Lag Doctor 0.3.0 — Paper 26.3 beta

Created by William Liu (@starchlorddotcom), with substantial AI assistance.

This compatibility release targets Paper 26.3 and Java 25+. It updates the pinned Paper API, plugin descriptor, Java bytecode, isolated demo setup and documentation. Commands, configuration and diagnostic behavior are unchanged.

Install

Stop the server, remove any older LagDoctor JAR from plugins/, add LagDoctor-0.3.0.jar, and restart using Java 25+. Keep your existing config. Run /ld report after about a minute.

For Paper 1.21.11, use version 0.2.0. Other Minecraft versions, Spigot and Folia are not supported by this build. Paper 26.3 itself is currently beta; back up and test separately before upgrading a world.

Verified

All 18 automated tests pass. Local Paper 26.3 build 143 verified loading, tick reports, entity scans, scan cancellation, exports with and without locations, comparison overlap rejection, spike detection and incident recovery. The isolated test server stopped cleanly. Large-server overhead and player-client interactions are not validated.

Complete 0.3.0 source, tests, docs and example reports · Release and checksums · Feedback

No telemetry or automatic world changes. Heuristic evidence does not prove lag causes. MIT licensed.