Capsule: deployment & hardening

Use when changing server bind/config, the build pipeline, or the input-hardening surface.

Read first

• docs/design/hardening.md — full hardening section
• docs/design/client-stress-tests.md — bounded report ingestion and the RTS_RECORD_STRESS_TESTS persistence gate

Run / build

cd server && cargo run            # serves client + /ws on RTS_ADDR; open the printed URL
cd server && cargo run --release  # fast build
cd server && cargo build && cargo clippy
node scripts/check-wiki.mjs       # wiki routes, generated stats, and catalog parity
node scripts/check-crate-boundaries.mjs

No JS build step (plain ES modules + PixiJS from CDN). The client is served from ../client relative to the server crate, so cargo run from server/ is the whole dev loop. Release Docker builds do have a prediction-WASM generation step: they run scripts/build-sim-wasm.sh inside the builder image and fail if client/vendor/sim-wasm/rts_sim_wasm.js or rts_sim_wasm_bg.wasm is missing.

Invariants

• Clients are untrusted. Validate and bound every wire input:
  • ordinary command unit lists deduped + capped (MAX_UNITS_PER_COMMAND); lab command-limit bypass lists use the larger bounded LAB_MAX_UNITS_PER_COMMAND
  • WebSocket frames size-limited
  • placement coords range/overflow-checked
• No panics on tick or network paths. Stale ids = no-op. Use checked_* arithmetic on anything derived from client input. Debug builds have overflow checks on (a bad Build coord can panic in cargo run but silently wrap in --release). Keep placement math checked_*.
• Keep the room task alive: handle errors, don’t propagate panics out of message handlers.
• rts-server is the only crate that may own Axum/Tokio WebSocket/static-file serving.
• Missing static asset URLs must not fall back to the SPA shell. App routes may fall back to index.html, but /vendor, /src, /assets, and root asset files should return 404 when the requested file is absent.
• Deploy drain is bounded. SIGTERM/Ctrl-C starts the 295s app drain inside Fly’s 300s stop window: natural match drain, forced aborted finalization for eligible live matches, tracked match-history/replay write wait, then WebSocket/Axum slack. Beta/mainline validation should check logs for forced-finalization success/failure, match recorded outcome=aborted replay=true, and any write-wait timeout before treating an interrupted deploy as healthy.
• /wiki is server-rendered and read-only. It may serve only allowlisted Markdown from docs/context and docs/design; /wiki/stats must be generated from rts-rules definitions and faction catalogs, not scraped from client config or rendered docs.

Cross-capsule triggers

• Touching the wire surface → protocol.md.
• Touching sim correctness → server-sim.md.