NexusCore Mod (NCM)

v1.1.0 — M4 complete

Rolls up the five builds of the 1.0 line. If you are on v1.0.0, upgrade — it has two confirmed critical defects, both fixed here.

Minecraft 1.21.1 · Java 21 · NeoForge, Fabric, Forge

What changed

• /execute as <player> no longer borrows that player's NexusCore permissions. A substituted command source is refused, and both the audit actor and the rate-limit subject resolve to the real issuer.
• The same fix closed two confused-deputy paths: a run_command click event on a sign, or in a written book on a lectern, built a privileged command source with the clicking player as the entity.
• /teleport no longer bypasses NexusCore. Only /tp was taken over before, so /teleport ran as pure vanilla — no permission check, no rate limit, no audit record.
• Two permission values that failed open now fail closed, and permissions.json is genuinely re-read on /nexus reload instead of being silently overwritten.
• NexusCore now owns the vanilla commands it replaces — /ban /kick /banlist /pardon /list /tp /teleport /gamemode. Opt out with overrideVanillaCommands=false.
• Safe mode: start with -Dnexuscore.safemode=true to run only the core modules and recover a server you otherwise cannot start.
• The command reference is generated from the code and cannot drift — 50 commands, in docs/admin/commands.md.

Known limitations

• /seen <unknown name> can stall the server. IdentityService.resolve() falls back to a blocking Mojang HTTP lookup on the server thread, so a slow or unreachable Mojang API stalls the whole server for as long as the request takes. Reachable by any ordinary player. First item scheduled for 1.1.1.
• Vanish misbehaves for onlookers. Four related faults that appear only on another player's client: chat renders as a validation error, un-vanishing does not restore the entity for clients that saw it vanish, vanish is not re-applied to players who join later, and the vanished set survives death while the invisibility flag does not.
• A second ban or mute does not deactivate the first. /unban lifts one and reports success while the player stays banned; active counts double-count, and the strictest record is not the one returned.
• audit.log never rotates. It is read fully into heap and SHA-256'd on the server thread at startup, at shutdown, and on every verify and tail — unbounded growth plus a synchronous full read.
• A transient read error can quarantine an intact permissions.json. JsonStore.read() quarantines on any IOException, so a one-off read failure moves a healthy file aside and the next boot starts from defaults.
• config.json silently loses operator keys. Loading rewrites the file from the typed object, deleting any key the schema does not know, while reporting no problems found.
• players.json is rewritten in full on every login and logout. Never pruned, and each write copies a full .bak and fsyncs twice.
• Fabric death messages lose their cause. Every styled death reads <Player> died — on Fabric only.
• /pardon and /banlist strand vanilla ban state. Pre-takeover vanilla bans become un-liftable, and /ban-ip and /pardon-ip are separate commands NexusCore never takes over, so IP bans are neither audited nor listed.
• Only one player has ever been online at a time during testing. Everything that needs a second player is unverified — including the four vanish faults above, which appear only on another player's client.
• Every remaining confirmed defect, down to low, is listed in IMPLEMENTATION_STATUS.md rather than withheld.

Upgrading

Existing servers need one operator action after upgrading from 1.0.0: /nexus permission group add default nexuscore.command.core.confirm

Verified

214 automated tests; all three loaders build reproducibly and CI builds all three from a bare checkout. Re-verified 2026-07-27 against the archived release bytes on all three loaders: the installed jar was confirmed by SHA-256 to be byte-identical to archived/v1.1.0/, /nexus version reported 1.1.0, /execute as against a summoned armor stand was refused, the audit chain verified intact, and no NexusCore error was logged. Reproduce with ./verify-release-jar.sh <loader> 1.1.0.

Checksums

0b8a5fccc5b0f57b62a342a17ae9d1a7ceeb4dfa7e74e00d9b887bb434cd94dc  NexusCore-neoforge-1.1.0-1.21.1.jar
a64e845769e8e9bdd8971f0346ed7fd8c070ba426a65d41a7c2f7ba51b9bf212  NexusCore-fabric-1.1.0-1.21.1.jar
4a14fffdf78477a1b09271df861ee2f508d6bbc691292ff1371ed8ceb34f2f44  NexusCore-forge-1.1.0-1.21.1.jar

Full notes: https://github.com/Modzwastaken/NexusCore-Mod-NCM/releases/tag/v1.1.0