Is Horizon safe to play?

The official Horizon is reasonably safe to run, with caveats the project states openly. Its code is public under the MIT licence, releases are built by GitHub Actions from that public code, and every release carries a SHA256SUMS file and a signature you can check. The real risks are fakes downloaded from the wrong place and native mods you choose to trust. And because the Windows and macOS apps aren’t code-signed by Microsoft or Apple, your system may warn you the first time.

Where to download Horizon (and where not to)

There are exactly two official sources: playhorizon.dev and the releases of github.com/horizon-rust/horizon. Our download page links straight to those GitHub files and doesn’t host the launcher itself.

Things that are not official Horizon:

• Any APK or Android app. Horizon runs on Windows, macOS and Linux only. Android launchers called Horizon belong to the old Pocket Edition scene, explained in Horizon vs Distant Horizons vs Horizon for PE.
• Anything promising Horizon without a Minecraft license. The real one needs a Microsoft account that owns Java Edition and builds its files from your copy.
• “Minecraft Rust Edition” downloads from other sites. The FAQ notes other projects use that name, including a fork of Horizon.

How to check a download yourself

Every release has SHA256SUMS (a fingerprint of each file) and SHA256SUMS.sig (a signature of that list made with Horizon’s release key). Put the downloaded file and SHA256SUMS in one folder, then:

• Linux: sha256sum -c SHA256SUMS --ignore-missing
• macOS: shasum -a 256 -c SHA256SUMS --ignore-missing
• Windows (PowerShell): Get-FileHash <file>, then compare with the line in SHA256SUMS

Each file should say OK. To check the signature too, download the whole release into a folder and, from a clone of the repository, run cargo run -p horizon-release-sign -- verify --tag <tag> <folder>. The public key is in crates/horizon-release-sign/release-keys.txt.

A note on what the launcher checks for you: the docs disagree. The install page says the launcher doesn’t check the signature for you yet, while “How Horizon is built” and the security notes say the launcher and horizon-server update check signed checksums before installing, and Nightlies carry a second, per-version signature so an old build can’t be passed off as a new one. If it matters to you, check by hand.

What the project does before a release ships

• verify runs on GitHub’s machines for every pull request: formatting, lints, tests, and a check that no Minecraft files are committed.
• parity runs the comparison tests against real Minecraft 26.3 that a change can affect. More in how Horizon checks itself against vanilla.
• A release goes out only after a smoke test (the game starts and draws a world) and while no issue is labelled release-blocker.

What the project admits isn’t solved

Credit where due: the security notes are unusually frank.

• Most code is written by AI agents, and not every line is read by a person; automated checks stand in.
• Code that merges is code that ships. Since 23 October 2026 there is one channel, so a change reaches players within minutes of merging. Signing proves a build came from the pipeline, not that the change was good.
• No code signing from Apple or Microsoft. macOS asks you to confirm the first time; Windows may warn too.
• Some planned protections (a separate GitHub App for agents, required code-owner reviews of the release machinery) were still waiting on the owner in the notes’ status table dated 19 October 2026.

Mods: data is safe, code is a choice

Content mods (.hmod) are data only: blocks, items, recipes, textures. They can’t run anything. Native mods (.hnmod) are Rust code compiled into your game, not sandboxed: they can do anything you can on your computer. The safeguards:

• The registry lists a native mod only after a maintainer has read its source, and the publishing guide says every new version of a native mod is read again.
• The launcher builds native mods only after a red warning that names them, into a game of its own for one instance.
• Authors can sign versions with minisign; signed projects reject unsigned updates.
• A harmful project is taken down, and the launcher then refuses its files and turns installed copies off. The registry’s revocation list shows this in practice: on 3 November 2026 a mod called crossversion was paused while its Microsoft sign-in for online-mode servers was reviewed with its author.

Only build mods whose authors you trust. The install flow is in how to install mods, and every page in our mod catalog shows author, licence and source.

Your account and your data

Horizon signs in through Microsoft’s own page in your browser; you enter a code there rather than typing your password into the launcher. Data collection is off until you switch it on, with four separate switches. The one thing always sent is an anonymous “I’m playing” ping with a random session number, the version, your OS and whether a world is open to LAN, explained in how many people play Horizon.

Bans

Horizon’s docs say nothing about bans. Horizon joins online-mode servers with your real account, as vanilla does, and it identifies itself as a different client (Horizon’s own server can use that to admit only Horizon players). Some servers have rules about non-vanilla clients; read them before you join.

Found a security problem?

Use GitHub’s private vulnerability reporting on the horizon-rust/horizon repository (Security tab, “Report a vulnerability”), not Discord or a public issue.