Every colder message here checks get_available_bytes() before it reads, and has a test named for it. Snapshots and events -- twenty and sixty times a second, the two that actually matter -- did neither. A snapshot's counts are a u8 and two u16s read straight off the wire and then looped without a bounds check. A garbage enemy count is up to 65535 dictionaries built out of an empty buffer, and a garbage tick is fed directly to the client's clock estimate and its input-lead resync. The channel is unreliable and ENet's checksum is off, so a short snapshot is a network event, not only an attack. It now answers valid:false and the client drops it -- one dropped snapshot costs 50ms of interpolation. Events were worse in kind. The decoder read a type byte and matched on it, so a type it did not recognise consumed one byte and carried on, reading every field after it at the wrong offset: one stray byte became a stream of bullets spawned at invented positions, which the client then applied. Lengths are now declared up front and an unknown type stops the stream. The prefix is kept, because the channel is reliable and ordered and throwing the packet away would strand every despawn in it. Both size tables are pinned to their encoders by tests that encode one of each record and compare, so they cannot drift -- and a new SimEvent.Type with no declared length fails a test rather than shipping. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Transcience
Top-down twin-stick bullet-hell with a dedicated, server-authoritative backend. Godot 4.7, GDScript, no external runtime dependencies.
Play
tools/server.sh # dedicated server on :27015
tools/client.sh --join --name ada # connect a client
Or run one client and press Host and play for a listen server.
Controls — WASD move, mouse aim, LMB fire, E to pick up loot and to use the hub's portals and quartermaster, 1–4 use an inventory slot, shift+1–4 drop one, hold F for one second to escape a dungeon, Esc menu, F1 hitbox overlay. Every one of those is rebindable in Settings.
What is here
| Twin-stick bullet hell | Server-simulated bullet field, ~300 concurrent bullets at 0.28 ms/tick — around 60x headroom against the 60 Hz budget. |
| Authoritative multiplayer | Clients send input and nothing else. Hits, damage, death, loot, upgrades and instance transfers are all server decisions. Prediction and reconciliation for the local player. |
| Enemies | Five readable movements (static, drift, orbit, approach, strafe) composed with bullet emitters. Nothing deals contact damage; every threat is a bullet you can see. |
| Two bosses | The Warden of the Fold stands still through four phases. The Cantor of the Vault walks a circuit, chases, orbits, and marks the floor before it strikes. Both are pure data. |
| Three dungeons | Two real runs, one per boss, plus a Proving Grounds: the same content at a fraction of the health and ten times the drop rate, for testing by hand. |
| Characters | Up to five living per account, permadeath, levels 1–15, experience shared across the party undivided. |
| Inventory and loot | Four slots, always on screen. Loot is either world-shared or instanced per player, and the instanced kind is filtered on the wire rather than hidden in the client. |
| Upgrades | Seven, drawn three at a time and spent at a hub NPC. Damage, fire rate, extra projectiles, splitting, poison, and a legendary that deletes enemy bullets. |
| Emergency escape | A one-second channel back to the hub that damage does not interrupt — because if it did, quitting the process would be the better escape. Dropping your connection runs the same channel. |
| Settings | Rebindable controls and volumes, and an in-game credits screen. |
Develop
tools/check.sh # parse-check every script ~5s
tools/test.sh # 468 GUT tests, headless ~4s
tools/smoke.sh # server + 4 bot clients over ENet ~40s
Read CLAUDE.md first — it is short, and the Godot CLI gotchas in it will otherwise cost an afternoon.
Docs
- docs/ROADMAP.md — what is built, what is next, where each feature lives
- docs/DECISIONS.md — settled design decisions and their reasoning
- docs/ARCHITECTURE.md — code map and the node-free simulation
- docs/NETCODE.md — replication model, hit validation, known gaps
- docs/WORKFLOW.md — agent-assisted Godot development, and the verification traps this project has actually hit
- docs/ASSETS.md — asset packs and their licence findings
- CREDITS.md — third-party attribution
- CLAUDE.md — commands, invariants, Godot CLI gotchas
Not ready for the internet
LocalAuthProvider lets any client claim any account id. It exists to have the
same shape as Steamworks so swapping is one class, and it must be replaced
before this is reachable from anywhere untrusted. There is no transport
encryption either. See docs/ROADMAP.md.