diff --git a/src/bundle.ts b/src/bundle.ts
index db65cd1..e8824cf 100644
--- a/src/bundle.ts
+++ b/src/bundle.ts
@@ -100,8 +100,12 @@ export async function bundle(this: EsbuildServerlessPlugin): Promise<void> {
       outdir: path.join(buildDirPath, path.dirname(entry)),
     };
 
-    const pkg: any = await import('esbuild');
-    const context: BuildContext = await pkg?.context(options);
+    const pkg = await import('esbuild');
+
+    type ContextFn = (opts: typeof options) => Promise<BuildContext>;
+    type WithContext = typeof pkg & { context?: ContextFn };
+    const context = await (pkg as WithContext).context?.(options);
+
     let result = await context?.rebuild();
 
     if (!result) {