diff --git a/src/index.ts b/src/index.ts
index db693cf..d3e8b06 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -89,23 +89,34 @@ async function load(resolveFrom: string, options, logger): Promise<PathMapType>
 	return result;
 }
 
-async function loadConfig(options, resolveFrom) {
+async function loadConfigByName(names, options, resolveFrom) {
 	let result = await loadConfigUtil(
 		options.inputFS,
 		resolveFrom,
-		['tsconfig.json', 'tsconfig.js'],
+		names,
 		options.projectRoot
 	);
 	if (!result?.config) {
-		throw new Error(`Missing or invalid tsconfig.json in project root (${options.projectRoot})`);
+		throw new Error(`Missing or invalid ${names.join(',')} in project root (${options.projectRoot})`);
 	}
 	return result.config;
 }
 
+async function loadCompilerOptions(options, resolveFrom) {
+	let baseConfig = await loadConfigByName(['tsconfig.json', 'tsconfig.js'], options, resolveFrom)
+	if (!baseConfig.extends) {
+		return baseConfig.compilerOptions
+	}
+	let extendsConfig = await loadConfigByName([baseConfig.extends], options, resolveFrom)
+	return extendsConfig?.compilerOptions || baseConfig?.compilerOptions ? {
+		...baseConfig?.compilerOptions,
+		...extendsConfig?.compilerOptions
+	} : null
+}
+
 /** Populate a map with any paths from tsconfig.json starting from baseUrl */
 async function loadTsPaths(resolveFrom: string, options, logger): Promise<PathMapType> {
-	let config = await loadConfig(options, resolveFrom);
-	let compilerOptions = config?.['compilerOptions'];
+	let compilerOptions = await loadCompilerOptions(options, resolveFrom);
 	if (!compilerOptions) {
 		throw new Error(`Couldn't find compilerOptions in tsconfig`);
 	}