writeonce/docs/plan/00-kanban.md

Status board — what is done, what is next

The single place to learn where this project stands. Organised in six buckets: stories (the narrative arc), in progress, done, pending, discarded, learnings. Every phase doc carries a matching status banner; this board is the index.

Update this board in the same change that finishes work — move the item to done with what actually landed, set the next in-progress item, and record any rejection in discarded.md with its reason.

Statuses: ✅ done · 🔄 in progress · ⬜ pending · ⏸ parked

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▶ NEXT PLAN

Story iteration 4 — single binary end-to-end. Plan: compiler/plan/2026-08-01-wob-emit-e2e-single-binary.md · Story slice: docs/stories/language-runtime-database/04-single-binary-e2e.md

The bytecode emitter, the three-kind conformance corpus, and woc build. This is the milestone where .wo source becomes a running self-contained binary — compiler front (iteration 3) and VM core (iteration 2) both shipped, so it is unblocked. Its inputs are the four ownership tables owner.ml now produces; dump.ml's format-contract comments are normative for it, including the requirement to coalesce borrow guards per operand.

Two tracks run in this repo. The critical path is the language track: iterations 3 → 4 → 5 → 6 → 7, ending at compile and run log-watcher. The Rust-runtime track is shipped-and-maintained, not advancing.

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Stories

docs/stories/language-runtime-database/ — one language, one runtime, one database, one binary. Twelve iterations, each an unsplittable slice with Given/When/Then acceptance and a pointer to the plan that sequences its tasks. Read one, approve, then the next starts.

#	Iteration	State
1	Principles doc	✅
2	VM core (wovm)	✅
3	Compiler front (woc)	✅ (known gaps below)
4	Single binary end-to-end	🔄 next
5	Language surface	⬜
6	Program mode + stdlib	⬜
7	log-watcher proof	⬜ acceptance
8	Shard-actor runtime	⬜
9	Database engine	⬜
10	HTTP service layer	⬜
11	Fibers	⬜
12	Blue-green deploy	⬜

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In progress

Track	Item	Where
Language	Iteration 4 — emitter, conformance corpus, woc build	plan 3

Nothing else should be started until iteration 4 lands. Off-critical-path work is parked by explicit scope directive (2026-08-08).

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Done

Language track — compiler + VM (OOP track)

Status	Item	Doc	What actually landed
✅	Principles	../00-principles.md	13 principles, each with a why and a link to the doc that enforces it
✅	wovm VM core	plan 1	.wob v1 loader with full static validation, register interpreter (computed-goto + ISO-C fallback), arena with size-class free lists, borrow word, RC + budgeted Bacon–Rajan cycle collector, drop-map trap unwinding, containers, builtins, ICALL, CLI. 13 suites × 2 dispatch flavors + CLI smoke, ASan/UBSan clean
✅	.wob format contract	oop-vm/00-wob-format.md	Normative; twinned with runtime/src/wob.h
✅	woc compiler front	plan 2	Tasks 1–8: dune scaffold, diag (WO-E codes, two-site related errors, ordered dedup), newline-significant lexer at rt parity, declaration + statement/expression parser with skip-on-block and multi-error recovery, typechecker (field kinds, ?T plumbing, W201, E225, E214), MVS ownership pass with the four emitter tables, driver with directory discovery + cross-file programs. 14 + 264 checks
✅	Error catalog	oop-vm/01-error-catalog.md	14 emitted codes + 10 reserved, each with the reason it is not yet emitted
✅	log-watcher .wo sample	../examples/log-watcher/	Eight-file port authored docs-first with its .hx mapping table; compiles for real in iteration 7
✅	Scalar cleanup	discarded.md	Money/SKU/Float and the abstract allowlist removed; abstract flipped adopt → reject

Known gaps carried out of iteration 3 — recorded, not silently owed:

• ?T is plumbed but unenforced. Lexer/token/AST/parser/dump all handle ?T; the semantics do not exist (WO-E211/E212/E213 declared, never emitted — a probe returning ?Int as Int exits 0). Owned by iteration 5, plan 8 Task 6, which is that iteration's first task because it blocks the log-watcher port. See compiler/nullable-types-implementation.md.
• Structural interface satisfaction is not checked (WO-E205 dead), along with type mismatch, bad arity, and unknown-fn (E201/E203/E204) — all named in plan 2 Task 6's own must-fail list. Gaps in shipped work, catalogued as reserved.
• Six further narrowings (W201 heuristic, E225 reach, dead code after return, unresolved-callee drops, RC table ordering, residual b-side role) are listed in the plan-2 SDD ledger and in the affected files' own comments.

Rust runtime track — Stage 2 shipped, maintained

Status	Phase	Doc	Notes
✅	01 crate scaffolding	done/01	15 crates
✅	02 epoll event loop	done/02	runtime/netpoll_epoll.rs
✅	03 hand-rolled HTTP	done/03	+ keep-alive & pipelining
✅	04 tokio/axum cutover	done/04	deps now: anyhow, serde, serde_json, libc
✅	09a thread-per-core	09	scheduler.rs, SO_REUSEPORT, pinned wo-shard-<t> workers
✅	09b sharded engine	09	shard.rs bus; Arc<Mutex<Engine>> deleted; interleaved ids
✅	09c per-shard WAL	09	ack-after-fsync; boot replay; meta shard guard
✅	— keep-alive follow-up	09	reads ×3.4 → 770k/s
✅	— io_uring group commit	09	raw ring; 4.7× durable writes on real disk
✅	16a PG wire client	16	hand-rolled protocol v3, zero crates
✅	16b PG backup mirror	16	async JSONB upserts behind the WAL ack; RAM authoritative
✅	13a class surface	13	class parses, CRUD serves
✅	13b method execution	13	row-scoped txn per call; abort → 409 rollback
✅	— @table + indexed DML	13	secondary indexes, find_by, select Type{…}, REST filters
✅	C proving ground A–F	exploration/c-runtime/00-plan.md	859k reads/s, 618k durable commits/s; found the ack-ordering + fd-ABA bugs the Rust port avoided

Ecommerce sample (verified 2026-06-13): api.rest 17/17 expected statuses pass.

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Pending

Language track — sequenced, on the critical path

#	Item	Plan
5	Haxe-parity language surface — ?T forced handling first, then switch expressions, records, enum payloads, try/catch, statics, using, modules, is, pub(read), #if	plan 8
6	Program mode + systems stdlib — fn main, exit codes, fs/proc/net/time/json	plan 9
7	log-watcher proof — the sample compiles and detects a silent death live	plan 10
8	Shard-actor runtime	plan 4
9	Database engine binding	plan 5
10	HTTP service layer	plan 6
11	Fibers	vision §3, blue-green exploration
12	Blue-green deploy	spec — plan authored after iterations 9–10

Language track — parked until after iteration 12

Recorded 2026-08-08 by scope directive; nothing here lands before the log-watcher proof.

• WO-W201 @gc-suggestion refinement beyond the self-reference heuristic
• WO-E225 broadened to ref/multi/map element types and fn signatures
• ADT container roster adoption (Stack, Queue, Set, Tree, Graph, …) — see the roster in compiler/nullable-types-implementation.md
• Web framework as a .wo library; UI (##ui SSR + live patches); script-based destructive migrations; MCP/agent wrapper over the management plane

Rust runtime track — not advancing while the language track runs

Status	Phase	Doc	Notes
⬜	05 hand-rolled JSON	05	removes serde/serde_json
⬜	06 bespoke error type	06	removes anyhow
⬜	07 inotify content watcher	07	wo dev hot reload
⬜	08 sendfile static assets	08	needed by the parked UI track
⬜	09d cross-shard subscriptions	09	LIVE fan-out; pairs with Stage 3
⬜	09e cross-shard transactions (2PC)	09	needed by fn checkout spanning shards
⬜	09f observability & reshard	09	per-shard metrics, WO_RESHARD
⬜	10–12 storage completion	10, 11, 12	snapshots, compaction, WAL rotation, mmap arena engine
⬜	13c LIVE pricing push · Stage 3 wire layer · 13e at scale	13	replaces the 501 stub
⬜	15a–15e MCP over streamable HTTP	15	15e needs 13c + 09d
⬜	16c–16f typed columns, lossless resync, restore, SCRAM	16

Frontend — parked

Status	Phase	Doc
⏸	13d pricing UI	13
⏸	14 MVC UI implementation (14a–f)	14
⏸	UI exploration track	exploration/ui/00-overview.md

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Discarded

Settled rejections with their reasons live in discarded.md — inheritance, abstract newtypes, Money/SKU/Float, Dynamic/cast/ macro/extern, AOT-to-C, Menhir, shared mutable engine state, external deployer daemon, destructive migrations in v1, and more. Argue against the recorded reason rather than re-opening an entry as new.

Learnings

What attempts taught, shipped or not, in learnings.md — plumbed-is-not-enforced, vacuously-passing goldens, exit-0-with-wrong-output, the malloc-path ASan trick, deferred checks that never reach the runtime, validate-once-at-the-boundary, and reference-implement-in-C-first.