diff --git a/debug.js.map b/debug.js.map
index 468d250..c47794b 100644
--- a/debug.js.map
+++ b/debug.js.map
@@ -1 +1 @@
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\ No newline at end of file
+{"version":3,"sources":["debug.js"],"names":[],"mappings":";;;;;;AAAA;;;;;;kBAEe;MAAC,6DAAK;SAAiB,0CAAyB,IAAzB;CAAvB","file":"debug.js","sourcesContent":["import debug from 'debug';\n\nexport default (name='time-stamp') => debug(`loopback:mixins:${name}`);\n"],"sourceRoot":"/Users/clarkbw/src/pi/loopback-ds-timestamp-mixin/es6"}
\ No newline at end of file
diff --git a/index.js.map b/index.js.map
index 6ef1e31..92629a2 100644
--- a/index.js.map
+++ b/index.js.map
@@ -1 +1 @@
-{"version":3,"sources":["index.js"],"names":[],"mappings":";;;;;;;;;;;;;;kBAGe,qBAAU,UAAC,GAAD,EAAS;AAChC,MAAI,QAAJ,CAAa,YAAb,CAA0B,MAA1B,CAAiC,MAAjC,CAAwC,WAAxC,uBADgC;CAAT,EAEtB,uGAFY;;;AAIf,OAAO,OAAP,GAAiB,QAAQ,OAAR","file":"index.js","sourcesContent":["import { deprecate } from 'util';\nimport timestamp from './time-stamp';\n\nexport default deprecate((app) => {\n  app.loopback.modelBuilder.mixins.define('TimeStamp', timestamp);\n}, 'DEPRECATED: Use mixinSources, see https://github.com/clarkbw/loopback-ds-timestamp-mixin#mixinsources');\n\nmodule.exports = exports.default;\n"],"sourceRoot":"/Users/clarkbw/src/pi/loopback-ds-timestamp-mixin/es6"}
\ No newline at end of file
+{"version":3,"sources":["index.js"],"names":[],"mappings":";;;;;;AAAA;;AACA;;;;;;kBAEe,qBAAU,UAAC,GAAD,EAAS;AAChC,MAAI,QAAJ,CAAa,YAAb,CAA0B,MAA1B,CAAiC,MAAjC,CAAwC,WAAxC,uBADgC;CAAT,EAEtB,uGAFY;;;AAIf,OAAO,OAAP,GAAiB,QAAQ,OAAR","file":"index.js","sourcesContent":["import { deprecate } from 'util';\nimport timestamp from './time-stamp';\n\nexport default deprecate((app) => {\n  app.loopback.modelBuilder.mixins.define('TimeStamp', timestamp);\n}, 'DEPRECATED: Use mixinSources, see https://github.com/clarkbw/loopback-ds-timestamp-mixin#mixinsources');\n\nmodule.exports = exports.default;\n"],"sourceRoot":"/Users/clarkbw/src/pi/loopback-ds-timestamp-mixin/es6"}
\ No newline at end of file
diff --git a/package.json b/package.json
index 31109aa..8548003 100644
--- a/package.json
+++ b/package.json
@@ -42,6 +42,7 @@
     "babel-core": "latest",
     "babel-plugin-transform-es2015-modules-commonjs": "^6.3.16",
     "babel-plugin-transform-object-assign": "latest",
+    "babel-preset-es2015": "latest",
     "coveralls": "latest",
     "gulp": "latest",
     "gulp-babel": "latest",
diff --git a/time-stamp.js.map b/time-stamp.js.map
index 3cc9498..7557496 100644
--- a/time-stamp.js.map
+++ b/time-stamp.js.map
@@ -1 +1 @@
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\ No newline at end of file
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\ No newline at end of file