Add build step

build.mjs

@@ -0,0 +1,66 @@
+import * as esbuild from 'esbuild';
+import process from 'node:process';
+
+const baseConfig = {
+	entryPoints: ['src/index.ts'],
+	bundle: true,
+	logLevel: 'info'
+};
+
+const umdConfig = {
+	...baseConfig,
+	format: 'iife',
+
+	// The following are hacks to basically make this an UMD module. No native support for that in esbuild as of today
+	globalName: 'Metamuxer',
+
+	footer: {
+		js:
+`if (typeof module === "object" && typeof module.exports === "object") Object.assign(module.exports, Metamuxer)`
+	}
+};
+
+const esmConfig = {
+	...baseConfig,
+	format: 'esm'
+};
+
+let ctxUmd = await esbuild.context({
+	...umdConfig,
+	outfile: 'dist/metamuxer.js'
+});
+let ctxEsm = await esbuild.context({
+	...esmConfig,
+	outfile: 'dist/metamuxer.mjs'
+});
+let ctxUmdMinified = await esbuild.context({
+	...umdConfig,
+	outfile: 'dist/metamuxer.min.js',
+	minify: true
+});
+let ctxEsmMinified = await esbuild.context({
+	...esmConfig,
+	outfile: 'dist/metamuxer.min.mjs',
+	minify: true
+});
+
+if (process.argv[2] === '--watch') {
+	await Promise.all([
+		ctxUmd.watch(),
+		ctxEsm.watch(),
+		ctxUmdMinified.watch(),
+		ctxEsmMinified.watch(),
+	]);
+} else {
+	ctxUmd.rebuild();
+	ctxEsm.rebuild();
+	ctxUmdMinified.rebuild();
+	ctxEsmMinified.rebuild();
+
+	await Promise.all([
+		ctxUmd.dispose(),
+		ctxEsm.dispose(),
+		ctxUmdMinified.dispose(),
+		ctxEsmMinified.dispose(),
+	]);
+}