diff --git a/packages/jsdoc-bus/LICENSE b/packages/jsdoc-bus/LICENSE
new file mode 100644
index 00000000..d6456956
--- /dev/null
+++ b/packages/jsdoc-bus/LICENSE
@@ -0,0 +1,202 @@
+
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diff --git a/packages/jsdoc-bus/README.md b/packages/jsdoc-bus/README.md
new file mode 100644
index 00000000..6c2350fc
--- /dev/null
+++ b/packages/jsdoc-bus/README.md
@@ -0,0 +1,11 @@
+# @jsdoc/bus
+
+An event bus with no dependencies.
+
+## Installing the package
+
+Using npm:
+
+```shell
+npm install --save @jsdoc/bus
+```
diff --git a/packages/jsdoc-bus/index.js b/packages/jsdoc-bus/index.js
new file mode 100644
index 00000000..7f66abcd
--- /dev/null
+++ b/packages/jsdoc-bus/index.js
@@ -0,0 +1,3 @@
+const EventBus = require('./lib/bus');
+
+module.exports = EventBus;
diff --git a/packages/jsdoc-bus/lib/bus.js b/packages/jsdoc-bus/lib/bus.js
new file mode 100644
index 00000000..b68c2f7d
--- /dev/null
+++ b/packages/jsdoc-bus/lib/bus.js
@@ -0,0 +1,49 @@
+const EventEmitter = require('events').EventEmitter;
+const ow = require('ow');
+
+const cache = {};
+const hasOwnProp = Object.prototype.hasOwnProperty;
+
+/**
+ * An event bus that works the same way as a standard Node.js event emitter, with a few key
+ * differences:
+ *
+ * + When you create an event bus, you must specify its name. Consider using your package's name.
+ * + Event buses are cached and shared by default. If module A and module B both create an event bus
+ * called `foo`, both modules get the same event bus. This behavior makes it easier to share one
+ * event bus among all of the modules in your package.
+ *
+ *     To prevent a new event bus from being cached and shared, set the `opts.ignoreCache` property
+ *     to `true` when you create the event bus. (Setting this property to `true` also forces a new
+ *     event bus to be created, even if there's a cached event bus with the same name.)
+ *
+ * @alias module:@jsdoc/bus
+ * @extends module:events.EventEmitter
+ */
+class EventBus extends EventEmitter {
+    /**
+     * Create a new event bus, or retrieve the cached event bus for the ID you specify.
+     *
+     * @param {(string|Symbol)} id - The ID for the event bus.
+     * @param {Object} opts - Options for the event bus.
+     * @param {boolean} [opts.ignoreCache=false] - Set to `true` to prevent the event bus from being
+     * cached, and to return a new event bus even if there is already an event bus with the same ID.
+     */
+    constructor(id, opts = {}) {
+        super();
+
+        ow(id, ow.any(ow.string, ow.symbol));
+
+        if (hasOwnProp.call(cache, id) && !opts.ignoreCache) {
+            return cache[id];
+        }
+
+        this._id = id;
+
+        if (!opts.ignoreCache) {
+            cache[id] = this;
+        }
+    }
+}
+
+module.exports = EventBus;
diff --git a/packages/jsdoc-bus/package-lock.json b/packages/jsdoc-bus/package-lock.json
new file mode 100644
index 00000000..06004be6
--- /dev/null
+++ b/packages/jsdoc-bus/package-lock.json
@@ -0,0 +1,21 @@
+{
+	"name": "@jsdoc/bus",
+	"version": "0.0.1",
+	"lockfileVersion": 1,
+	"requires": true,
+	"dependencies": {
+		"ow": {
+			"version": "0.15.0",
+			"resolved": "https://registry.npmjs.org/ow/-/ow-0.15.0.tgz",
+			"integrity": "sha512-iHHqr8OXsZzBjUkOVxfSR8opBhEhdQUGE4mxZEWehQawHxhCcnnGXrfu6+HhLG3XTK+oHRD/dlfGwNdY9HTHxQ==",
+			"requires": {
+				"type-fest": "^0.8.1"
+			}
+		},
+		"type-fest": {
+			"version": "0.8.1",
+			"resolved": "https://registry.npmjs.org/type-fest/-/type-fest-0.8.1.tgz",
+			"integrity": "sha512-4dbzIzqvjtgiM5rw1k5rEHtBANKmdudhGyBEajN01fEyhaAIhsoKNy6y7+IN93IfpFtwY9iqi7kD+xwKhQsNJA=="
+		}
+	}
+}
diff --git a/packages/jsdoc-bus/package.json b/packages/jsdoc-bus/package.json
new file mode 100644
index 00000000..8f69bb11
--- /dev/null
+++ b/packages/jsdoc-bus/package.json
@@ -0,0 +1,25 @@
+{
+  "name": "@jsdoc/bus",
+  "version": "0.0.1",
+  "description": "An event bus with no dependencies.",
+  "main": "index.js",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/jsdoc3/jsdoc"
+  },
+  "keywords": [
+    "jsdoc"
+  ],
+  "author": {
+    "name": "Jeff Williams",
+    "email": "jeffrey.l.williams@gmail.com"
+  },
+  "license": "Apache-2.0",
+  "bugs": {
+    "url": "https://github.com/jsdoc3/jsdoc/issues"
+  },
+  "homepage": "https://github.com/jsdoc3/jsdoc#readme",
+  "dependencies": {
+    "ow": "^0.15.0"
+  }
+}
diff --git a/packages/jsdoc-bus/test/specs/index.js b/packages/jsdoc-bus/test/specs/index.js
new file mode 100644
index 00000000..d84285ff
--- /dev/null
+++ b/packages/jsdoc-bus/test/specs/index.js
@@ -0,0 +1,12 @@
+describe('@jsdoc/bus', () => {
+    const EventBus = require('../..');
+    const LibBus = require('../../lib/bus');
+
+    it('exists', () => {
+        expect(EventBus).toBeFunction();
+    });
+
+    it('is ./lib/bus', () => {
+        expect(EventBus).toBe(LibBus);
+    });
+});
diff --git a/packages/jsdoc-bus/test/specs/lib/bus.js b/packages/jsdoc-bus/test/specs/lib/bus.js
new file mode 100644
index 00000000..d2eee8ca
--- /dev/null
+++ b/packages/jsdoc-bus/test/specs/lib/bus.js
@@ -0,0 +1,66 @@
+describe('@jsdoc/bus/lib/bus', () => {
+    const EventBus = require('../../../lib/bus');
+    const EventEmitter = require('events').EventEmitter;
+
+    const ignoreCache = { ignoreCache: true };
+
+    it('inherits from EventEmitter', () => {
+        expect(new EventBus('foo', ignoreCache) instanceof EventEmitter).toBeTrue();
+    });
+
+    it('accepts a string for the ID', () => {
+        function makeBus() {
+            return new EventBus('foo', ignoreCache);
+        }
+
+        expect(makeBus).not.toThrow();
+    });
+
+    it('accepts a Symbol for the ID', () => {
+        function makeBus() {
+            return new EventBus(Symbol('foo'), ignoreCache);
+        }
+
+        expect(makeBus).not.toThrow();
+    });
+
+    it('throws on bad IDs', () => {
+        function crashBus() {
+            return new EventBus(true, ignoreCache);
+        }
+
+        expect(crashBus).toThrowError();
+    });
+
+    it('uses a cache by default', () => {
+        let fired = false;
+        const id = Symbol('cache-test');
+        const bus1 = new EventBus(id);
+        const bus2 = new EventBus(id);
+
+        bus1.once('foo', () => {
+            fired = true;
+        });
+
+        bus2.emit('foo');
+
+        expect(bus1).toBe(bus2);
+        expect(fired).toBeTrue();
+    });
+
+    it('ignores the cache when asked', () => {
+        let fired = false;
+        const id = Symbol('cache-test');
+        const bus1 = new EventBus(id, ignoreCache);
+        const bus2 = new EventBus(id, ignoreCache);
+
+        bus1.once('foo', () => {
+            fired = true;
+        });
+
+        bus2.emit('foo');
+
+        expect(bus1).not.toBe(bus2);
+        expect(fired).toBeFalse();
+    });
+});