MegaMek, MegaMekLab, and MekHQ 0.50.06 Released

Hi Everyone!

Welcome to Milestone Release 0.50.06!

We’re pleased to announce the immediate release of MegaMek 0.50.06 as a Milestone Version. This quick follow-up to 0.50.05 addresses a couple of issues in 0.50.05 while delivering a new Milestone for our users. Before we get into the details I want to give everyone a reminder of the two major release types.

Understanding Our Release Types

Milestone Builds

Like a well-maintained Thunderbolt, Milestone builds have proven themselves reliable in the field. These are Development releases that have been thoroughly tested by the community and found free of major bugs. Released roughly every 9-12 months, and we try to offer the perfect balance between stability and updated features.

It’s important to note that “Milestone” doesn’t mean completely bug-free—rather, these builds are less likely to contain game-breaking issues, with most remaining bugs being minor nuisances that have known workarounds. Best for: Players that want a stay on a release with a low risk of bugs, good for new players.

Development Builds

Development builds are like prototype ‘Meks fresh from the factory—packed with new features but not fully battle-tested. While generally stable, they may have occasional quirks or unexpected behavior, similar to a temperamental targeting computer. Best for: Veteran players that crave the rush of new stuff, not to be confused with Necrosia infused players that want the nightly releases for that you need the Discord

Moving to a new Milestone (Critical step if on Java 11)

Currently, most players are using either the previous Milestone (0.49.19.1) or a recent Development release. With version 0.50.06 now being designated as a Milestone, we’re providing a new Milestone for all players to move from 0.49.19.1 to 0.50.06.

It is CRITICAL if you’re using 0.49.19.1 with Java 11 you MUST update to Java 17 to run the new Milestone. Please see this link for instructions

About This Release

While version 0.50.05 was a very strong release overall, it contained a couple of bugs related to C3 computers that required reloading as a workaround. Because of this issue, we made the decision not to designate 0.50.05 as a Milestone Release. But like the old 0.49.7 it was a contender and a strong release.

For the past three weeks, the development team has worked incredibly hard and with remarkable speed to focus exclusively on bug fixes across all three programs. This dedicated effort has led to our unusual decision to release version 0.50.06 as a Milestone immediately without the usual feedback period.

Players using our nightly builds and our test pilots have reported:

No major bugs discovered
Only a few minor irritants remaining
Exceptional stability across all systems

Without further ado, below you’ll find an abbreviated list of the fixes and small improvements included in this release.

MegaMek

We have around 88 bug fixes in this release and the change logs will list them all. But a few we want to call out a couple of the key ones.

MegaMekLab

Around 27 Bug fixes, with a major focus on the printing the record sheets. But a few to call out.

Looking Ahead: The Road to Version 50.07 and Beyond

Extended Development Cycle

Our current development team is the largest, most diverse, and most skilled in history of the projects. After discussion, we’ve decided it’s time to start modernizing some of the code dating back to MegaMek’s original inception.

This modernization effort:

Will likely introduce some bugs in upcoming releases (Starting in 0.50.07)
Is why we’re planning a longer development cycle (with version 50.07 targeted for Q3 2025)

The extended development window will give us the necessary time to update the codebase while implementing several new features. If you’ve been following our development releases, you’ve already started to see meaningful improvements, which will continue across all programs.

GitHub and how we store the file in the Data folder

Significant changes are coming specifically to how we store and manage our data on GitHub. These changes will be implemented during the 0.50.07 release cycle. We’ll be releasing a detailed announcement explaining the specifics of these changes in about a week. This information will be particularly important for developers who use MegaMek’s data in their projects.

Java 21 and Beyond

All of these improvements are necessary to better position ourselves for compatibility with Java 21 and beyond. The significant changes and improvements already visible in recent development releases will continue across all programs as we move forward.

Community Input: Equipment Rules

One of our key initiatives is to thoroughly evaluate what equipment rules MegaMek doesn’t currently have implemented. We will soon open a dedicated forum thread on the official forums where we will:

List equipment rules we know are not implemented or only partially implemented
Invite community feedback to identify gaps we may have missed
Gather thoughts on prioritization and implementation approaches

A Note on MegaMek’s Future

I know some aspects of this post might prompt speculation, but we want to be clear: there is nothing concerning happening with MegaMek/MegaMekLab/MekHQ. We simply finally have the resources and team to start digging in and taking the programs to the next level.

Don’t expect dramatic visual changes—the programs will always maintain its classic interface that “looks like a year 2000 accounting program.” That’s part of its charm! However, under the hood, we’re working toward:

More state-of-the-art, responsive code
Better logging for easier bug identification
Fixes for long-standing pain points in gameplay
Positioning ourselves for long-requested features and improvements

All of these improvements will take time, and we view 50.06 as both a launching point and the next step for players to move too. It allows us to focus on the development cycle without the pressure of an aging Milestone release (0.49.19.1) using a Java version (Java 11) that we have moved past.

Player Options Going Forward

Version 0.50.06 serves as a good point for players who prefer reliability while we embark on our next development releases. Players have two paths forward:

Stick with 0.50.06 as a Milestone release while we work on bigger changes
When 0.50.07 drops in Q3 join us for the development experience

Technical Stuff

Java 17 is Required for all 0.50.x Releases

It’s crucial to read the directions carefully, especially Step 6, which covers a recent change to the Adoptium installer. Make sure to select “Install for all users of this machine” in the Installation Scope. We will continue using Java 17 until Fall 2026. If you choose to use a Java version beyond 17, it isn’t officially supported, and our standard response for issues will be to revert to Java 17. We recommend upgrading to Java 17 before the new release; if you are running 0.49.12-Development or later, it will run on Java 17.

WARNING: Java 24 was released (18 March 2025)! MegaMek still only requires Java 17 (with plans to start officially testing Java 21 end of this year) but we know some of you like living on the bleeding edge of Java. If you are still running on an older OS that is 32-Bit (chances are some of you are), DO NOT INSTALL JAVA 24!!! It has officially dropped support for 32-bit Windows. This impacts those of you on Windows 10 or older.

Important: MekHQ Campaign Update Instructions

It is critical to follow these steps to ensure the integrity of your MekHQ campaign when updating between versions. Failure to follow these steps can result in the corruption of your campaign file.

Treat each release as stand-alone; Copy, never Move your data forward from older versions. MekHQ is NOT backward compatible.

Complete all ongoing contracts in your current campaign, save, and exit the program.
Make a backup of your campaign and custom files. This is a critical step to prevent data loss!
DO NOT COPY MegaMek saves or any preference file from a different version to avoid compatibility issues.
Update MekHQ to the latest version. NEVER overwrite the existing folder; always keep each version in its own folder.
In the new version, load your save file in MekHQ and advance the game by one day.
Re-save any custom presets to ensure they are updated with the new version’s settings.
Exit MekHQ and restart the application to complete the update process.

A Few Reminders and Stuff

The Milestone System Summary

Please see this link for details on the replacement for the old Stable and Development cycle.

How to automatically report bugs: Turn on Sentry

To maintain optimal performance in your MegaMek missions, we’ve integrated Sentry into our systems for efficient bug tracking and error resolution. Sentry monitors issues in real time and automatically generates detailed bug reports, helping us fix problems swiftly and keep you focused on the fight.

🔒 Your Privacy Matters:

Sentry is designed to respect your privacy. It does not track any personal information
By default, Sentry is turned OFF. You have complete control over whether to enable it

📝 How to Enable Sentry if you want to help:

Open the sentry.properties file (located in the root of the program folder) in a text editor of your choice
Once open, change the line enabled=false to enabled=true and save the file

The other information in the file is the Server information where Sentry sends its bug reports. We have a channel on our Discord where only Developers/Engineers get notified of the reports. Here is an example: Sentry 3

State of the Universe (February 18, 2025)

If you haven’t given the State of the Universe (read here if you missed it) a read, please do. There’s lots of information in there that is still recent and relevant.

Planetary Data Editor

The 0.50.04 release includes a new Planetary Data Editor as an alpha feature. This editor works with our newly implemented YAML-based planetary data system, making it significantly easier to view and modify planetary information.

The editor allows you to work with individual planet files rather than the previous approach of massive XML files that were difficult to navigate and edit. Each planet now has its own dedicated file containing all relevant information in one place - basic data, population changes, faction histories, and SICS codes.

This new feature is part of our larger initiative to improve usability for campaign managers and data contributors. We have an Alpha version of the Planet Editor available here Planetary Systems Editor (ALPHA). Since this only edits at this time you’ll need to make sure you keep back-ups of the original local files. Use at your own risk.

For more information about the planetary system rework, visit: Planetary System File Rework

Note: Being an ALPHA feature, we welcome your feedback and bug reports.

User Data Directory for MegaMek, MegaMekLab, and MekHQ

Key Points:

Set a Custom Directory: Choose any location on your computer (e.g., D:/myMMStuff) to keep your game resources.
File Placement:
- Fonts and units (.mtf, .blk) can be placed anywhere within this directory.
- Camo images in /data/images/camo/
- Portrait images in /data/images/portraits/
- Unit fluff images in /data/images/fluff/<unit type>/
- Rank and award definition files (.xml) in /data/universe/
Consistent Access: Resources in this directory are usable across different game versions and modules without needing to relocate them for each new install.
Implementation: Set up this directory via the client settings. A game restart is required for changes to take effect.

Join our official MegaMek Discord, our primary community hub for the suite. We offer superior voice support, individual channels, and assistance for the official public servers. We’re also part of community Discords Everything BattleTech and Classic BattleTech. Find us on Facebook at MegaMek BattleTech and MegaMek.

Contributing

Change Logs (Release Specific) and Download Links

Thank you for your continued support of MegaMek. We’re excited about the future of the project and grateful to have such a dedicated community along for the journey!