Polaris

Polaris is a fork of Arcturus Community and is completely independently developed and has no ties to Krews / Team Morningstar

Polaris is a complete, self-contained hotel package: a modern Java game server (formerly known as Arcturus Morningstar Extended), the Octane browser client, a ready-to-import database and all the assets needed to bring a hotel online.

📢 Disclaimer

This repository is provided as an educational resource for learning purposes only. The creators and contributors are not responsible for any misuse or unintended consequences arising from its use. By using these files you agree to take full responsibility for your actions and to comply with all applicable laws and regulations.

• Emulator: Java 21 (JDK) and Maven
• Database: MariaDB

Create an empty MariaDB database and put its name and credentials in config.ini. Polaris creates the schema automatically on first startup; you do not need to import a database dump.

Already running an Arcturus Morningstar 3.5.5 or older Polaris hotel? Make a full database backup first, point Polaris at that database, and start the emulator. A recognized hotel is adopted and upgraded automatically while its users, rooms, items, currencies, settings, and custom tables are preserved. Polaris refuses to modify a non-empty database that does not look like an Arcturus/Polaris hotel.

Automatic migrations are enabled by default. Advanced deployments can set db.migrate.on_startup=false (or DB_MIGRATE_ON_STARTUP=false) after applying migrations separately.

Deployment and troubleshooting commands:

# Apply migrations and exit without starting the hotel
java -jar Polaris-<version>-jar-with-dependencies.jar --migrations-only

# Read-only compatibility, checksum and pending-migration report
java -jar Polaris-<version>-jar-with-dependencies.jar --migrations=validate

--migrations=apply explicitly applies migrations before normal startup. There is no interactive startup prompt, because that would hang Docker, systemd and hosting-panel restarts.

cd emulator
mvn package

The build produces target/Polaris-<version>-jar-with-dependencies.jar. Place a config.ini with your database credentials next to the jar (or set the DB_HOSTNAME, DB_PORT, DB_DATABASE, DB_USERNAME and DB_PASSWORD environment variables) and start it with:

java -jar Polaris-<version>-jar-with-dependencies.jar

Polaris keeps its promise to existing plugin authors:

• Plugin jars built for Arcturus/Morningstar load unchanged — the Java API still lives in the com.eu.habbo.* packages.
• Raw SQL written against pre-Polaris table names is translated on the fly by the legacy bridge. The best-known example: the old permissions table is now split into permission_ranks and permission_definitions, and the bridge rewrites old-style statements (such as ALTER TABLE permissions ADD cmd_x ...) into their new-schema equivalents automatically.

How it works, what it covers and how to configure it is documented in POLARIS.md.

• TheGeneral — the original Arcturus emulator
• The Arcturus Morningstar team (krews.org) — the community fork Polaris grew from
• DuckieTM, simoleo89, Medievalshell, Lorenzo (the wired master), Remco, Dennis (DennisObject)
• Dippy — Improved wired architecture base
• Seth / iSetht — Opacity & Gravity wireds
• Puffin — the MyBoBBa catalogue assets, xlRaiko — the clothing pack
• bop — Easter egg exploit & Nitro Memory Leaks

Need help, want to contribute, or just want to chat?