diff --git a/lib/process/debug-message.js b/lib/process/debug-message.js
index 9d8fbee..481134a 100644
--- a/lib/process/debug-message.js
+++ b/lib/process/debug-message.js
@@ -1,7 +1,7 @@
 'use strict';
 
-const PACKAGE_NAME = require('../../package.json').name,
-      PADDING      = (new Array(11)).join(' ');
+var PACKAGE_NAME = require('../../package.json').name,
+    PADDING      = (new Array(11)).join(' ');
 
 /**
  * Format a debug message
diff --git a/lib/process/decode-sources-with.js b/lib/process/decode-sources-with.js
index 6ed0cb8..15ea0a9 100644
--- a/lib/process/decode-sources-with.js
+++ b/lib/process/decode-sources-with.js
@@ -1,7 +1,5 @@
 'use strict';
 
-var fs = require('fs');
-
 var getFieldAsFn = require('./get-field-as-fn');
 
 /**
@@ -46,11 +44,7 @@ function decodeSourcesWith(codecs, mustDecode) {
         }
         // non-string implies error
         if (typeof decoded !== 'string') {
-          return getNamedError('Decoder returned a truthy value but it is not a string file path:\n' + decoded);
-        }
-        // non-existant file implies error
-        else if (!fs.existsSync(decoded) || !fs.statSync(decoded).isFile()) {
-          return getNamedError('Cannot find file at absolute path:\n' + decoded);
+          return getNamedError('Decoder returned a truthy value but it is not a string:\n' + decoded);
         }
         // otherwise success
         else {
diff --git a/lib/process/index.js b/lib/process/index.js
index 295ebe5..6c90de2 100644
--- a/lib/process/index.js
+++ b/lib/process/index.js
@@ -12,7 +12,7 @@ var debugMessage      = require('./debug-message'),
     encodeSourcesWith = require('./encode-sources-with'),
     testCodec         = require('./test-codec');
 
-const CODECS = require('../../codec');
+var CODECS = require('../../codec');
 
 /**
  * Process the given source-map per the given options.
diff --git a/package.json b/package.json
index 78b35d3..62cd878 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "adjust-sourcemap-loader",
-  "version": "1.2.0",
+  "version": "2.0.0-alpha.1",
   "description": "Webpack loader that adjusts source maps",
   "main": "index.js",
   "repository": {