diff --git a/lib/esbuild.ex b/lib/esbuild.ex
index 67cab50..314720e 100644
--- a/lib/esbuild.ex
+++ b/lib/esbuild.ex
@@ -188,6 +188,19 @@ defmodule Esbuild do
     |> elem(1)
   end
 
+  def json_library() do
+    case Application.get_env(:esbuild, :json_library) do
+      nil ->
+        case Code.ensure_loaded(JSON) do
+          {:module, _} -> JSON
+          {:error, _} -> Jason
+        end
+
+      lib ->
+        lib
+    end
+  end
+
   defp start_unique_install_worker() do
     ref =
       __MODULE__.Supervisor
diff --git a/lib/esbuild/npm_registry.ex b/lib/esbuild/npm_registry.ex
index b85ce77..7d68d06 100644
--- a/lib/esbuild/npm_registry.ex
+++ b/lib/esbuild/npm_registry.ex
@@ -37,7 +37,7 @@ defmodule Esbuild.NpmRegistry do
       }
     } =
       fetch_file!(url)
-      |> Jason.decode!()
+      |> Esbuild.json_library().decode!()
 
     %{"sig" => signature} =
       signatures