diff --git a/lib/image/jpeg.coffee b/lib/image/jpeg.coffee
index 8bb96f2..8894be6 100644
--- a/lib/image/jpeg.coffee
+++ b/lib/image/jpeg.coffee
@@ -1,6 +1,6 @@
 fs = require 'fs'
 Data = '../data'
-setImmediate = setImmediate ? process.nextTick # backfill for node <0.10
+setImmediate = global.setImmediate ? process.nextTick # backfill for node <0.10
 
 class JPEG
     constructor: (@data) ->
diff --git a/lib/image/png.coffee b/lib/image/png.coffee
index fb7d794..5d1eaba 100644
--- a/lib/image/png.coffee
+++ b/lib/image/png.coffee
@@ -1,6 +1,6 @@
 zlib = require 'zlib'
 PNG = require 'png-js'
-setImmediate = setImmediate ? process.nextTick # backfill for node <0.10
+setImmediate = global.setImmediate ? process.nextTick # backfill for node <0.10
 
 class PNGImage
     constructor: (data) ->
diff --git a/lib/reference.coffee b/lib/reference.coffee
index a6fbed3..31a9921 100644
--- a/lib/reference.coffee
+++ b/lib/reference.coffee
@@ -4,7 +4,7 @@ By Devon Govett
 ###
 
 zlib = require 'zlib'
-setImmediate = setImmediate ? process.nextTick # backfill for node <0.10
+setImmediate = global.setImmediate ? process.nextTick # backfill for node <0.10
 
 class PDFReference
     constructor: (@id, @data = {}) ->