diff --git a/scripts/build.mjs b/scripts/build.mjs
index 955a06b..effd94e 100644
--- a/scripts/build.mjs
+++ b/scripts/build.mjs
@@ -1,5 +1,7 @@
 import * as esbuild from "esbuild";
-import { defaultBuildOptions } from "./shared.mjs";
+import { defaultBuildOptions, writeManifest } from "./shared.mjs";
+
+writeManifest();
 
 await esbuild.build({
 	...defaultBuildOptions,
diff --git a/scripts/manifest.mjs b/scripts/manifest.mjs
new file mode 100644
index 0000000..415fcf6
--- /dev/null
+++ b/scripts/manifest.mjs
@@ -0,0 +1,56 @@
+/* eslint-disable */
+const manifest = {
+	manifest_version: 3,
+	name: "ProToots",
+	version: "1.1.2",
+
+	icons: {
+		48: "icons/icon small_size/icon small_size.png",
+		96: "icons/icon small_size/icon small_size.png",
+	},
+
+	description: "puts pronouns next to usernames on mastodon",
+	homepage_url: "https://github.com/ItsVipra/ProToots",
+	permissions: ["storage", "activeTab"],
+
+	action: {
+		default_icon: "icons/icon small_size/icon small_size.png",
+		default_title: "Enable ProToots on this page",
+	},
+	content_scripts: [
+		{
+			matches: ["*://*/*"],
+			js: ["content_scripts/protoots.js"],
+			css: ["styles/proplate.css"],
+			run_at: "document_start",
+		},
+	],
+
+	options_ui: {
+		page: "options/options.html",
+		browser_style: false,
+	},
+
+	browser_specific_settings: {
+		gecko: {
+			id: "protoots@trans.rights",
+		},
+	},
+};
+
+const firefoxManifest = {
+	...manifest,
+	background: {
+		scripts: ["background/worker.js"],
+	},
+};
+
+const chromeManifest = {
+	...manifest,
+	background: {
+		service_worker: "background/worker.js",
+		type: "module",
+	},
+};
+
+export { firefoxManifest, chromeManifest };
diff --git a/scripts/shared.mjs b/scripts/shared.mjs
index 761ce8d..d238562 100644
--- a/scripts/shared.mjs
+++ b/scripts/shared.mjs
@@ -1,6 +1,8 @@
 import copyPluginPkg from "@sprout2000/esbuild-copy-plugin";
 import path from "path";
 const { copyPlugin } = copyPluginPkg; // js and your fucking mess of imports, sigh.
+import { firefoxManifest, chromeManifest } from "./manifest.mjs";
+import fs from "fs";
 
 /**
  * This array contains all files that we want to handle with esbuild.
@@ -47,3 +49,21 @@ export const defaultBuildOptions = {
 		}),
 	],
 };
+
+/** Writes the manifest for the current browser to the dist folder. */
+export const writeManifest = () => {
+	const allowedBrowsers = ["firefox", "chrome"];
+	const browser = process.env.TARGET ?? "firefox";
+
+	if (!allowedBrowsers.includes(browser)) {
+		throw new Error(
+			"The browser set via the TARGET environment is not valid. Only 'firefox' or 'chrome' are allowed.",
+		);
+	}
+
+	const { outdir } = defaultBuildOptions;
+	if (!fs.existsSync(outdir)) fs.mkdirSync(outdir);
+
+	const manifest = JSON.stringify(browser === "firefox" ? firefoxManifest : chromeManifest);
+	fs.writeFileSync(path.join(outdir, "manifest.json"), manifest, { flag: "w" });
+};
diff --git a/scripts/watch.mjs b/scripts/watch.mjs
index 75e61fd..da9cde8 100644
--- a/scripts/watch.mjs
+++ b/scripts/watch.mjs
@@ -1,4 +1,7 @@
 import * as esbuild from "esbuild";
-import { defaultBuildOptions } from "./shared.mjs";
+import { defaultBuildOptions, writeManifest } from "./shared.mjs";
+
+writeManifest();
+
 let ctx = await esbuild.context(defaultBuildOptions);
 await ctx.watch();
diff --git a/src/manifest.json b/src/manifest.json
deleted file mode 100644
index 2029b9a..0000000
--- a/src/manifest.json
+++ /dev/null
@@ -1,41 +0,0 @@
-{
-	"manifest_version": 3,
-	"name": "ProToots",
-	"version": "1.1.2",
-
-	"icons": {
-		"48": "icons/icon small_size/icon small_size.png",
-		"96": "icons/icon small_size/icon small_size.png"
-	},
-
-	"description": "puts pronouns next to usernames on mastodon",
-	"homepage_url": "https://github.com/ItsVipra/ProToots",
-	"permissions": ["storage", "activeTab"],
-
-	"action": {
-		"default_icon": "icons/icon small_size/icon small_size.png",
-		"default_title": "Enable ProToots on this page"
-	},
-	"background": {
-		"scripts": ["background/worker.js"]
-	},
-	"content_scripts": [
-		{
-			"matches": ["*://*/*"],
-			"js": ["content_scripts/protoots.js"],
-			"css": ["styles/proplate.css"],
-			"run_at": "document_start"
-		}
-	],
-
-	"options_ui": {
-		"page": "options/options.html",
-		"browser_style": false
-	},
-
-	"browser_specific_settings": {
-		"gecko": {
-			"id": "protoots@trans.rights"
-		}
-	}
-}