Add LTS26 runtime feed

[rwkay]

What is the problem this request aims to solve?

LTS26 was released yesterday 21st May 2026 it has its own runtime feed https://gms.yoyogames.com/Zeus-Runtime-LTS2026.rss

gm-cli should be aware of this and allow downloads and use of the runtimes on that feed

How do you suggest we solve this problem?

Add the feed https://gms.yoyogames.com/Zeus-Runtime-LTS2026.rss

Are there any alternative ways to solve this problem you want to suggest?

No response

[opera-eadelhult]

GM-CLI uses Igor to fetch GMS2 runtimes, so assuming Igor is updated to support LTS 2026, it should suffice to do the following two commands:

Delete outdated Igor that's missing the new RSS feed
(Note, Igor is currently cached separately for each project you have, so you may have to run this in multiple directories or manually remove the .gmcache directory)

gm-cli cache clean  

Run GM-CLI again. When running GM-CLI again and it picks the latest runtime installed, or if the cache is empty downloads the latest one from the Internet.

gm-cli run

Or if you want to be explicit you can use the toolchain flag

gm-cli run --toolchain=GMS2@2026

Note

However, it looks like there is an issue with project tool that breaks GM-CLI, at least for me on Mac, I won't close this issue before that is solve.

Easier fix coming later today

Also, I might release a gm-cli@2.0.0 later today which auto-purges all caches of both the old runtime and Igor to make sure everyone get's the latest LTS by default.

[tedmahsun]

Hi @opera-eadelhult! Thanks for such a quick response.

Confirming this is not Mac only. Same project-tool 404 reproduces on Windows after a manual cache clean.

Repro:
gm-cli cache clean
gm-cli compile --toolchain=GMS2@2026

Result:
npm error code E404
npm error 404 Not Found - GET https://gmpm.gamemaker.io/@gm-tools/project-tool-win-x64 - no such package available

Environment:

• gm-cli@1.4.1
• Windows 11
• GameMaker LTS 2026 IDE installed (runtime 2026.0.0.23 available locally under C:\ProgramData\GameMakerStudio2-LTS2026\...)

[opera-eadelhult]

Thanks! @stuckie just confirmed that this is an issue with the GMPM servers that they are working on to fix. Will resolve this issue once it's working again