639 100644
--- a/src/http/error-handler.js
+++ b/src/http/error-handler.js
@@ -14,9 +14,15 @@ module.exports = (api, server) => {
 
     let statusCode = 200
     let msg = 'Sorry, something went wrong, please retrace your steps.'
+    let code = 1
 
     if (res.isBoom) {
       statusCode = res.output.payload.statusCode
+      msg = res.output.payload.message
+
+      if (res.data && res.data.code !== undefined) {
+        code = res.data.code
+      }
 
       if (res.message && res.isDeveloperError) {
         msg = res.message.replace('Uncaught error: ', '')
@@ -36,7 +42,8 @@ module.exports = (api, server) => {
 
       reply({
         Message: msg,
-        Code: 1
+        Code: code,
+        Type: 'error'
       }).code(statusCode)
       return
     }
diff --git a/src/http/gateway/resources/gateway.js b/src/http/gateway/resources/gateway.js
index aef2451a33..c3a866c359 100644
--- a/src/http/gateway/resources/gateway.js
+++ b/src/http/gateway/resources/gateway.js
@@ -17,7 +17,8 @@ module.exports = {
     if (!request.params.cid) {
       return reply({
         Message: 'Path Resolve error: path must contain at least one component',
-        Code: 0
+        Code: 0,
+        Type: 'error'
       }).code(400).takeover()
     }
 
@@ -63,10 +64,10 @@ module.exports = {
             return reply(errorToString).code(404)
           case (errorToString.startsWith('Error: multihash length inconsistent')):
           case (errorToString.startsWith('Error: Non-base58 character')):
-            return reply({ Message: errorToString, code: 0 }).code(400)
+            return reply({ Message: errorToString, Code: 0, Type: 'error' }).code(400)
           default:
             log.error(err)
-            return reply({ Message: errorToString, code: 0 }).code(500)
+            return reply({ Message: errorToString, Code: 0, Type: 'error' }).code(500)
         }
       }
     }
diff --git a/test/browser.js b/test/browser.js
new file mode 100644
index 0000000000..4b41564257
--- /dev/null
+++ b/test/browser.js
@@ -0,0 +1,8 @@
+'use strict'
+
+const isWebWorker = require('detect-webworker')
+
+if (isWebWorker) {
+  // https://github.com/Joris-van-der-Wel/karma-mocha-webworker/issues/4
+  global.MFS_DISABLE_CONCURRENCY = true
+}
diff --git a/test/cli/commands.js b/test/cli/commands.js
index 7a8502bc4c..2c0c5fc033 100644
--- a/test/cli/commands.js
+++ b/test/cli/commands.js
@@ -4,7 +4,8 @@
 const expect = require('chai').expect
 const runOnAndOff = require('../utils/on-and-off')
 
-const commandCount = 78
+const commandCount = 77
+
 describe('commands', () => runOnAndOff((thing) => {
   let ipfs
 
diff --git a/test/cli/file.js b/test/cli/file.js
index e20a16101f..e4a5e0c9ce 100644
--- a/test/cli/file.js
+++ b/test/cli/file.js
@@ -12,7 +12,7 @@ describe('file ls', () => runOnAndOff((thing) => {
   before(function () {
     this.timeout(50 * 1000)
     ipfs = thing.ipfs
-    return ipfs('files add -r test/fixtures/test-data/recursive-get-dir')
+    return ipfs('add -r test/fixtures/test-data/recursive-get-dir')
   })
 
   it('prints a filename', () => {
diff --git a/test/cli/files.js b/test/cli/files.js
index 32fe28fc00..2f749f1cfe 100644
--- a/test/cli/files.js
+++ b/test/cli/files.js
@@ -126,7 +126,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add with progress', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add -p src/init-files/init-docs/readme')
+    return ipfs('add -p src/init-files/init-docs/readme')
       .then((out) => {
         expect(out)
           .to.eql('added QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB readme\n')
@@ -136,7 +136,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add src/init-files/init-docs/readme')
+    return ipfs('add src/init-files/init-docs/readme')
       .then((out) => {
         expect(out)
           .to.eql('added QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB readme\n')
@@ -156,7 +156,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add recursively test', function () {
     this.timeout(60 * 1000)
 
-    return ipfs('files add -r test/fixtures/test-data/recursive-get-dir')
+    return ipfs('add -r test/fixtures/test-data/recursive-get-dir')
       .then((out) => {
         expect(out).to.eql(recursiveGetDirResults.join('\n') + '\n')
       })
@@ -165,7 +165,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add directory with trailing slash test', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add -r test/fixtures/test-data/recursive-get-dir/')
+    return ipfs('add -r test/fixtures/test-data/recursive-get-dir/')
       .then((out) => {
         expect(out).to.eql(recursiveGetDirResults.join('\n') + '\n')
       })
@@ -179,7 +179,7 @@ describe('files', () => runOnAndOff((thing) => {
       'added QmXJGoo27bg7ExNAtr9vRcivxDwcfHtkxatGno9HrUdR16 odd-name-[v0]'
     ]
 
-    return ipfs('files add -r test/fixtures/odd-name-[v0]')
+    return ipfs('add -r test/fixtures/odd-name-[v0]')
       .then((out) => {
         expect(out).to.eql(expected.join('\n') + '\n')
       })
@@ -260,7 +260,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add --quiet', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add -q src/init-files/init-docs/readme')
+    return ipfs('add -q src/init-files/init-docs/readme')
       .then((out) => {
         expect(out)
           .to.eql('added QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB\n')
@@ -270,7 +270,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add --quieter', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add -Q -w test/fixtures/test-data/hello test/test-data/node.json')
+    return ipfs('add -Q -w test/fixtures/test-data/hello test/test-data/node.json')
       .then((out) => {
         expect(out)
           .to.eql('QmYRMUVULBfj7WrdPESnwnyZmtayN6Sdrwh1nKcQ9QgQeZ\n')
@@ -280,7 +280,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('add --silent', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files add --silent src/init-files/init-docs/readme')
+    return ipfs('add --silent src/init-files/init-docs/readme')
       .then((out) => {
         expect(out)
           .to.eql('')
@@ -288,7 +288,7 @@ describe('files', () => runOnAndOff((thing) => {
   })
 
   it('add --only-hash outputs correct hash', function () {
-    return ipfs('files add --only-hash src/init-files/init-docs/readme')
+    return ipfs('add --only-hash src/init-files/init-docs/readme')
       .then(out =>
         expect(out)
           .to.eql('added QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB readme\n')
@@ -302,7 +302,7 @@ describe('files', () => runOnAndOff((thing) => {
     const filepath = path.join(os.tmpdir(), `${content}.txt`)
     fs.writeFileSync(filepath, content)
 
-    return ipfs(`files add --only-hash ${filepath}`)
+    return ipfs(`add --only-hash ${filepath}`)
       .then(out => {
         const hash = out.split(' ')[1]
 
@@ -322,7 +322,7 @@ describe('files', () => runOnAndOff((thing) => {
     const content = String(Math.random())
     fs.writeFileSync(filePath, content)
 
-    return ipfs(`files add -Q ${filePath}`)
+    return ipfs(`add -Q ${filePath}`)
       .then(out => {
         const hash = out.trim()
         return ipfs(`pin ls ${hash}`)
@@ -337,7 +337,7 @@ describe('files', () => runOnAndOff((thing) => {
     const content = String(Math.random())
     fs.writeFileSync(filePath, content)
 
-    return ipfs(`files add -Q --pin=false ${filePath}`)
+    return ipfs(`add -Q --pin=false ${filePath}`)
       .then(out => ipfs.fail(`pin ls ${out.trim()}`))
       .then(() => clean(filePath))
   })
@@ -358,7 +358,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('cat', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB')
+    return ipfs('cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB')
       .then((out) => {
         expect(out).to.eql(readme)
       })
@@ -376,7 +376,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('cat part of a file using `count`', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB --offset 21 --count 5')
+    return ipfs('cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB --offset 21 --count 5')
       .then((out) => {
         expect(out).to.eql(readme.substring(21, 26))
       })
@@ -385,7 +385,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('cat part of a file using `length`', function () {
     this.timeout(30 * 1000)
 
-    return ipfs('files cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB --offset 21 --length 5')
+    return ipfs('cat QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB --offset 21 --length 5')
       .then((out) => {
         expect(out).to.eql(readme.substring(21, 26))
       })
@@ -402,7 +402,7 @@ describe('files', () => runOnAndOff((thing) => {
   it('get', function () {
     this.timeout(20 * 1000)
 
-    return ipfs('files get QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB')
+    return ipfs('get QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB')
       .then((out) => {
         expect(out)
           .to.eql('Saving file(s) QmPZ9gcCEpqKTo6aq61g2nXGUhM4iCL3ewB6LDXZCtioEB\n')
@@ -437,7 +437,7 @@ describe('files', () => runOnAndOff((thing) => {
     const outDir = path.join(process.cwd(), 'Qmaj2NmcyAXT8dFmZRRytE12wpcaHADzbChKToMEjBsj5Z')
     rimraf(outDir)
 
-    return ipfs('files get Qmaj2NmcyAXT8dFmZRRytE12wpcaHADzbChKToMEjBsj5Z')
+    return ipfs('get Qmaj2NmcyAXT8dFmZRRytE12wpcaHADzbChKToMEjBsj5Z')
       .then((out) => {
         expect(out).to.eql(
           'Saving file(s) Qmaj2NmcyAXT8dFmZRRytE12wpcaHADzbChKToMEjBsj5Z\n'
diff --git a/test/cli/init.js b/test/cli/init.js
index 86e0dbacda..b1a826c1db 100644
--- a/test/cli/init.js
+++ b/test/cli/init.js
@@ -42,7 +42,7 @@ describe('init', function () {
 
       // Test that the following was written when init-ing the repo
       // jsipfs files cat /ipfs/QmfGBRT6BbWJd7yUc2uYdaUZJBbnEFvTqehPFoSMQ6wgdr/readme
-      let command = out.substring(out.indexOf('files cat'), out.length - 2 /* omit the newline char */)
+      let command = out.substring(out.indexOf('cat'), out.length - 2 /* omit the newline char */)
       return ipfs(command)
     }).then((out) => expect(out).to.equal(readme))
   })
diff --git a/test/cli/ls.js b/test/cli/ls.js
index bd4ed58bfd..4eccf82c07 100644
--- a/test/cli/ls.js
+++ b/test/cli/ls.js
@@ -9,7 +9,7 @@ describe('ls', () => runOnAndOff((thing) => {
 
   before(() => {
     ipfs = thing.ipfs
-    return ipfs('files add -r test/fixtures/test-data/recursive-get-dir')
+    return ipfs('add -r test/fixtures/test-data/recursive-get-dir')
   })
 
   it('prints added files', function () {
diff --git a/test/cli/pin.js b/test/cli/pin.js
index f6c77eb67a..1795f9a640 100644
--- a/test/cli/pin.js
+++ b/test/cli/pin.js
@@ -24,7 +24,7 @@ describe('pin', () => runOnAndOff(thing => {
   before(function () {
     this.timeout(15 * 1000)
     ipfs = thing.ipfs
-    return ipfs(`files add -r ${fixturePath}`)
+    return ipfs(`add -r ${fixturePath}`)
   })
 
   describe('rm', function () {
diff --git a/test/core/interface.spec.js b/test/core/interface.spec.js
index 977a379441..7daf289e26 100644
--- a/test/core/interface.spec.js
+++ b/test/core/interface.spec.js
@@ -29,54 +29,7 @@ describe('interface-ipfs-core tests', () => {
     skip: { reason: 'TODO: DHT is not implemented in js-ipfs yet!' }
   })
 
-  tests.files(defaultCommonFactory, {
-    skip: [
-      {
-        name: 'cp',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'mkdir',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'stat',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'rm',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'read',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'readReadableStream',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'readPullStream',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'write',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'mv',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'flush',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'ls',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      }
-    ]
-  })
+  tests.files(defaultCommonFactory)
 
   tests.key(CommonFactory.create({
     spawnOptions: {
diff --git a/test/http-api/files.js b/test/http-api/files.js
index 7e85697299..01839f49e1 100644
--- a/test/http-api/files.js
+++ b/test/http-api/files.js
@@ -7,6 +7,9 @@ const dirtyChai = require('dirty-chai')
 const DaemonFactory = require('ipfsd-ctl')
 const expect = chai.expect
 chai.use(dirtyChai)
+const {
+  FILE_TYPES
+} = require('ipfs-mfs')
 
 const df = DaemonFactory.create({ exec: 'src/cli/bin.js' })
 
@@ -46,4 +49,356 @@ describe('.files', () => {
         })
     })
   })
+
+  describe('.ls', function () {
+    it('lists empty directory', () => {
+      return ipfs.files.ls()
+        .then(files => {
+          expect(files).to.be.empty()
+        })
+    })
+
+    it('lists files', () => {
+      const fileName = `single-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${fileName}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.ls())
+        .then(files => {
+          expect(files.length).to.equal(1)
+          expect(files[0].name).to.equal(fileName)
+        })
+    })
+
+    it('lists files in directories', () => {
+      const dirName = `dir-${Math.random()}`
+      const fileName = `file-in-dir-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${dirName}/${fileName}`, Buffer.from('Hello world'), {
+        create: true,
+        parents: true
+      })
+        .then(() => ipfs.files.ls(`/${dirName}`))
+        .then(files => {
+          expect(files.length).to.equal(1)
+          expect(files[0].name).to.equal(fileName)
+        })
+    })
+  })
+
+  describe('.cp', function () {
+    it('copies a file', () => {
+      const source = `source-file-${Math.random()}.txt`
+      const destination = `destination-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${source}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.cp(`/${source}`, `/${destination}`))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceFile = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceFile.type).to.equal(FILE_TYPES.file)
+
+          const destFile = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destFile.type).to.equal(FILE_TYPES.file)
+        })
+    })
+
+    it('copies a directory', () => {
+      const source = `source-dir-${Math.random()}`
+      const destination = `destination-dir-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${source}`)
+        .then(() => ipfs.files.cp(`/${source}`, `/${destination}`))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceDir = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceDir.type).to.equal(FILE_TYPES.directory)
+
+          const destDir = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destDir.type).to.equal(FILE_TYPES.directory)
+        })
+    })
+
+    it('copies a file with array args', () => {
+      const source = `source-file-${Math.random()}.txt`
+      const destination = `destination-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${source}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.cp([`/${source}`, `/${destination}`]))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceFile = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceFile.type).to.equal(FILE_TYPES.file)
+
+          const destFile = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destFile.type).to.equal(FILE_TYPES.file)
+        })
+    })
+
+    it('copies a directory with array args', () => {
+      const source = `source-dir-${Math.random()}`
+      const destination = `destination-dir-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${source}`)
+        .then(() => ipfs.files.cp([`/${source}`, `/${destination}`]))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceDir = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceDir.type).to.equal(FILE_TYPES.directory)
+
+          const destDir = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destDir.type).to.equal(FILE_TYPES.directory)
+        })
+    })
+  })
+
+  describe('.mkdir', function () {
+    it('makes a directory', () => {
+      const directory = `directory-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${directory}`)
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const dir = files
+            .filter(file => file.name === directory)
+            .pop()
+
+          expect(dir.type).to.equal(FILE_TYPES.directory)
+        })
+    })
+  })
+
+  describe('.mv', function () {
+    it('moves a file', () => {
+      const source = `source-file-${Math.random()}.txt`
+      const destination = `destination-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${source}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.mv(`/${source}`, `/${destination}`))
+        .then(() => ipfs.files.ls(`/`))
+        .then(files => {
+          const sourceFile = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceFile).to.not.exist()
+
+          const destFile = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destFile.type).to.equal(FILE_TYPES.file)
+        })
+    })
+
+    it('moves a directory', () => {
+      const source = `source-dir-${Math.random()}`
+      const destination = `destination-dir-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${source}`)
+        .then(() => ipfs.files.mv(`/${source}`, `/${destination}`))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceDir = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceDir).to.not.exist()
+
+          const destDir = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destDir.type).to.equal(FILE_TYPES.directory)
+        })
+    })
+
+    it('moves a file with array args', () => {
+      const source = `source-file-${Math.random()}.txt`
+      const destination = `destination-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${source}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.mv([`/${source}`, `/${destination}`]))
+        .then(() => ipfs.files.ls(`/`))
+        .then(files => {
+          const sourceFile = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceFile).to.not.exist()
+
+          const destFile = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destFile.type).to.equal(FILE_TYPES.file)
+        })
+    })
+
+    it('moves a directory with array args', () => {
+      const source = `source-dir-${Math.random()}`
+      const destination = `destination-dir-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${source}`)
+        .then(() => ipfs.files.mv([`/${source}`, `/${destination}`]))
+        .then(() => ipfs.files.ls(`/`, {
+          long: true
+        }))
+        .then(files => {
+          const sourceDir = files
+            .filter(file => file.name === source)
+            .pop()
+
+          expect(sourceDir).to.not.exist()
+
+          const destDir = files
+            .filter(file => file.name === destination)
+            .pop()
+
+          expect(destDir.type).to.equal(FILE_TYPES.directory)
+        })
+    })
+  })
+
+  describe('.read', function () {
+    it('reads a file', () => {
+      const fileName = `single-file-${Math.random()}.txt`
+      const content = Buffer.from('Hello world')
+
+      return ipfs.files.write(`/${fileName}`, content, {
+        create: true
+      })
+        .then(() => ipfs.files.read(`/${fileName}`))
+        .then(buffer => {
+          expect(buffer).to.deep.equal(content)
+        })
+    })
+  })
+
+  describe('.rm', function () {
+    it('removes a file', () => {
+      const fileName = `single-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${fileName}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.rm(`/${fileName}`))
+        .then(() => ipfs.files.ls(`/`))
+        .then(files => {
+          const file = files
+            .filter(file => file.name === fileName)
+            .pop()
+
+          expect(file).to.not.exist()
+        })
+    })
+
+    it('removes a directory', () => {
+      const dirName = `dir-${Math.random()}`
+      const fileName = `file-in-dir-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${dirName}/${fileName}`, Buffer.from('Hello world'), {
+        create: true,
+        parents: true
+      })
+        .then(() => ipfs.files.rm(`/${dirName}`, {
+          recursive: true
+        }))
+        .then(() => ipfs.files.ls(`/`))
+        .then(files => {
+          const dir = files
+            .filter(file => file.name === dirName)
+            .pop()
+
+          expect(dir).to.not.exist()
+        })
+    })
+  })
+
+  describe('.stat', function () {
+    it('stats a file', () => {
+      const fileName = `single-file-${Math.random()}.txt`
+
+      return ipfs.files.write(`/${fileName}`, Buffer.from('Hello world'), {
+        create: true
+      })
+        .then(() => ipfs.files.stat(`/${fileName}`))
+        .then(stats => {
+          expect(stats).to.deep.equal({
+            blocks: 1,
+            cumulativeSize: 69,
+            hash: 'Qmetpc7cZmN25Wcc6R27cGCAvCDqCS5GjHG4v7xABEfpmJ',
+            local: undefined,
+            size: 11,
+            sizeLocal: undefined,
+            type: 'file',
+            withLocality: false
+          })
+        })
+    })
+
+    it('stats a directory', () => {
+      const dirName = `dir-${Math.random()}`
+
+      return ipfs.files.mkdir(`/${dirName}`)
+        .then(() => ipfs.files.stat(`/${dirName}`))
+        .then(stats => {
+          expect(stats).to.deep.equal({
+            blocks: 0,
+            cumulativeSize: 4,
+            hash: 'QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn',
+            local: undefined,
+            size: 0,
+            sizeLocal: undefined,
+            type: 'directory',
+            withLocality: false
+          })
+        })
+    })
+  })
 })
diff --git a/test/http-api/index.js b/test/http-api/index.js
index d619014896..901cb212ef 100644
--- a/test/http-api/index.js
+++ b/test/http-api/index.js
@@ -9,3 +9,4 @@ require('./inject')
 require('./interface')
 require('./object')
 require('./version')
+require('./files')
diff --git a/test/http-api/interface.js b/test/http-api/interface.js
index 1f2955377b..e123093687 100644
--- a/test/http-api/interface.js
+++ b/test/http-api/interface.js
@@ -25,54 +25,7 @@ describe('interface-ipfs-core over ipfs-api tests', () => {
     skip: { reason: 'TODO: DHT is not implemented in js-ipfs yet!' }
   })
 
-  tests.files(defaultCommonFactory, {
-    skip: [
-      {
-        name: 'cp',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'mkdir',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'stat',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'rm',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'read',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'readReadableStream',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'readPullStream',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'write',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'mv',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'flush',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      },
-      {
-        name: 'ls',
-        reason: 'TODO: MFS is not implemented in js-ipfs yet!'
-      }
-    ]
-  })
+  tests.files(defaultCommonFactory)
 
   tests.key(CommonFactory.create({
     spawnOptions: {
diff --git a/test/utils/ipfs-exec.js b/test/utils/ipfs-exec.js
index 38742b76b5..786a3f7f3b 100644
--- a/test/utils/ipfs-exec.js
+++ b/test/utils/ipfs-exec.js
@@ -13,7 +13,7 @@ const _ = require('lodash')
 // The top level export is a function that can be passed a `repoPath`
 // and optional `opts` to customize the execution of the commands.
 // This function returns the actual executer, which consists of
-// `ipfs('files get <hash>')` and `ipfs.fail('files get <hash>')`
+// `ipfs('get <hash>')` and `ipfs.fail('files get <hash>')`
 // The first one executes and asserts that the command ran successfully
 // and returns a promise which is resolved to `stdout` of the command.
 // The `.fail` variation asserts that the command exited with `Code > 0`