diff --git a/README.md b/README.md
index 87bceb0..235468d 100644
--- a/README.md
+++ b/README.md
@@ -74,21 +74,21 @@ docuri.arity({ type: 'mytype', subtype: 'mysubtype' });
 // 3
 ```
 
-### `docuri([definition])`
-Use custom definition:
+### `docuri.definition([array])`
+Access or use custom definition:
 ```js
-docuri();
+docuri.definition();
 // ['type', 'id', 'subtype', 'index', 'version']
-docuri(['id', 'meta']);
-docuri();
-// ['id', 'meta']
-docuri.parse('42/answer');
+docuri
+  .definition(['id', 'meta'])
+  .parse('42/answer');
 // {
 //   id: '42',
 //   meta: 'answer'
 // }
 ```
-Note: `definition` MUST be an array of strings with at least one item.
+Note: the (optional) argument to `docuri.definition` MUST be an array of strings
+containing at least one item.
 
 
 ## Browser support
diff --git a/index.js b/index.js
index 67f29ae..b808a1d 100644
--- a/index.js
+++ b/index.js
@@ -7,8 +7,11 @@
 
 // type/id/subtype/index/version
 var DEFINITION = ['type', 'id', 'subtype', 'index', 'version'];
+var docuri;
 
-function docuri(definition) {
+module.exports = exports = docuri = {};
+
+docuri.definition = function(definition) {
   if (definition) {
     DEFINITION = definition;
 
diff --git a/package.json b/package.json
index 9a9be9b..ab7a466 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "docuri",
-  "version": "2.2.0",
+  "version": "3.0.0",
   "description": "Rich document ids for CouchDB",
   "main": "index.js",
   "scripts": {
diff --git a/test/config_test.js b/test/config_test.js
deleted file mode 100644
index 8badff8..0000000
--- a/test/config_test.js
+++ /dev/null
@@ -1,28 +0,0 @@
-var test = require('tap').test;
-var docuri = require('..');
-
-test('default configuration', function(t) {
-  t.deepEqual(docuri(), ['type', 'id', 'subtype', 'index', 'version'], 'should return default parts');
-  t.end();
-});
-
-test('set configuration', function(t) {
-  var parts = ['my', 'parts'];
-  t.type(docuri(parts).merge, 'function', 'should return docuri api: merge');
-  t.type(docuri(parts).parse, 'function', 'should return docuri api: parse');
-  t.type(docuri(parts).stringify, 'function', 'should return docuri api: stringify');
-  t.end();
-});
-
-test('change configuration', function(t) {
-  var parts = ['my', 'parts'];
-  docuri(parts);
-  t.deepEqual(docuri(), parts, 'should return custom parts');
-  t.end();
-});
-
-test('use changed configuration', function(t) {
-  var parts = ['my', 'parts'];
-  t.deepEqual(docuri(parts).parse('one/two'), { my: 'one', parts: 'two'}, 'should use custom parts');
-  t.end();
-});
diff --git a/test/definition_test.js b/test/definition_test.js
new file mode 100644
index 0000000..f55269f
--- /dev/null
+++ b/test/definition_test.js
@@ -0,0 +1,28 @@
+var test = require('tap').test;
+var definition = require('..').definition;
+
+test('default configuration', function(t) {
+  t.deepEqual(definition(), ['type', 'id', 'subtype', 'index', 'version'], 'should return default parts');
+  t.end();
+});
+
+test('set configuration', function(t) {
+  var parts = ['my', 'parts'];
+  t.type(definition(parts).merge, 'function', 'should return docuri api: merge');
+  t.type(definition(parts).parse, 'function', 'should return docuri api: parse');
+  t.type(definition(parts).stringify, 'function', 'should return docuri api: stringify');
+  t.end();
+});
+
+test('change configuration', function(t) {
+  var parts = ['my', 'parts'];
+  definition(parts);
+  t.deepEqual(definition(), parts, 'should return custom parts');
+  t.end();
+});
+
+test('use changed configuration', function(t) {
+  var parts = ['my', 'parts'];
+  t.deepEqual(definition(parts).parse('one/two'), { my: 'one', parts: 'two'}, 'should use custom parts');
+  t.end();
+});