chore: move rivetkit to task model

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[railway-app]

🚅 Deployed to the rivet-pr-4680 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
website	😴 Sleeping (View Logs)	Web	Apr 20, 2026 at 6:18 am
frontend-cloud	❌ Build Failed (View Logs)	Web	Apr 20, 2026 at 12:09 am
frontend-inspector	❌ Build Failed (View Logs)	Web	Apr 20, 2026 at 12:09 am
mcp-hub	✅ Success (View Logs)	Web	Apr 20, 2026 at 12:09 am
ladle	❌ Build Failed (View Logs)	Web	Apr 20, 2026 at 12:09 am
kitchen-sink	❌ Build Failed (View Logs)	Web	Apr 20, 2026 at 12:08 am

[NathanFlurry]

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• chore: move rivetkit to task model #4680 👈 (View in Graphite)
• chore: rivetkit to rust #4679
• feat(rivetkit): sqlite vfs v2 #4673
• chore: rename sandbox -> kitchen sink #4671 : 1 other dependent PR (#4672 )
• chore: configure TLS trust roots for rustls clients #4667
• fix(rivetkit): update config to match envoys & remove manager references #4663
• chore(publish): pin docker base image refs #4652
• chore(engine): publish engine bases in ci #4649 : 2 other dependent PRs (#4650 , #4666 )
• chore: lockfile lefthook #4647
• fix(rivetkit): surface native sqlite kv errors to callers #4645
• fix(rivetkit): prevent sleep races during disconnect and db work #4644
• fix(rivetkit): isolate engine envoys and propagate startup failures #4643
• test(rivetkit): remove wasm sqlite-only fixtures and coverage #4642
• chore(sqlite-vfs): remove wasm sqlite packages and workspace wiring #4641
• chore(rivetkit): remove wasm sqlite runtime #4614
• fix(sqlite-native): restore native startup kv preload #4639
• fix(sqlite-native): delete metadata before chunk range #4638
• fix(sqlite-native): keep truncate cache coherent #4637
• fix(sqlite-vfs): use delete range for truncate cleanup #4636
• fix(sqlite-native): restore kv error hook #4635
• perf(sqlite-native): avoid cloning cached read chunks #4634
• perf(sqlite-native): gate kv operation labels #4633
• perf(sqlite-native): reuse read cache for partial writes #4632
• perf(sqlite-native): remove delete file existence probe #4631
• fix(sqlite-native): gate native read cache behind env var #4630
• fix(pegboard): isolate runner config dc lookup failures #4625 : 1 other dependent PR (#4626 )
• docs(pegboard): note runner config upsert split write risk #4624
• fix(pegboard): unpack global runner config keys correctly #4623
• fix(pegboard-gateway): enforce tunnel message state #4622
• fix(pegboard-runner): clear terminal tunnel routes #4621
• fix(pegboard): skip protocol version keys in runner pool backfill #4620
• fix(pegboard): create missing normal runner configs #4619
• fix(epoxy): reuse cached optimistic value #4618
• main

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[claude]

PR Review: chore: move rivetkit to task model (Draft, 3 files changed +345/-1496).

OVERVIEW: Replaces the RivetKit Rust SDK PRD and progress log with a new rivetkit-core Actor Lifecycle task-model PRD. Drops rivetkit, rivetkit-client, serde_cbor, tokio-test from Cargo.lock. No Rust source files modified.

CARGO.LOCK: Clean dependency removals. One concern: rustls-native-certs 0.8.3 is dropped for two packages. CLAUDE.md requires enabling BOTH rustls-tls-native-roots AND rustls-tls-webpki-roots together. Verify the affected crates are not still TLS-dependent (native-only breaks on Distroless/Alpine).

PRD (27 new stories, all passes:false): Well-scoped to rivetkit-core + minimal envoy-client glue only, correctly excluding rivetkit-napi and TS. Each story anchors TS parity to feat/sqlite-vfs-v2 with line numbers. Bounded channel design (US-023) and ActivityDirty coalescing (US-021) are solid fits for the channel model.

Minor concerns in PRD:

1. US-019/US-020 (mutate_state re-entrance): in_on_state_change AtomicBool is checked before taking the write lock, which is a TOCTOU window. Two concurrent mutate_state callers could both read false before either sets it. Set the flag inside the write lock, or use the write lock itself as the re-entrance gate.
2. US-012 (priority 12) references lifecycle_command_inbox_capacity config fields added by US-003 (priority 3). Numeric ordering looks correct but confirm execution order does not swap these.
3. US-027: cargo clippy -- -W warnings is an acceptance criterion. Per CLAUDE.md, fix.sh and auto-format should not run automatically. Ensure the story does not trigger auto-format.

PROGRESS LOG: Truncation of ~500 lines of learnings from prior stories is intentional. Most patterns (BARE key layouts, N-API callback ordering) are already captured in CLAUDE.md.

SUMMARY: Well-scoped planning PR. Verify rustls-native-certs removal does not break TLS for any remaining crates. The in_on_state_change TOCTOU in US-020 is the one design concern worth addressing before implementation.