diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index f3dfcbe5..efe16477 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -6,4 +6,4 @@
 
 ### Tests
 
-- [ ] Run the tests tests with `npm test` or `yarn test`
+- [ ] Run the tests with `npm test` or `yarn test`
diff --git a/src/autoProcess.ts b/src/autoProcess.ts
index b357ea44..dfbf6656 100644
--- a/src/autoProcess.ts
+++ b/src/autoProcess.ts
@@ -55,7 +55,7 @@ type AutoPreprocessOptions = {
   [languageName: string]: TransformerOptions;
 };
 
-export const runTransformer = async (
+export const transform = async (
   name: string,
   options: TransformerOptions,
   { content, map, filename, attributes }: TransformerArgs<any>,
@@ -68,6 +68,7 @@ export const runTransformer = async (
     return options({ content, map, filename, attributes });
   }
 
+  // todo: maybe add a try-catch here looking for module-not-found errors
   const { transformer } = await import(`./transformers/${name}`);
 
   return transformer({
@@ -166,7 +167,7 @@ export function sveltePreprocess(
       return { code: content, dependencies };
     }
 
-    const transformed = await runTransformer(lang, transformerOptions, {
+    const transformed = await transform(lang, transformerOptions, {
       content,
       filename,
       attributes,
@@ -184,11 +185,10 @@ export function sveltePreprocess(
 
   const markup: PreprocessorGroup['markup'] = async ({ content, filename }) => {
     if (transformers.replace) {
-      const transformed = await runTransformer(
-        'replace',
-        transformers.replace,
-        { content, filename },
-      );
+      const transformed = await transform('replace', transformers.replace, {
+        content,
+        filename,
+      });
 
       content = transformed.code;
     }
@@ -214,7 +214,7 @@ export function sveltePreprocess(
     let { code, map, dependencies, diagnostics } = transformResult;
 
     if (transformers.babel) {
-      const transformed = await runTransformer(
+      const transformed = await transform(
         'babel',
         getTransformerOptions('babel'),
         {
@@ -250,7 +250,7 @@ export function sveltePreprocess(
     // istanbul ignore else
     if (await hasDepInstalled('postcss')) {
       if (transformers.postcss) {
-        const transformed = await runTransformer(
+        const transformed = await transform(
           'postcss',
           getTransformerOptions('postcss'),
           { content: code, map, filename, attributes },
@@ -261,7 +261,7 @@ export function sveltePreprocess(
         dependencies = concat(dependencies, transformed.dependencies);
       }
 
-      const transformed = await runTransformer(
+      const transformed = await transform(
         'globalStyle',
         getTransformerOptions('globalStyle'),
         { content: code, map, filename, attributes },
diff --git a/src/modules/language.ts b/src/modules/language.ts
index f64f7014..83552068 100644
--- a/src/modules/language.ts
+++ b/src/modules/language.ts
@@ -1,6 +1,7 @@
 import { basename } from 'path';
 
 import { PreprocessorArgs } from '../types';
+import { isValidLocalPath } from './utils';
 
 export const LANG_SPECIFIC_OPTIONS: Record<string, any> = {
   sass: {
@@ -63,12 +64,10 @@ export const getLanguage = (attributes: PreprocessorArgs['attributes']) => {
     }
 
     alias = attributes.type.replace(/^(text|application)\/(.*)$/, '$2');
-  } else if (attributes.src) {
-    // istanbul ignore if
-    if (typeof attributes.src !== 'string') {
-      throw new Error('src attribute must be string');
-    }
-
+  } else if (
+    typeof attributes.src === 'string' &&
+    isValidLocalPath(attributes.src)
+  ) {
     const parts = basename(attributes.src).split('.');
 
     if (parts.length > 1) {
diff --git a/src/modules/tagInfo.ts b/src/modules/tagInfo.ts
index 2419ff9e..ce9fcb07 100644
--- a/src/modules/tagInfo.ts
+++ b/src/modules/tagInfo.ts
@@ -3,6 +3,7 @@ import { resolve, dirname } from 'path';
 
 import { PreprocessorArgs } from '../types';
 import { getLanguage } from './language';
+import { isValidLocalPath } from './utils';
 
 const resolveSrc = (importerFile: string, srcPath: string) =>
   resolve(dirname(importerFile), srcPath);
@@ -40,7 +41,7 @@ export const getTagInfo = async ({
     let path = attributes.src;
 
     /** Only try to get local files (path starts with ./ or ../) */
-    if (path.match(/^(https?:)?\/\//) == null) {
+    if (isValidLocalPath(path)) {
       path = resolveSrc(filename, path);
       if (await doesFileExist(path)) {
         content = await getSrcContent(path);
diff --git a/src/modules/utils.ts b/src/modules/utils.ts
index f75f8f3a..0ce0dc9b 100644
--- a/src/modules/utils.ts
+++ b/src/modules/utils.ts
@@ -56,3 +56,14 @@ export async function hasDepInstalled(dep: string) {
 
   return (cachedResult[dep] = result);
 }
+
+const REMOTE_SRC_PATTERN = /^(https?:)?\/\//;
+
+export function isValidLocalPath(path: string) {
+  return (
+    path.match(REMOTE_SRC_PATTERN) == null &&
+    // only literal strings allowed
+    !path.startsWith('{') &&
+    !path.endsWith('}')
+  );
+}
diff --git a/test/autoProcess/autoProcess.test.ts b/test/autoProcess/autoProcess.test.ts
index bad55c30..a35eb373 100644
--- a/test/autoProcess/autoProcess.test.ts
+++ b/test/autoProcess/autoProcess.test.ts
@@ -18,6 +18,10 @@ describe('detect - mimetype', () => {
       lang: 'customLanguage',
       targetLanguage: 'customLanguage',
     },
+    {
+      src: '{_potato("foo")}',
+      targetLanguage: null,
+    },
   ];
 
   MIMETYPES.forEach(({ type, lang, src, targetLanguage }) => {
diff --git a/test/autoProcess/externalFiles.test.ts b/test/autoProcess/externalFiles.test.ts
index 974285bd..c736575d 100644
--- a/test/autoProcess/externalFiles.test.ts
+++ b/test/autoProcess/externalFiles.test.ts
@@ -8,7 +8,7 @@ import {
   spyConsole,
 } from '../utils';
 
-const { warnSpy } = spyConsole();
+const { warnSpy } = spyConsole({ silent: true });
 
 const {
   markup: markupProcessor,
@@ -23,6 +23,8 @@ const REMOTE_JS = [
 ];
 
 describe('external files', () => {
+  afterEach(warnSpy.mockClear);
+
   it('should insert external file content and add as deps', async () => {
     const [markup, script, style] = [
       await markupProcessor({