diff --git a/package-lock.json b/package-lock.json
index 3876535..0bf0675 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@exact-realty/esbuild-plugin-closure-compiler",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@exact-realty/esbuild-plugin-closure-compiler",
-      "version": "1.0.0",
+      "version": "1.0.1",
       "license": "Apache-2.0 WITH LLVM-exception",
       "devDependencies": {
         "@types/google-closure-compiler": "^0.0.21",
diff --git a/package.json b/package.json
index 4fc5479..4eeadb3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@exact-realty/esbuild-plugin-closure-compiler",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "description": "esbuild plugin for compiling with Google Closure Compiler as the last step",
   "main": "./dist/index.cjs",
   "module": "./dist/index.mjs",
diff --git a/src/esmDynamicImports.ts b/src/esmDynamicImports.ts
index d16de9b..ba86721 100644
--- a/src/esmDynamicImports.ts
+++ b/src/esmDynamicImports.ts
@@ -19,7 +19,7 @@ const dymamicImportExpressionRegex =
 const preprocess = (text: string): string =>
 	text.replace(
 		dymamicImportExpressionRegex,
-		'globalThis.__reserved__["%dymamic_import%"]',
+		'globalThis["__reserved__"]["%dymamic_import%"]',
 	);
 
 const postprocess = (text: string): string => {
diff --git a/src/esmExports.ts b/src/esmExports.ts
index ba4e6a4..8c7adfb 100644
--- a/src/esmExports.ts
+++ b/src/esmExports.ts
@@ -17,14 +17,14 @@ const preprocess = (text: string): string =>
 	text
 		.replace(
 			/export\s+default\b/g,
-			'/** @nocollapse */globalThis.__reserved__["%export"]["default"]=',
+			'/** @nocollapse */globalThis["__reserved__"]["%export"]["default"]=',
 		)
 		.replace(/export\s*{([^}]+)}/g, (_, p1: string) => {
 			return p1
 				.split(',')
 				.map(
 					(e) =>
-						'/** @nocollapse */globalThis.__reserved__["%export"]' +
+						'/** @nocollapse */globalThis["__reserved__"]["%export"]' +
 						(/\sas\s/.test(e)
 							? e.replace(/(.+)\sas\s(.+)/, (_, p1, p2) => {
 									return `[${JSON.stringify(
diff --git a/src/esmImports.ts b/src/esmImports.ts
index 4e0b877..142e24a 100644
--- a/src/esmImports.ts
+++ b/src/esmImports.ts
@@ -22,7 +22,7 @@ const preprocess = (text: string): string =>
 			importExpressionRegex,
 			(_, defaultExport, starName, namedImports, from, moduleName) => {
 				return (
-					'/** @nocollapse */ globalThis.__reserved__["%import_start"]();' +
+					'/** @nocollapse */ globalThis["__reserved__"]["%import_start"]();' +
 					`${
 						from
 							? `const {${[
@@ -35,8 +35,8 @@ const preprocess = (text: string): string =>
 									.filter(Boolean)
 									.join(',')}}=`
 							: ''
-					}globalThis.__reserved__["%import"](${moduleName});` +
-					'/** @nocollapse */ globalThis.__reserved__["%import_end"]()'
+					}globalThis["__reserved__"]["%import"](${moduleName});` +
+					'/** @nocollapse */ globalThis["__reserved__"]["%import_end"]()'
 				);
 			},
 		)
@@ -45,7 +45,7 @@ const preprocess = (text: string): string =>
 				.split(',')
 				.map(
 					(e) =>
-						'/** @nocollapse */globalThis.__reserved__["%export"]' +
+						'/** @nocollapse */globalThis["__reserved__"]["%export"]' +
 						(/\sas\s/.test(e)
 							? e.replace(/(.+)\sas\s(.+)/, (_, p1, p2) => {
 									return `[${JSON.stringify(
diff --git a/src/getCompiler.ts b/src/getCompiler.ts
index 8813a21..1b0d73f 100644
--- a/src/getCompiler.ts
+++ b/src/getCompiler.ts
@@ -15,14 +15,22 @@
 
 import type esbuild from 'esbuild';
 import googleClosureCompiler from 'google-closure-compiler';
+import * as esmDynamicImports from './esmDynamicImports.js';
 import * as esmExports from './esmExports.js';
 import * as esmImports from './esmImports.js';
-import * as esmDynamicImports from './esmDynamicImports.js';
 import * as umdExports from './umdExports.js';
 
+/* The following functions ensure that external code can include __reserved__
+ in it, without causing interference with the preprocessing and postprocessing
+ functions
+ */
+const preprocessReserved = (x: string) => x.replace(/(__reserved__)/g, '_$1_');
+const postprocessReserved = (x: string) => x.replace(/_(__reserved__)_/g, '$1');
+
 const esm = {
 	preprocess: (x: string): string => {
 		return [
+			preprocessReserved,
 			esmDynamicImports.preprocess,
 			esmExports.preprocess,
 			esmImports.preprocess,
@@ -33,22 +41,25 @@ const esm = {
 			esmDynamicImports.postprocess,
 			esmExports.postprocess,
 			esmImports.postprocess,
+			postprocessReserved,
 		].reduce((acc, cv) => cv(acc), x);
 	},
 };
 
 const umd = {
 	preprocess: (x: string): string => {
-		return [esmDynamicImports.preprocess, umdExports.preprocess].reduce(
-			(acc, cv) => cv(acc),
-			x,
-		);
+		return [
+			preprocessReserved,
+			esmDynamicImports.preprocess,
+			umdExports.preprocess,
+		].reduce((acc, cv) => cv(acc), x);
 	},
 	postprocess: (x: string): string => {
-		return [esmDynamicImports.postprocess, umdExports.postprocess].reduce(
-			(acc, cv) => cv(acc),
-			x,
-		);
+		return [
+			esmDynamicImports.postprocess,
+			umdExports.postprocess,
+			postprocessReserved,
+		].reduce((acc, cv) => cv(acc), x);
 	},
 };
 
@@ -60,34 +71,39 @@ const getCompiler = (
 
 	const buildModule = esmOutput ? esm : umd;
 
-	const compiler = new googleClosureCompiler.compiler({
-		language_in: 'ECMASCRIPT_2020',
-		language_out: 'ECMASCRIPT_2015',
-		env: 'BROWSER',
-		...compilerOptions,
-		rewrite_polyfills: false,
-		process_closure_primitives: false,
-		apply_input_source_maps: false,
-		warning_level: 'QUIET',
-		isolate_polyfills: true,
-		assume_function_wrapper: esmOutput,
-	});
+	// A new instance is needed every time because of how the command lines
+	// are constructed
+	const compilerFactory = () =>
+		new googleClosureCompiler.compiler({
+			language_in: 'ECMASCRIPT_2020',
+			language_out: 'ECMASCRIPT_2015',
+			env: 'BROWSER',
+			...compilerOptions,
+			rewrite_polyfills: false,
+			process_closure_primitives: false,
+			apply_input_source_maps: false,
+			warning_level: 'QUIET',
+			isolate_polyfills: true,
+			assume_function_wrapper: esmOutput,
+		});
 
 	return (text: string) => {
 		text = buildModule.preprocess(text);
 
 		return new Promise<string>((resolve, reject) => {
-			const process = compiler.run((exitCode, stdout, stderr) => {
-				if (exitCode === 0) {
-					// TODO: Warnings
-					stdout = buildModule.postprocess(stdout);
+			const process = compilerFactory().run(
+				(exitCode, stdout, stderr) => {
+					if (exitCode === 0) {
+						// TODO: Warnings
+						stdout = buildModule.postprocess(stdout);
 
-					resolve(stdout);
-				} else {
-					// TODO: Better error handing
-					return reject(new Error(stderr));
-				}
-			});
+						resolve(stdout);
+					} else {
+						// TODO: Better error handing
+						return reject(new Error(stderr));
+					}
+				},
+			);
 
 			if (!process.stdin) {
 				process.kill();