diff --git a/.env b/.env
index a0c1181..8fede7c 100644
--- a/.env
+++ b/.env
@@ -1,2 +1,2 @@
-VITE_APP_GITHUB_REPO_NAME=radish19/momonga-lang-playground
-VITE_APP_GITHUB_REPO_URL=https://github.com/radish19/momonga-lang-playground
+VITE_APP_GITHUB_REPO_NAME=derarion/momonga-lang-playground
+VITE_APP_GITHUB_REPO_URL=https://github.com/derarion/momonga-lang-playground
diff --git a/LICENSE b/LICENSE
index 10265e8..1161370 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2023 radish19
+Copyright (c) 2023 derarion
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index 96b0590..2b5eced 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 Welcome to the Momonga playground!  
 Momonga, named after [the Japanese flying squirrel](https://simple.wikipedia.org/wiki/Japanese_dwarf_flying_squirrel), is a programming language designed for complete beginners.
 
-You can try it [here](https://radish19.github.io/momonga-lang-playground/)!
+You can try it [here](https://derarion.github.io/momonga-lang-playground/)!
 
 :warning: Momonga is still Under Development, but you can try some of its features.
 
@@ -95,7 +95,7 @@ Please refer to [Language Overview](#language-overview) section.
 ### No Setup
 
 Most programming languages require setting up an environment to run code, which might reduce learners' motivation.  
-Momonga runs on the [playground](https://radish19.github.io/momonga-lang-playground/), so users need nothing but a web browser.
+Momonga runs on the [playground](https://derarion.github.io/momonga-lang-playground/), so users need nothing but a web browser.
 
 ## Language Overview