Made for the way you play.

Most clients are a mod with a launcher bolted on, and it shows the moment you alt-tab: two different greys, two different accent colours, two different ideas about what a button looks like.

Serenity picks six colours per palette and the launcher, the in-game menu and this website all derive everything else from those same six. Panels, borders, the sky behind them — all arithmetic on the same inputs, so a palette added in one place has already decided what it looks like in the others.

There are four palettes: Nebula, Verdant, Lagoon and Twilight. The theme control in the footer changes this site's, and the same four are in the launcher.

The client is a Stonecutter project: one source tree with one subproject per Minecraft version. Where Mojang renamed a class, the source is written in the newest name and the older targets have the old one written in for them.

That is what makes seven lines maintainable by a small project. It is also why 1.16 is offered by the launcher but wears vanilla's menu — it needs Java 8, and holding the shared source to Java 8 for one line costs more than that line is worth.

The launcher is Tauri 2: a Rust core with a web frontend, using the system webview rather than shipping a browser. The cosmetics service is Rust and axum.

Not your password, and not your session token. Signing in to the launcher is Microsoft's own auth-code flow with PKCE — the launcher opens Microsoft's page and never sees what you type into it. Tokens are kept in your operating system's keychain, not in a file next to the settings.

The cosmetics service proves who you are through Mojang's third-party handshake: it issues a random, single-use, two-minute nonce, you tell Mojang you are joining a server with that id, and the service asks Mojang whether that happened. Your access token never reaches us.

What a player record holds is a UUID, the username Mojang returned, a list of granted cosmetic ids, and which cape is being worn. The public endpoint other players' clients call to draw you returns your UUID and your cape and nothing else.

Serenity is not an official Minecraft product, and is not approved by or associated with Mojang or Microsoft. Minecraft is a trademark of Mojang AB.

No game files are redistributed here. The client jar, libraries, assets and natives are downloaded from Mojang's official endpoints when you launch, and verified by SHA-1. You need a legitimate copy of Minecraft and you sign in with your own account.

Version artwork in the launcher is art the project has the right to distribute. Mojang's key art is not redistributable, so none of it ships.