diff --git a/src/lib/dbus.ts b/src/lib/dbus.ts
index aa1e887f..9fe1dee5 100644
--- a/src/lib/dbus.ts
+++ b/src/lib/dbus.ts
@@ -1,15 +1,27 @@
 import { getBus, Error as DBusError } from 'dbus';
 import { promisify } from 'util';
 import { TypedError } from 'typed-error';
+import * as _ from 'lodash';
 
 import log from './supervisor-console';
+import DBus = require('dbus');
 
 export class DbusError extends TypedError {}
 
-const bus = getBus('system');
-const getInterfaceAsync = promisify(bus.getInterface.bind(bus));
+let bus: DBus.DBusConnection;
+let getInterfaceAsync: <T = DBus.AnyInterfaceMethod>(
+	serviceName: string,
+	objectPath: string,
+	ifaceName: string,
+) => Promise<DBus.DBusInterface<T>>;
+
+export const initialized = _.once(async () => {
+	bus = getBus('system');
+	getInterfaceAsync = promisify(bus.getInterface.bind(bus));
+});
 
 async function getSystemdInterface() {
+	await initialized();
 	try {
 		return await getInterfaceAsync(
 			'org.freedesktop.systemd1',
@@ -21,7 +33,8 @@ async function getSystemdInterface() {
 	}
 }
 
-export async function getLoginManagerInterface() {
+async function getLoginManagerInterface() {
+	await initialized();
 	try {
 		return await getInterfaceAsync(
 			'org.freedesktop.login1',
diff --git a/test/legacy/.mocharc.js b/test/legacy/.mocharc.js
index 0d987580..6a4ee1c4 100644
--- a/test/legacy/.mocharc.js
+++ b/test/legacy/.mocharc.js
@@ -8,6 +8,7 @@ module.exports = {
 		'tsconfig-paths/register',
 		'test/lib/chai.ts',
 		'test/legacy/fixtures.ts',
+		'test/lib/legacy-mocha-hooks.ts'
 	],
 	spec: ['test/legacy/**/*.spec.ts'],
 	timeout: '30000',
diff --git a/test/legacy/fixtures.ts b/test/legacy/fixtures.ts
index e1389438..09bbbed0 100644
--- a/test/legacy/fixtures.ts
+++ b/test/legacy/fixtures.ts
@@ -31,6 +31,5 @@ fs.writeFileSync(
 	fs.readFileSync('./test/data/testconfig.json'),
 );
 
-import '~/test-lib/mocked-dbus';
 import '~/test-lib/mocked-dockerode';
 import '~/test-lib/mocked-iptables';
diff --git a/test/lib/legacy-mocha-hooks.ts b/test/lib/legacy-mocha-hooks.ts
new file mode 100644
index 00000000..21fbda83
--- /dev/null
+++ b/test/lib/legacy-mocha-hooks.ts
@@ -0,0 +1,70 @@
+// TODO: Remove this file when all legacy tests have migrated to unit/integration.
+
+import { stub, SinonStub } from 'sinon';
+import * as dbus from 'dbus';
+import { Error as DBusError, DBusInterface } from 'dbus';
+import { initialized } from '~/src/lib/dbus';
+
+let getBusStub: SinonStub;
+
+export const mochaHooks = {
+	async beforeAll() {
+		getBusStub = stub(dbus, 'getBus').returns({
+			getInterface: (
+				serviceName: string,
+				_objectPath: string,
+				_interfaceName: string,
+				interfaceCb: (err: null | DBusError, iface: DBusInterface) => void,
+			) => {
+				if (/systemd/.test(serviceName)) {
+					interfaceCb(null, {
+						StartUnit: () => {
+							// noop
+						},
+						RestartUnit: () => {
+							// noop
+						},
+						StopUnit: () => {
+							// noop
+						},
+						EnableUnitFiles: () => {
+							// noop
+						},
+						DisableUnitFiles: () => {
+							// noop
+						},
+						GetUnit: (
+							_unitName: string,
+							getUnitCb: (err: null | Error, unitPath: string) => void,
+						) => {
+							getUnitCb(null, 'this is the unit path');
+						},
+						Get: (
+							_unitName: string,
+							_property: string,
+							getCb: (err: null | Error, value: unknown) => void,
+						) => {
+							getCb(null, 'this is the value');
+						},
+					} as any);
+				} else {
+					interfaceCb(null, {
+						Reboot: () => {
+							// noop
+						},
+						PowerOff: () => {
+							// noop
+						},
+					} as any);
+				}
+			},
+		} as dbus.DBusConnection);
+
+		// Initialize dbus module before any tests are run so any further tests
+		// that interface with lib/dbus use the stubbed busses above.
+		await initialized();
+	},
+	afterAll() {
+		getBusStub.restore();
+	},
+};
diff --git a/test/lib/mocked-dbus.ts b/test/lib/mocked-dbus.ts
deleted file mode 100644
index ae9496f8..00000000
--- a/test/lib/mocked-dbus.ts
+++ /dev/null
@@ -1,67 +0,0 @@
-import * as dbus from 'dbus';
-import { Error as DBusError, DBusInterface } from 'dbus';
-import { stub } from 'sinon';
-
-/**
- * Because lib/dbus invokes dbus.getBus on module import,
- * getBus needs to be stubbed at the root level due how JS
- * `require` works. lib/dbus interfaces with the systemd and
- * logind interfaces, which expose the unit methods below.
- *
- * There should be no need to un-stub dbus.getBus at any point
- * during testing, since we never want to interact with the actual
- * dbus system socket in the test environment.
- *
- * To test interaction with lib/dbus, import lib/dbus into the test suite
- * and stub the necessary methods, as you would with any other module.
- */
-stub(dbus, 'getBus').returns({
-	getInterface: (
-		serviceName: string,
-		_objectPath: string,
-		_interfaceName: string,
-		interfaceCb: (err: null | DBusError, iface: DBusInterface) => void,
-	) => {
-		if (/systemd/.test(serviceName)) {
-			interfaceCb(null, {
-				StartUnit: () => {
-					// noop
-				},
-				RestartUnit: () => {
-					// noop
-				},
-				StopUnit: () => {
-					// noop
-				},
-				EnableUnitFiles: () => {
-					// noop
-				},
-				DisableUnitFiles: () => {
-					// noop
-				},
-				GetUnit: (
-					_unitName: string,
-					getUnitCb: (err: null | Error, unitPath: string) => void,
-				) => {
-					getUnitCb(null, 'this is the unit path');
-				},
-				Get: (
-					_unitName: string,
-					_property: string,
-					getCb: (err: null | Error, value: unknown) => void,
-				) => {
-					getCb(null, 'this is the value');
-				},
-			} as any);
-		} else {
-			interfaceCb(null, {
-				Reboot: () => {
-					// noop
-				},
-				PowerOff: () => {
-					// noop
-				},
-			} as any);
-		}
-	},
-} as dbus.DBusConnection);