diff --git a/index.js b/index.js
index 242da55..1a7476d 100644
--- a/index.js
+++ b/index.js
@@ -22,12 +22,12 @@ var filesLoadedBeforeTrace = Object.keys(require.cache);
 // patched before any user-land modules get loaded.
 require('continuation-local-storage');
 
-var SpanData = require('./lib/span-data.js');
-var Logger = require('./lib/logger.js');
+var SpanData = require('./src/span-data.js');
+var Logger = require('./src/logger.js');
 var semver = require('semver');
-var constants = require('./lib/constants.js');
+var constants = require('./src/constants.js');
 var path = require('path');
-var util = require('./lib/util.js');
+var util = require('./src/util.js');
 
 var modulesLoadedBeforeTrace = [];
 
@@ -152,7 +152,7 @@ var publicAgent = {
         JSON.stringify(modulesLoadedBeforeTrace));
     }
 
-    agent = require('./lib/trace-agent.js').get(config, logger);
+    agent = require('./src/trace-agent.js').get(config, logger);
     return this; // for chaining
   },
 
diff --git a/lib/.jshintrc b/src/.jshintrc
similarity index 100%
rename from lib/.jshintrc
rename to src/.jshintrc
diff --git a/lib/cls.js b/src/cls.js
similarity index 100%
rename from lib/cls.js
rename to src/cls.js
diff --git a/lib/constants.js b/src/constants.js
similarity index 100%
rename from lib/constants.js
rename to src/constants.js
diff --git a/lib/hooks/core/hook-http.js b/src/hooks/core/hook-http.js
similarity index 100%
rename from lib/hooks/core/hook-http.js
rename to src/hooks/core/hook-http.js
diff --git a/lib/hooks/index.js b/src/hooks/index.js
similarity index 100%
rename from lib/hooks/index.js
rename to src/hooks/index.js
diff --git a/lib/hooks/userspace/hook-connect.js b/src/hooks/userspace/hook-connect.js
similarity index 100%
rename from lib/hooks/userspace/hook-connect.js
rename to src/hooks/userspace/hook-connect.js
diff --git a/lib/hooks/userspace/hook-express.js b/src/hooks/userspace/hook-express.js
similarity index 100%
rename from lib/hooks/userspace/hook-express.js
rename to src/hooks/userspace/hook-express.js
diff --git a/lib/hooks/userspace/hook-grpc.js b/src/hooks/userspace/hook-grpc.js
similarity index 100%
rename from lib/hooks/userspace/hook-grpc.js
rename to src/hooks/userspace/hook-grpc.js
diff --git a/lib/hooks/userspace/hook-hapi.js b/src/hooks/userspace/hook-hapi.js
similarity index 100%
rename from lib/hooks/userspace/hook-hapi.js
rename to src/hooks/userspace/hook-hapi.js
diff --git a/lib/hooks/userspace/hook-koa.js b/src/hooks/userspace/hook-koa.js
similarity index 100%
rename from lib/hooks/userspace/hook-koa.js
rename to src/hooks/userspace/hook-koa.js
diff --git a/lib/hooks/userspace/hook-mongodb-core.js b/src/hooks/userspace/hook-mongodb-core.js
similarity index 100%
rename from lib/hooks/userspace/hook-mongodb-core.js
rename to src/hooks/userspace/hook-mongodb-core.js
diff --git a/lib/hooks/userspace/hook-mysql.js b/src/hooks/userspace/hook-mysql.js
similarity index 96%
rename from lib/hooks/userspace/hook-mysql.js
rename to src/hooks/userspace/hook-mysql.js
index aeb7a5f..85859c3 100644
--- a/lib/hooks/userspace/hook-mysql.js
+++ b/src/hooks/userspace/hook-mysql.js
@@ -16,10 +16,10 @@
 
 'use strict';
 
-var cls = require('../../../lib/cls.js');
+var cls = require('../../../src/cls.js');
 var shimmer = require('shimmer');
 var semver = require('semver');
-var SpanData = require('../../../lib/span-data.js');
+var SpanData = require('../../../src/span-data.js');
 var agent;
 
 var SUPPORTED_VERSIONS = '^2.9.x';
diff --git a/lib/hooks/userspace/hook-redis.js b/src/hooks/userspace/hook-redis.js
similarity index 100%
rename from lib/hooks/userspace/hook-redis.js
rename to src/hooks/userspace/hook-redis.js
diff --git a/lib/hooks/userspace/hook-restify.js b/src/hooks/userspace/hook-restify.js
similarity index 100%
rename from lib/hooks/userspace/hook-restify.js
rename to src/hooks/userspace/hook-restify.js
diff --git a/lib/logger.js b/src/logger.js
similarity index 100%
rename from lib/logger.js
rename to src/logger.js
diff --git a/lib/span-data.js b/src/span-data.js
similarity index 100%
rename from lib/span-data.js
rename to src/span-data.js
diff --git a/lib/trace-agent.js b/src/trace-agent.js
similarity index 100%
rename from lib/trace-agent.js
rename to src/trace-agent.js
diff --git a/lib/trace-labels.js b/src/trace-labels.js
similarity index 100%
rename from lib/trace-labels.js
rename to src/trace-labels.js
diff --git a/lib/trace-span.js b/src/trace-span.js
similarity index 100%
rename from lib/trace-span.js
rename to src/trace-span.js
diff --git a/lib/trace-writer.js b/src/trace-writer.js
similarity index 100%
rename from lib/trace-writer.js
rename to src/trace-writer.js
diff --git a/lib/trace.js b/src/trace.js
similarity index 100%
rename from lib/trace.js
rename to src/trace.js
diff --git a/lib/tracing-policy.js b/src/tracing-policy.js
similarity index 100%
rename from lib/tracing-policy.js
rename to src/tracing-policy.js
diff --git a/lib/util.js b/src/util.js
similarity index 100%
rename from lib/util.js
rename to src/util.js
diff --git a/test/hooks/common.js b/test/hooks/common.js
index 7a04c6e..5b78a6b 100644
--- a/test/hooks/common.js
+++ b/test/hooks/common.js
@@ -25,7 +25,7 @@ var agent = require('../..').start(config).private_();
 // We want to disable publishing to avoid conflicts with production.
 agent.traceWriter.publish_ = function() {};
 
-var cls = require('../../lib/cls.js');
+var cls = require('../../src/cls.js');
 
 var assert = require('assert');
 var http = require('http');
diff --git a/test/hooks/test-hooks-index.js b/test/hooks/test-hooks-index.js
index 00d9e6f..bfe811e 100644
--- a/test/hooks/test-hooks-index.js
+++ b/test/hooks/test-hooks-index.js
@@ -18,7 +18,7 @@
 var assert = require('assert');
 var Module = require('module');
 var semver = require('semver');
-var index = require('../../lib/hooks/index.js');
+var index = require('../../src/hooks/index.js');
 var findModulePath = index.findModulePath;
 var findModuleVersion = index.findModuleVersion;
 
diff --git a/test/hooks/test-trace-connect.js b/test/hooks/test-trace-connect.js
index 0bf2127..26bace1 100644
--- a/test/hooks/test-trace-connect.js
+++ b/test/hooks/test-trace-connect.js
@@ -15,10 +15,10 @@
  */
 'use strict';
 
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 var http = require('http');
 var assert = require('assert');
-var constants = require('../../lib/constants.js');
+var constants = require('../../src/constants.js');
 var common = require('./common.js');
 var connect = require('./fixtures/connect3');
 
diff --git a/test/hooks/test-trace-express.js b/test/hooks/test-trace-express.js
index 33f7a34..d5a9aa6 100644
--- a/test/hooks/test-trace-express.js
+++ b/test/hooks/test-trace-express.js
@@ -15,10 +15,10 @@
  */
 'use strict';
 
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 var http = require('http');
 var assert = require('assert');
-var constants = require('../../lib/constants.js');
+var constants = require('../../src/constants.js');
 var common = require('./common.js');
 var express = require('./fixtures/express4');
 
diff --git a/test/hooks/test-trace-grpc.js b/test/hooks/test-trace-grpc.js
index 6e91463..f91348c 100644
--- a/test/hooks/test-trace-grpc.js
+++ b/test/hooks/test-trace-grpc.js
@@ -18,7 +18,7 @@
 var common = require('./common.js');
 require('../..').private_().config_.enhancedDatabaseReporting = true;
 var assert = require('assert');
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 
 var versions = {
   grpc1: require('./fixtures/grpc1')
diff --git a/test/hooks/test-trace-hapi.js b/test/hooks/test-trace-hapi.js
index d281352..0fb2307 100644
--- a/test/hooks/test-trace-hapi.js
+++ b/test/hooks/test-trace-hapi.js
@@ -17,10 +17,10 @@
 
 var common = require('./common.js');
 
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 var http = require('http');
 var assert = require('assert');
-var constants = require('../../lib/constants.js');
+var constants = require('../../src/constants.js');
 var semver = require('semver');
 
 var server;
diff --git a/test/hooks/test-trace-http.js b/test/hooks/test-trace-http.js
index edf8194..286179a 100644
--- a/test/hooks/test-trace-http.js
+++ b/test/hooks/test-trace-http.js
@@ -16,8 +16,8 @@
 'use strict';
 
 var common = require('./common.js');
-var constants = require('../../lib/constants.js');
-var TraceLabels = require('../../lib/trace-labels.js');
+var constants = require('../../src/constants.js');
+var TraceLabels = require('../../src/trace-labels.js');
 
 var assert = require('assert');
 var http = require('http');
@@ -218,7 +218,7 @@ describe('test-trace-http', function() {
               assert.equal(spans.length, 5);
               // We need to check a property attached at the end of a span
               var statusCodes = [];
-              var labels = require('../../lib/trace-labels.js');
+              var labels = require('../../src/trace-labels.js');
               for (var j = 0; j < spans.length; j++) {
                 var code = Number(spans[j].labels[
                     labels.HTTP_RESPONSE_CODE_LABEL_KEY]);
diff --git a/test/hooks/test-trace-mongodb.js b/test/hooks/test-trace-mongodb.js
index e8088ab..a050e13 100644
--- a/test/hooks/test-trace-mongodb.js
+++ b/test/hooks/test-trace-mongodb.js
@@ -21,7 +21,7 @@
 // Run a mongo image binding the mongo port
 //   ex) docker run -p 27017:27017 -d mongo
 var common = require('./common.js');
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 var assert = require('assert');
 
 var versions = {
diff --git a/test/hooks/test-trace-mongoose.js b/test/hooks/test-trace-mongoose.js
index c8d6b06..0ea108a 100644
--- a/test/hooks/test-trace-mongoose.js
+++ b/test/hooks/test-trace-mongoose.js
@@ -21,7 +21,7 @@
 // Run a mongo image binding the mongo port
 //   ex) docker run -p 27017:27017 -d mongo
 var common = require('./common.js');
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 
 var assert = require('assert');
 var mongoose = require('./fixtures/mongoose4');
diff --git a/test/hooks/test-trace-mysql.js b/test/hooks/test-trace-mysql.js
index 234daa9..14ce242 100644
--- a/test/hooks/test-trace-mysql.js
+++ b/test/hooks/test-trace-mysql.js
@@ -16,7 +16,7 @@
 'use strict';
 
 var common = require('./common.js');
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 require('../..').private_().config_.enhancedDatabaseReporting = true;
 var assert = require('assert');
 var mysql = require('./fixtures/mysql2');
diff --git a/test/hooks/test-trace-redis.js b/test/hooks/test-trace-redis.js
index 11267e7..39c64ad 100644
--- a/test/hooks/test-trace-redis.js
+++ b/test/hooks/test-trace-redis.js
@@ -21,7 +21,7 @@
 // Run a redis image binding the redis port
 //   ex) docker run -p 6379:6379 -d redis
 var common = require('./common.js');
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 
 var assert = require('assert');
 var versions = {
diff --git a/test/hooks/test-trace-restify.js b/test/hooks/test-trace-restify.js
index 1d2b8a1..2e5e390 100644
--- a/test/hooks/test-trace-restify.js
+++ b/test/hooks/test-trace-restify.js
@@ -15,10 +15,10 @@
  */
 'use strict';
 
-var traceLabels = require('../../lib/trace-labels.js');
+var traceLabels = require('../../src/trace-labels.js');
 var http = require('http');
 var assert = require('assert');
-var constants = require('../../lib/constants.js');
+var constants = require('../../src/constants.js');
 var common = require('./common.js');
 var semver = require('semver');
 var versions = {
diff --git a/test/performance/http/http-performance-runner.js b/test/performance/http/http-performance-runner.js
index 4080a92..f41f759 100644
--- a/test/performance/http/http-performance-runner.js
+++ b/test/performance/http/http-performance-runner.js
@@ -34,7 +34,7 @@ var smileyServer = http.createServer(function(req, res) {
 });
 
 var runInTransaction = function(fn) {
-  var cls = require('../../../lib/cls.js');
+  var cls = require('../../../src/cls.js');
   cls.getNamespace().run(function() {
     var span = traceAgent.createRootSpanData('outer');
     fn(function() {
diff --git a/test/performance/mongo/mongo-performance-runner.js b/test/performance/mongo/mongo-performance-runner.js
index fe80233..6c4f472 100644
--- a/test/performance/mongo/mongo-performance-runner.js
+++ b/test/performance/mongo/mongo-performance-runner.js
@@ -49,7 +49,7 @@ var sim = new Simple({
 });
 
 var runInTransaction = function(fn) {
-  var cls = require('../../../lib/cls.js');
+  var cls = require('../../../src/cls.js');
   cls.getNamespace().run(function() {
     var span = traceAgent.createRootSpanData('outer');
     fn(function() {
diff --git a/test/standalone/test-index.js b/test/standalone/test-index.js
index 328666b..0d5d00d 100644
--- a/test/standalone/test-index.js
+++ b/test/standalone/test-index.js
@@ -23,7 +23,7 @@ if (!process.env.GCLOUD_PROJECT) {
 
 var assert = require('assert');
 var agent = require('../..');
-var cls = require('../../lib/cls.js');
+var cls = require('../../src/cls.js');
 
 describe('index.js', function() {
 
diff --git a/test/standalone/test-trace-header-context.js b/test/standalone/test-trace-header-context.js
index 02d82af..6b6dc2e 100644
--- a/test/standalone/test-trace-header-context.js
+++ b/test/standalone/test-trace-header-context.js
@@ -19,7 +19,7 @@ var common = require('../hooks/common.js');
 var http = require('http');
 var assert = require('assert');
 var express = require('../hooks/fixtures/express4');
-var constants = require('../../lib/constants.js');
+var constants = require('../../src/constants.js');
 
 describe('test-trace-header-context', function() {
   beforeEach(function() {
diff --git a/test/standalone/test-trace-koa.js b/test/standalone/test-trace-koa.js
index 091b0c0..3d48849 100644
--- a/test/standalone/test-trace-koa.js
+++ b/test/standalone/test-trace-koa.js
@@ -19,8 +19,8 @@ var common = require('../hooks/common.js');
 var koa = require('../hooks/fixtures/koa1');
 var http = require('http');
 var assert = require('assert');
-var constants = require('../../lib/constants.js');
-var TraceLabels = require('../../lib/trace-labels.js');
+var constants = require('../../src/constants.js');
+var TraceLabels = require('../../src/trace-labels.js');
 
 var server;
 
diff --git a/test/standalone/test-trace-uncaught-exception.js b/test/standalone/test-trace-uncaught-exception.js
index fb2396f..c400cc9 100644
--- a/test/standalone/test-trace-uncaught-exception.js
+++ b/test/standalone/test-trace-uncaught-exception.js
@@ -18,7 +18,7 @@
 
 var assert = require('assert');
 var nock = require('nock');
-var cls = require('../../lib/cls.js');
+var cls = require('../../src/cls.js');
 var agent = require('../..');
 var request = require('request');
 
diff --git a/test/standalone/test-trace-writer.js b/test/standalone/test-trace-writer.js
index ec49d48..d559598 100644
--- a/test/standalone/test-trace-writer.js
+++ b/test/standalone/test-trace-writer.js
@@ -18,7 +18,7 @@
 
 var assert = require('assert');
 var nock = require('nock');
-var cls = require('../../lib/cls.js');
+var cls = require('../../src/cls.js');
 var agent = require('../..');
 var request = require('request');
 
diff --git a/test/test-constants.js b/test/test-constants.js
index 90f1b47..86d3b36 100644
--- a/test/test-constants.js
+++ b/test/test-constants.js
@@ -17,7 +17,7 @@
 'use strict';
 
 var assert = require('assert');
-var constants = require('../lib/constants.js');
+var constants = require('../src/constants.js');
 
 describe('constants', function() {
   it('has correct values', function() {
diff --git a/test/test-span-data.js b/test/test-span-data.js
index f5cff43..5a915c2 100644
--- a/test/test-span-data.js
+++ b/test/test-span-data.js
@@ -22,9 +22,9 @@ if (!process.env.GCLOUD_PROJECT) {
 }
 
 var agent = require('..').start({ samplingRate: 0 }).private_();
-var TraceLabels = require('../lib/trace-labels.js');
+var TraceLabels = require('../src/trace-labels.js');
 var assert = require('assert');
-var cls = require('../lib/cls.js');
+var cls = require('../src/cls.js');
 
 describe('SpanData', function() {
 
diff --git a/test/test-trace-agent.js b/test/test-trace-agent.js
index 8fd65e1..bdc6226 100644
--- a/test/test-trace-agent.js
+++ b/test/test-trace-agent.js
@@ -16,7 +16,7 @@
 
  'use strict';
 
- var constants = require('../lib/constants.js');
+ var constants = require('../src/constants.js');
 
 if (!process.env.GCLOUD_PROJECT) {
   console.log('The GCLOUD_PROJECT environment variable must be set.');
@@ -25,11 +25,11 @@ if (!process.env.GCLOUD_PROJECT) {
 
 var assert = require('assert');
 var config = require('../config.js');
-var file = require('../lib/trace-agent.js');
-var SpanData = require('../lib/span-data.js');
+var file = require('../src/trace-agent.js');
+var SpanData = require('../src/span-data.js');
 var agent = file.get(config);
-var constants = require('../lib/constants.js');
-var cls = require('../lib/cls.js');
+var constants = require('../src/constants.js');
+var cls = require('../src/cls.js');
 
 describe('Trace Agent', function() {
 
diff --git a/test/test-trace-policy.js b/test/test-trace-policy.js
index 5a14fa0..d602c2b 100644
--- a/test/test-trace-policy.js
+++ b/test/test-trace-policy.js
@@ -17,7 +17,7 @@
 'use strict';
 
 var assert = require('assert');
-var tracingPolicy = require('../lib/tracing-policy.js');
+var tracingPolicy = require('../src/tracing-policy.js');
 
 describe('FilterPolicy', function() {
   it('should not allow filtered urls', function() {
diff --git a/test/test-trace-span.js b/test/test-trace-span.js
index f87c4f7..c41a881 100644
--- a/test/test-trace-span.js
+++ b/test/test-trace-span.js
@@ -18,7 +18,7 @@
 
 var assert = require('assert');
 var tk = require('timekeeper');
-var TraceSpan = require('../lib/trace-span.js');
+var TraceSpan = require('../src/trace-span.js');
 
 
 describe('TraceSpan', function() {
diff --git a/test/test-trace.js b/test/test-trace.js
index 0053b2c..d182b87 100644
--- a/test/test-trace.js
+++ b/test/test-trace.js
@@ -17,7 +17,7 @@
 'use strict';
 
 var assert = require('assert');
-var Trace = require('../lib/trace.js');
+var Trace = require('../src/trace.js');
 
 
 describe('Trace', function() {
diff --git a/test/test-util.js b/test/test-util.js
index 09cbbe1..1c2a32b 100644
--- a/test/test-util.js
+++ b/test/test-util.js
@@ -17,7 +17,7 @@
 'use strict';
 
 var assert = require('assert');
-var util = require('../lib/util.js');
+var util = require('../src/util.js');
 var path = require('path');
 
 var o = {