diff --git a/src/config.ts b/src/config.ts
index 6155995..8dd6526 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -158,7 +158,7 @@ const notifications = {
 	playSound: envOrString(process.env.PLAY_SOUND),
 	pushbullet: envOrString(process.env.PUSHBULLET),
 	pushover: {
-		priority: envOrString(process.env.PUSHOVER_PRIORITY),
+		priority: envOrNumber(process.env.PUSHOVER_PRIORITY),
 		token: envOrString(process.env.PUSHOVER_TOKEN),
 		username: envOrString(process.env.PUSHOVER_USER)
 	},
diff --git a/src/index.ts b/src/index.ts
index 591e4c5..53725e6 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -11,7 +11,7 @@ import {tryLookupAndLoop} from './store';
 puppeteer.use(stealthPlugin());
 if (config.browser.lowBandwidth) {
 	puppeteer.use(resourceBlock({
-		blockedTypes: new Set(['image', 'font'])
+		blockedTypes: new Set(['image', 'font'] as const)
 	}));
 } else {
 	puppeteer.use(adBlocker);
diff --git a/src/notification/pushover.ts b/src/notification/pushover.ts
index 07c1ca1..b939eb4 100644
--- a/src/notification/pushover.ts
+++ b/src/notification/pushover.ts
@@ -1,6 +1,6 @@
 import {Link, Store} from '../store/model';
 import {Print, logger} from '../logger';
-import Push from 'pushover-notifications';
+import Push, {PushoverMessage} from 'pushover-notifications';
 import {config} from '../config';
 
 const pushover = config.notifications.pushover;
@@ -13,7 +13,7 @@ export function sendPushoverNotification(link: Link, store: Store) {
 	if (pushover.token && pushover.username) {
 		logger.debug('↗ sending pushover message');
 
-		const message = {
+		const message: PushoverMessage = {
 			message: link.cartUrl ? link.cartUrl : link.url,
 			priority: pushover.priority,
 			title: Print.inStock(link, store)
diff --git a/src/notification/sound.ts b/src/notification/sound.ts
index 082fa8f..c3e0d05 100644
--- a/src/notification/sound.ts
+++ b/src/notification/sound.ts
@@ -1,9 +1,9 @@
+import playerLib, {PlaySound} from 'play-sound';
 import {config} from '../config';
 import fs from 'fs';
 import {logger} from '../logger';
-import playerLib from 'play-sound';
 
-let player: any;
+let player: PlaySound;
 
 if (config.notifications.playSound) {
 	player = playerLib();
@@ -11,7 +11,7 @@ if (config.notifications.playSound) {
 	if (player.player === null) {
 		logger.warn('✖ couldn\'t find sound player');
 	} else {
-		const playerName: string = player.player;
+		const playerName = player.player;
 		logger.info(`✔ sound player found: ${playerName}`);
 	}
 }
diff --git a/src/types/play-sound.d.ts b/src/types/play-sound.d.ts
index c366eeb..8a9dd53 100644
--- a/src/types/play-sound.d.ts
+++ b/src/types/play-sound.d.ts
@@ -1 +1,22 @@
-declare module 'play-sound';
+declare module 'play-sound' {
+	export interface Options {
+		players?: string[];
+		player?: string;
+	}
+
+	export interface PlayOptions {
+		[key: string]: any;
+	}
+
+	export interface PlaySound {
+		player: string;
+
+		play: ((file: string, callback: (error: Error) => void) => PlayerProcess) & ((file: string, options: PlayOptions, callback: (error: Error) => void) => PlayerProcess);
+	}
+
+	export interface PlayerProcess {
+		kill: () => void;
+	}
+
+	export default function (options?: Options): PlaySound;
+}
diff --git a/src/types/puppeteer-extra-plugin-block-resources.d.ts b/src/types/puppeteer-extra-plugin-block-resources.d.ts
index a8be065..e8b2fa2 100644
--- a/src/types/puppeteer-extra-plugin-block-resources.d.ts
+++ b/src/types/puppeteer-extra-plugin-block-resources.d.ts
@@ -1 +1,25 @@
-declare module 'puppeteer-extra-plugin-block-resources';
+declare module 'puppeteer-extra-plugin-block-resources' {
+	import {PuppeteerExtraPlugin} from 'puppeteer-extra';
+
+	export type ResourceType =
+		'document' |
+		'eventsource' |
+		'fetch' |
+		'font' |
+		'image' |
+		'manifest' |
+		'media' |
+		'other' |
+		'script' |
+		'stylesheet' |
+		'texttrack' |
+		'websocket' |
+		'xhr';
+
+	export interface Options {
+		availableTypes?: Set<ResourceType>;
+		blockedTypes?: Set<ResourceType>;
+	}
+
+	export default function (options?: Options): PuppeteerExtraPlugin;
+}
diff --git a/src/types/pushbullet.d.ts b/src/types/pushbullet.d.ts
index 5f82479..3303893 100644
--- a/src/types/pushbullet.d.ts
+++ b/src/types/pushbullet.d.ts
@@ -1 +1,59 @@
-declare module '@hijef/pushbullet';
+declare module '@hijef/pushbullet' {
+	export type DeviceParams = string | number | Record<string, any>;
+
+	export type PushBulletCallback = ((error: Error) => void) | ((error?: null, response: any) => void);
+
+	export interface ListOptions {
+		active?: boolean;
+		cursor?: string;
+		limit?: number;
+	}
+
+	export interface HistoryOptions extends ListOptions {
+		modified_after?: number;
+	}
+
+	export interface PushBulletStream {
+		connect: () => void;
+		close: () => void;
+		on: ((event: 'connect' | 'close' | 'nop', callback: () => void) => void) & ((event: 'error', callback: (error: any) => void) => void) & ((event: 'message', callback: (message: any) => void) => void) & ((event: 'tickle', callback: (tickle: any) => void) => void) & ((event: 'push', callback: (push: any) => void) => void);
+	}
+
+	export class PushBullet {
+		constructor(apiKey: string, options?: {fullResponses: boolean}): this;
+		me(callback: PushBulletCallback);
+		devices(options: ListOptions, callback: PushBulletCallback);
+		devices(callback: PushBulletCallback);
+		createDevice(options: Record<string, any>, callback: PushBulletCallback);
+		updateDevice(deviceIden: string, deviceOptions: Record<string, any>, callback: PushBulletCallback);
+		deleteDevice(deviceIden: string, callback: PushBulletCallback);
+		note(deviceParams: DeviceParams, title: string, body: string, callback: PushBulletCallback);
+		link(deviceParams: DeviceParams, name: string, url: string, body: string, callback: PushBulletCallback);
+		file(deviceParams: DeviceParams, filePath: string, message: string, callback: PushBulletCallback);
+		dismissPush(pushIden: DeviceParams, callback: PushBulletCallback);
+		deletePush(pushIden: DeviceParams, callback: PushBulletCallback);
+		deleteAllPushes(callback: PushBulletCallback);
+		history(options: HistoryOptions, callback: PushBulletCallback);
+		history(callback: PushBulletCallback);
+		subscriptions(options: ListOptions, callback: PushBulletCallback);
+		subscriptions(callback: PushBulletCallback);
+		subscribe(channelTag: string, callback: PushBulletCallback);
+		unsubscribe(subscriptionIden: string, callback: PushBulletCallback);
+		muteSubscription(subscriptionIden: string, callback: PushBulletCallback);
+		unmuteSubscription(subscriptionIden: string, callback: PushBulletCallback);
+		channelInfo(channelTag: string, callback: PushBulletCallback);
+		chats(options: ListOptions, callback: PushBulletCallback);
+		chats(callback: PushBulletCallback);
+		createChat(email: string, callback: PushBulletCallback);
+		deleteChat(chatIden: string, callback: PushBulletCallback);
+		muteChat(chatIden: string, callback: PushBulletCallback);
+		unmuteChat(chatIden: string, callback: PushBulletCallback);
+		sendSMS(options: Record<string, any>, callback: PushBulletCallback);
+		sendClipboard(options: Record<string, any>, callback: PushBulletCallback);
+		dismissEphemeral(options: Record<string, any>, callback: PushBulletCallback);
+		stream(): PushBulletStream;
+		enableEncryption(encryptionPassword: string, userIden: string): PushBulletStream;
+	}
+
+	export default PushBullet;
+}
diff --git a/src/types/pushover-notifications.d.ts b/src/types/pushover-notifications.d.ts
index 93f67cf..cdb4fe1 100644
--- a/src/types/pushover-notifications.d.ts
+++ b/src/types/pushover-notifications.d.ts
@@ -1 +1,55 @@
-declare module 'pushover-notifications';
+declare module 'pushover-notifications' {
+	export type PushoverCallback = ((error: Error) => void) | ((error?: null, response: any) => void);
+
+	export type Sound =
+		'pushover' |
+		'bike' |
+		'bugle' |
+		'cashregister' |
+		'classical' |
+		'cosmic' |
+		'falling' |
+		'gamelan' |
+		'incoming' |
+		'intermission' |
+		'magic' |
+		'mechanical' |
+		'pianobar' |
+		'siren' |
+		'spacealarm' |
+		'tugboat' |
+		'alien' |
+		'climb' |
+		'persistent' |
+		'echo' |
+		'updown' |
+		'vibrate' |
+		'none';
+
+	export interface PushoverOptions {
+		token: string;
+		user: string;
+		httpOptions?: {proxy: string};
+		onerror?: (error: Error | string) => void;
+		update_sounds?: boolean;
+	}
+
+	export interface PushoverMessage {
+		message: string;
+		file?: string | {name: string; data: string};
+		device?: string;
+		title?: string;
+		url?: string;
+		url_title?: string;
+		priority?: number;
+		sound?: Sound;
+		timestamp?: number;
+	}
+
+	export class Pushover {
+		constructor(options: PushoverOptions);
+		send(message: PushoverMessage, callback: PushoverCallback);
+	}
+
+	export default Pushover;
+}