RunLab

Pressing F6 generates a fresh world and searches for a structure close to spawn, then places the player beside it after a 10-second countdown. The structure is picked from a configurable pool that covers villages, ruined portals, desert temples and shipwrecks, and the landing spot is chosen on solid ground 30 to 50 blocks from the target, so a run can start at a shipwreck's ship or a portal without manual searching.

Two timers are shown during a run: real-time (RTA) and in-game time (IGT). The timers keep counting until the Ender Dragon is killed, and the time saved by the run is recorded at that point. A structure-only mode generates a plain world with the timer running, which suits practicing exploration on its own. Seeds can be regenerated with F6 and restarted with R, and the pool can be edited with the runlab commands, including reset and setpool.

RunLab is a Fabric mod and runs on client and server, so the server and every player need it. Files are published for Minecraft 1.16.1 and 1.16.5, with 1.0.0 for 1.16.5 as the latest build, under the MIT License. The mod is not open source.