SJMCL
SJMCL, also called SJMC Launcher, is a free, open-source Minecraft launcher for Windows, macOS, and Linux.
What SJMCL is
SJMCL, also called SJMC Launcher, is a free, open-source Minecraft launcher for Windows, macOS, and Linux. Built with the Tauri framework, it keeps separate game directories and instances for saves, mods, resource packs, shader packs, screenshots, and settings. It downloads game clients, mod loaders, resources, and modpacks from sources including CurseForge and Modrinth, with modpack import in both supported directions. Multiple mod loaders and Java runtime management are included, along with automatic updates. Microsoft sign-in, third-party authentication servers, and compatibility with the proposed Yggdrasil Connect OAuth flow provide account options. Deep links connect external webpages and programs, while an MCP service can connect agent applications and automate the running launcher. Downloads include Windows installer and portable builds, macOS Intel and Apple Silicon files, and Linux packages or portable versions. Some features can vary by region, platform, or distribution type. The project is maintained by open-source contributors and is not affiliated with Mojang or Microsoft.
Good
- Free plan with no listed charge
- Separate instances organize saves and settings
- Downloads from CurseForge and Modrinth
- Supports multiple mod loaders
- Java runtime management and automatic updates
Watch out
- Not an official Minecraft product
- Some features vary by region or platform
- Extensions documentation marks the feature as coming soon
- Privacy policy says version data may be sent
Who it suits
It suits Minecraft players who need separate instances, modpack tools, Java management, and cross-platform desktop support. It also fits users interested in external integrations or launcher automation.
Verdict
SJMCL combines instance organization, mod downloads, account options, and Java management in one cross-platform launcher. Check platform and regional limitations before relying on every feature.
The facts
Each one read from SJMCL's own pages, with the date it was checked.
What it does
- Accounts
- It supports Microsoft sign-in and third-party authentication servers, and is compatible with the Yggdrasil Connect OAuth login flow proposal.checked 11 Oct 2026
- Audience and affiliation
- The launcher was initiated by members of Shanghai Jiao Tong University Minecraft Club and is developed with open-source community contributors.checked 11 Oct 2026
- Automatic updates
- Yeschecked 23 Sep 2026
- Automation
- Its MCP service lets external Agent applications automate the launcher while it is running.checked 11 Oct 2026
- Disclaimer
- The maker states that SJMC Launcher is not an official Minecraft product and is not approved by or affiliated with Mojang or Microsoft.checked 11 Oct 2026
- Download formats
- Downloads include Windows x86, x64, and ARM64 installers and portable versions; macOS Apple Silicon and Intel DMG and App Bundle files; and Linux DEB, RPM, and portable versions.checked 11 Oct 2026
- Downloads
- It supports downloading game clients, mod loaders, game resources, and modpacks from sources including CurseForge and Modrinth.checked 11 Oct 2026
- Extensions
- The launcher supports developing extensions, though the documentation marks this feature as coming soon.checked 11 Oct 2026
- External integrations
- Deep links and an MCP service let it work with external webpages, programs, and agent services.checked 11 Oct 2026
- Feature availability
- The maker says some features may be limited by region, operating platform, or distribution type.checked 11 Oct 2026
- Feature limits
- The maker says some features may be limited by region, operating platform, or distribution type.checked 11 Oct 2026
- Instance management
- It manages multiple game directories and instances, including saves, mods, resource packs, shaders, screenshots, and settings.checked 11 Oct 2026
- Instances
- It manages multiple game directories and instances, including saves, mods, resource packs, shader packs, screenshots, and settings.checked 11 Oct 2026
- Java runtime management
- Yeschecked 23 Sep 2026
- MCP integration
- The documentation gives setup instructions for connecting the launcher to Cherry Studio over HTTP.checked 11 Oct 2026
- Mod loader support
- multiplechecked 23 Sep 2026
- Modpack import
- bothchecked 23 Sep 2026
- Operating systems
- The maker lists compatibility with Windows 10/11, macOS, and Linux.checked 11 Oct 2026
- Privacy
- The user agreement says the software may send its version and operating system version to the maker’s servers and does not collect personal information.checked 11 Oct 2026
- Product
- SJMC Launcher is an open-source, cross-platform Minecraft launcher built with the Tauri framework.checked 11 Oct 2026
- Product status
- The maker says the software is not an official Minecraft product and is not approved by or affiliated with Mojang or Microsoft.checked 11 Oct 2026
- Project
- The project was initiated by members of the Shanghai Jiao Tong University Minecraft Society and is developed and maintained with open-source community contributors.checked 11 Oct 2026
Money
- Free plan
- Yeschecked 23 Sep 2026
Where it runs
- Platforms
- The download page lists Windows x86, x64, and ARM64; macOS Apple Silicon and Intel; and Linux packages.checked 11 Oct 2026
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