diff --git a/package.json b/package.json
index bfc80c569..1fea1500e 100644
--- a/package.json
+++ b/package.json
@@ -108,7 +108,7 @@
     "browser-process-platform": "~0.1.1",
     "cross-env": "^6.0.0",
     "go-ipfs-dep": "^0.4.22",
-    "interface-ipfs-core": "^0.119.0",
+    "interface-ipfs-core": "github:ipfs/interface-js-ipfs-core#fix/files-tests-tweaks",
     "ipfsd-ctl": "^0.47.1",
     "nock": "^11.4.0",
     "stream-equal": "^1.1.1"
diff --git a/src/files/cp.js b/src/files/cp.js
index de4e0954d..b779301a2 100644
--- a/src/files/cp.js
+++ b/src/files/cp.js
@@ -1,20 +1,24 @@
 'use strict'
 
-const promisify = require('promisify-es6')
-const findSources = require('../utils/find-sources')
+const configure = require('../lib/configure')
+const { findSources } = require('./utils')
 
-module.exports = (send) => {
-  return promisify(function () {
-    const {
-      callback,
-      sources,
-      opts
-    } = findSources(Array.prototype.slice.call(arguments))
+module.exports = configure(({ ky }) => {
+  return (...args) => {
+    const { sources, options } = findSources(args)
 
-    send({
-      path: 'files/cp',
-      args: sources,
-      qs: opts
-    }, (error) => callback(error))
-  })
-}
+    const searchParams = new URLSearchParams(options.searchParams)
+    sources.forEach(src => searchParams.append('arg', src))
+    if (options.format) searchParams.set('format', options.format)
+    if (options.flush != null) searchParams.set('flush', options.flush)
+    if (options.hashAlg) searchParams.set('hash', options.hashAlg)
+    if (options.parents != null) searchParams.set('parents', options.parents)
+
+    return ky.post('files/cp', {
+      timeout: options.timeout,
+      signal: options.signal,
+      headers: options.headers,
+      searchParams
+    }).text()
+  }
+})
diff --git a/src/files/flush.js b/src/files/flush.js
index 6a131989b..b66568353 100644
--- a/src/files/flush.js
+++ b/src/files/flush.js
@@ -1,17 +1,27 @@
 'use strict'
 
-const promisify = require('promisify-es6')
+const CID = require('cids')
+const configure = require('../lib/configure')
 
-module.exports = (send) => {
-  return promisify((args, callback) => {
-    if (typeof args === 'function') {
-      callback = args
-      args = '/'
+module.exports = configure(({ ky }) => {
+  return async (path, options) => {
+    if (typeof path !== 'string') {
+      options = path
+      path = '/'
     }
 
-    return send({
-      path: 'files/flush',
-      args: args
-    }, (error) => callback(error))
-  })
-}
+    options = options || {}
+
+    const searchParams = new URLSearchParams(options.searchParams)
+    searchParams.set('arg', path)
+
+    const { Cid } = await ky.post('files/flush', {
+      timeout: options.timeout,
+      signal: options.signal,
+      headers: options.headers,
+      searchParams
+    }).json()
+
+    return new CID(Cid)
+  }
+})
diff --git a/src/files/index.js b/src/files/index.js
index c543d9b1e..6c86c589a 100644
--- a/src/files/index.js
+++ b/src/files/index.js
@@ -1,20 +1,22 @@
 'use strict'
 
 const callbackify = require('callbackify')
+const { collectify, streamify, pullify } = require('../lib/converters')
 const moduleConfig = require('../utils/module-config')
 
 module.exports = (arg, config) => {
   const send = moduleConfig(arg)
+  const ls = require('./ls')(config)
 
   return {
-    cp: require('./cp')(send),
-    mkdir: require('./mkdir')(send),
-    flush: require('./flush')(send),
+    cp: callbackify.variadic(require('./cp')(config)),
+    mkdir: callbackify.variadic(require('./mkdir')(config)),
+    flush: callbackify.variadic(require('./flush')(config)),
     stat: require('./stat')(send),
     rm: require('./rm')(send),
-    ls: require('./ls')(send),
-    lsReadableStream: require('./ls-readable-stream')(send),
-    lsPullStream: require('./ls-pull-stream')(send),
+    ls: callbackify.variadic(collectify(ls)),
+    lsReadableStream: streamify.readable(ls),
+    lsPullStream: pullify.source(ls),
     read: require('./read')(send),
     readReadableStream: require('./read-readable-stream')(send),
     readPullStream: require('./read-pull-stream')(send),
diff --git a/src/files/ls-pull-stream.js b/src/files/ls-pull-stream.js
deleted file mode 100644
index 111eba7ed..000000000
--- a/src/files/ls-pull-stream.js
+++ /dev/null
@@ -1,12 +0,0 @@
-'use strict'
-
-const toPull = require('stream-to-pull-stream')
-const lsReadableStream = require('./ls-readable-stream')
-
-module.exports = (send) => {
-  return (args, opts) => {
-    opts = opts || {}
-
-    return toPull.source(lsReadableStream(send)(args, opts))
-  }
-}
diff --git a/src/files/ls-readable-stream.js b/src/files/ls-readable-stream.js
deleted file mode 100644
index 404893e70..000000000
--- a/src/files/ls-readable-stream.js
+++ /dev/null
@@ -1,62 +0,0 @@
-'use strict'
-
-const {
-  Transform,
-  PassThrough
-} = require('readable-stream')
-const pump = require('pump')
-const ndjson = require('ndjson')
-const isStream = require('is-stream')
-
-const toEntry = (entry) => {
-  return {
-    name: entry.Name,
-    type: entry.Type,
-    size: entry.Size,
-    hash: entry.Hash
-  }
-}
-
-module.exports = (send) => {
-  return (args, opts) => {
-    opts = opts || {}
-
-    const transform = new Transform({
-      objectMode: true,
-
-      transform (entry, encoding, callback) {
-        callback(null, toEntry(entry))
-      }
-    })
-
-    const output = new PassThrough({
-      objectMode: true
-    })
-
-    send({
-      path: 'files/ls',
-      args: args,
-      qs: Object.assign({}, opts, { stream: true })
-    }, (err, res) => {
-      if (err) {
-        return output.destroy(err)
-      }
-
-      if (isStream(res)) {
-        const parse = ndjson.parse()
-
-        pump(res, parse, transform, output)
-      } else {
-        const entries = res.Entries || []
-
-        entries.forEach((entry) => {
-          output.write(toEntry(entry))
-        })
-
-        output.end()
-      }
-    })
-
-    return output
-  }
-}
diff --git a/src/files/ls.js b/src/files/ls.js
index ff22f5396..a36200d1d 100644
--- a/src/files/ls.js
+++ b/src/files/ls.js
@@ -1,37 +1,36 @@
 'use strict'
 
-const promisify = require('promisify-es6')
+const ndjson = require('iterable-ndjson')
+const toIterable = require('../lib/stream-to-iterable')
+const configure = require('../lib/configure')
+const toCamel = require('../lib/object-to-camel')
 
-const transform = function (res, callback) {
-  const entries = res.Entries || []
+module.exports = configure(({ ky }) => {
+  return async function * ls (path, options) {
+    options = options || {}
 
-  callback(null, entries.map((entry) => {
-    return {
-      name: entry.Name,
-      type: entry.Type,
-      size: entry.Size,
-      hash: entry.Hash
-    }
-  }))
-}
+    const searchParams = new URLSearchParams(options.searchParams)
+    searchParams.set('arg', `${path}`)
+    searchParams.set('stream', true)
+    if (options.cidBase) searchParams.set('cid-base', options.cidBase)
+    if (options.long != null) searchParams.set('long', options.long)
 
-module.exports = (send) => {
-  return promisify((args, opts, callback) => {
-    if (typeof (opts) === 'function') {
-      callback = opts
-      opts = {}
-    }
+    const res = await ky.post('files/ls', {
+      timeout: options.timeout,
+      signal: options.signal,
+      headers: options.headers,
+      searchParams
+    })
 
-    if (typeof (args) === 'function') {
-      callback = args
-      opts = {}
-      args = null
+    for await (const result of ndjson(toIterable(res.body))) {
+      // go-ipfs does not yet support the "stream" option
+      if ('Entries' in result) {
+        for (const entry of result.Entries || []) {
+          yield toCamel(entry)
+        }
+        return
+      }
+      yield toCamel(result)
     }
-
-    return send.andTransform({
-      path: 'files/ls',
-      args: args,
-      qs: opts
-    }, transform, callback)
-  })
-}
+  }
+})
diff --git a/src/files/mkdir.js b/src/files/mkdir.js
index b77fbf6dd..0fc3c238d 100644
--- a/src/files/mkdir.js
+++ b/src/files/mkdir.js
@@ -1,18 +1,24 @@
-
 'use strict'
 
-const promisify = require('promisify-es6')
+const configure = require('../lib/configure')
+
+module.exports = configure(({ ky }) => {
+  return (path, options) => {
+    options = options || {}
+
+    const searchParams = new URLSearchParams(options.searchParams)
+    searchParams.append('arg', path)
+    if (options.cidVersion != null) searchParams.set('cid-version', options.cidVersion)
+    if (options.format) searchParams.set('format', options.format)
+    if (options.flush != null) searchParams.set('flush', options.flush)
+    if (options.hashAlg) searchParams.set('hash', options.hashAlg)
+    if (options.parents != null) searchParams.set('parents', options.parents)
 
-module.exports = (send) => {
-  return promisify((args, opts, callback) => {
-    if (typeof (opts) === 'function') {
-      callback = opts
-      opts = {}
-    }
-    send({
-      path: 'files/mkdir',
-      args: args,
-      qs: opts
-    }, (error) => callback(error))
-  })
-}
+    return ky.post('files/mkdir', {
+      timeout: options.timeout,
+      signal: options.signal,
+      headers: options.headers,
+      searchParams
+    }).text()
+  }
+})
diff --git a/src/files/mv.js b/src/files/mv.js
index 234491b28..8546d8ab2 100644
--- a/src/files/mv.js
+++ b/src/files/mv.js
@@ -1,20 +1,24 @@
 'use strict'
 
-const promisify = require('promisify-es6')
-const findSources = require('../utils/find-sources')
+const configure = require('../lib/configure')
+const { findSources } = require('./utils')
 
-module.exports = (send) => {
-  return promisify(function () {
-    const {
-      callback,
-      sources,
-      opts
-    } = findSources(Array.prototype.slice.call(arguments))
+module.exports = configure(({ ky }) => {
+  return (...args) => {
+    const { sources, options } = findSources(args)
 
-    send({
-      path: 'files/mv',
-      args: sources,
-      qs: opts
-    }, (error) => callback(error))
-  })
-}
+    const searchParams = new URLSearchParams(options.searchParams)
+    sources.forEach(src => searchParams.append('arg', src))
+    if (options.format) searchParams.set('format', options.format)
+    if (options.flush != null) searchParams.set('flush', options.flush)
+    if (options.hashAlg) searchParams.set('hash', options.hashAlg)
+    if (options.parents != null) searchParams.set('parents', options.parents)
+
+    return ky.post('files/mv', {
+      timeout: options.timeout,
+      signal: options.signal,
+      headers: options.headers,
+      searchParams
+    }).text()
+  }
+})
diff --git a/src/files/utils.js b/src/files/utils.js
new file mode 100644
index 000000000..67a04eb6e
--- /dev/null
+++ b/src/files/utils.js
@@ -0,0 +1,23 @@
+'use strict'
+
+exports.findSources = (args) => {
+  let options = {}
+  let sources = []
+
+  if (!Array.isArray(args[args.length - 1]) && typeof args[args.length - 1] === 'object') {
+    options = args.pop()
+  }
+
+  if (args.length === 1 && Array.isArray(args[0])) {
+    // support ipfs.file.cp([src, dest], opts)
+    sources = args[0]
+  } else {
+    // support ipfs.file.cp(src, dest, opts) and ipfs.file.cp(src1, src2, dest, opts)
+    sources = args
+  }
+
+  return {
+    sources,
+    options
+  }
+}