diff --git a/.travis.yml b/.travis.yml
index 969f268..fa3917b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ sudo: false
 node_js:
   - "0.10"
   - "0.12"
+  - "4.2"
   - "4"
 
 notifications:
@@ -22,7 +23,6 @@ script:
 after_success:
   - npm install coveralls
   - cat coverage/lcov.info | coveralls
-  - mv coverage/lcov.info .
 
 matrix:
   allow_failures:
diff --git a/index.js b/index.js
index e691d24..6ce116d 100644
--- a/index.js
+++ b/index.js
@@ -7,29 +7,26 @@
 
 'use strict'
 
-var letta = require('letta')
-var isError = require('is-typeof-error')
-var isNodeStream = require('is-node-stream')
-var isChildProcess = require('is-child-process')
+var utils = require('./utils')
 
 module.exports = function lettaValue (val) {
-  if (isNodeStream(val) || isChildProcess(val)) {
-    return letta(require('on-stream-end'), require('stream-exhaust')(val))
+  if (utils.isNodeStream(val) || utils.isChildProcess(val)) {
+    return utils.letta(utils.onStreamEnd, utils.streamExhaust(val))
   }
   if (val && typeof val.subscribe === 'function') {
     if (val.value) {
-      return letta(function () {
+      return utils.letta(function () {
         return val.value
       })
     }
-    return letta(subscribe, val)
+    return utils.letta(subscribe, val)
   }
-  if (isError(val)) {
-    return letta(function () {
+  if (utils.isTypeofError(val)) {
+    return utils.letta(function () {
       throw val
     })
   }
-  return letta(function () {
+  return utils.letta(function () {
     return val
   })
 }
@@ -40,6 +37,6 @@ module.exports = function lettaValue (val) {
 
 function subscribe (val, callback) {
   val.subscribe(function noop () {}, callback, function onComplete () {
-    callback.apply(this, [null].concat(require('sliced')(arguments)))
+    callback.apply(this, [null].concat(utils.sliced(arguments)))
   }.bind(this))
 }
diff --git a/package.json b/package.json
index 94de950..89bc6f3 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,8 @@
     "is-child-process": "^1.0.0",
     "is-node-stream": "^1.0.0",
     "is-typeof-error": "^1.0.1",
-    "letta": "^0.2.0",
+    "lazy-cache": "^0.2.3",
+    "letta": "*",
     "on-stream-end": "^1.0.0",
     "sliced": "^1.0.1",
     "stream-exhaust": "^1.0.1"
@@ -60,4 +61,4 @@
     "thunkgs",
     "yield"
   ]
-}
\ No newline at end of file
+}
diff --git a/utils.js b/utils.js
new file mode 100644
index 0000000..db0d228
--- /dev/null
+++ b/utils.js
@@ -0,0 +1,28 @@
+/* jshint asi:true */
+
+'use strict'
+
+/**
+ * Lazily required module dependencies
+ */
+
+var utils = require('lazy-cache')(require) // eslint-disable-line no-undef, no-native-reassign
+var fn = require
+
+require = utils // eslint-disable-line no-undef, no-native-reassign
+
+require('is-child-process')
+require('is-node-stream')
+require('is-typeof-error')
+require('letta')
+require('on-stream-end')
+require('sliced')
+require('stream-exhaust')
+
+require = fn // eslint-disable-line no-undef, no-native-reassign
+
+/**
+ * Expose `utils` modules
+ */
+
+module.exports = utils