PrismarineJS Minecraft 26.1.2 compatibility evidence

PR_EVIDENCE.md

PrismarineJS Minecraft 26.1.2 Compatibility Evidence

Prepared on 2026-05-12 as a linked PrismarineJS/Mineflayer compatibility update for Minecraft 26.1.2.

Environment

• macOS, arm64
• Java: 26.0.1
• Vanilla server jar: Minecraft 26.1.2
• GitHub user/fork namespace used for PR preparation: mneuhaus

Key verification results

node-minecraft-data / minecraft-data

Command:

npm test

Result:

499255 OKs
865 passing
exit=0

This includes generated wrapper data and the new 26.1.2 block/item/particle/material/recipe data.

node-minecraft-protocol

Checks run during the compatibility pass:

npm run lint
26.1.2 packet/server/cycle tests: 241 passing
Vanilla 26.1.2 client integration: 4 passing, 2 pending

prismarine-chunk

Command:

npm test

Result:

331 passing
exit=0

prismarine-physics

Command:

npm test

Result:

20 passing
exit=0

mineflayer

Commands:

npm run lint
MC_SERVER_JAR_DIR=/Users/mneuhaus/Workspace/prismarine-26.1.2-evidence/server-jars \
  npx mocha test/externalTest.js --reporter spec --exit -g 'mineflayer_external 26\.1\.2v'

Result:

49 passing
exit=0

The full Mineflayer external suite was run against a real Vanilla Minecraft 26.1.2 server using Java 26.0.1.

prismarine-viewer

Checks run during the compatibility pass:

npm run lint
npm run prepare / webpack build
Browser screenshot smoke test using version 26.1.2

The viewer rendered 26.1.2 chunks in-browser after keeping the bedrock version indexes available in the worker bundle.

Implementation note

These changes were implemented with assistance from GPT-5.5 and then validated locally with the checks listed above.