writeonce/docs/plan/discarded.md

Discarded — settled rejections

Decisions that were considered and rejected, with the reason. This file exists so a settled question is not re-proposed. If you want to revisit an entry, argue against the reason recorded here — do not re-open it as if it were new.

Status board: 00-status.md · Doctrine: ../00-principles.md

Language surface

Rejected	Date	Reason
Inheritance — extends, super, override, implements	plan 13 / OOP spec	No hierarchies, ever. Is-a is a tagged union, has-a is composition, polymorphism is structural interfaces. Hierarchies fossilize early guesses and make dispatch, ownership, and diagnostics all harder. Principle 4.
abstract newtypes (abstract Money = Int)	2026-08-10	Flipped adopt → reject in the systems-track verdict table. A distinct scalar type adds a conversion surface without buying safety this language needs; domain scalars stay plain Int/Text. The Money/SKU stopgap allowlist that stood in for the unbuilt feature proved the cost was real. Haxe-parity's abstract+is task was deleted outright — abstract rejected here, is cut for zero uses in the driving workload.
Money, SKU as language types	2026-08-10	Removed from builtin_scalars and from the abstract allowlist. Money → Int (minor units), SKU → Text everywhere.
Float as a builtin scalar	2026-08-10	Phantom: it was in builtin_scalars and documented as f64, but token.ml has no float literal and wob.h has no float kind — ratio: Float typechecked while no Float value could ever be written or represented. Re-add only when literals and a wob float kind land together.
Dynamic / untyped	systems-track spec	Static typing is the untagged-register VM's foundation. Typed json.decode … as T -> ?T covers the real use. Principle 13.
cast	systems-track spec	No unsafe casts. Conversions are typed; as exists only in the decode-target position.
macro	systems-track spec	Kills the fast-compile promise. Codegen belongs to wo gen tooling.
extern / FFI	systems-track spec	One FFI hole voids the whole memory-safety story. Capabilities are audited typed builtins. Principle 10.
operator overloading, overload	systems-track spec	One name, one signature. Keeps dispatch and diagnostics simple.
inline functions	systems-track spec	Optimization is the compiler's job. const compile-time values are adopted; inline functions are not.
User-definable generic containers	OOP spec §3	multi and map are runtime-provided native classes implemented in C. The VM picks the backing data structure; the language exposes only the ADT's operations.

Compiler / VM architecture

Rejected	Reason
AOT compilation to C	Kills hot reload and makes builds slow. A register bytecode interpreter with computed-goto dispatch ships first; a JIT stays possible later.
Approach B — "Lua-shaped minimal" VM	Defers the project's core risk (the hybrid borrow VM) and adds a Menhir dependency.
Approach C — "Rust-lite static regions"	Research-grade complexity; recreates exactly the Rust ergonomics pain that mutable value semantics exists to avoid.
Menhir, ppx, any opam package	OCaml stdlib only; handwritten lexer and recursive-descent parser. dune is a build runner, nothing more.
First-class borrows (storable, returnable)	Second-class borrows (Hylo/Val mutable value semantics) eliminate full lifetime inference — the compiler needs only per-function flow analysis. Long-lived links go through ref T ids or @gc.
Empty-list stub for is_abstract_type	2026-08-10: a function that can never return true is dead code. Deleted outright instead.

Runtime / deployment

Rejected	Reason
Arc<Mutex<Engine>> / any shared mutable engine state	Thread-per-core shards each own their engine, heap, and event loop; cross-shard work is an ownership-moving message send. Principle 5.
External deployer daemon	Violates two-VMs-in-one-runtime and splits the data plane. The management plane is a runtime module with a thin CLI.
Self-hosted .wo deploy logic	Bootstrap problem — the deploy path cannot be written in the language whose deployment it implements. Recorded as a much-later possibility.
Script-based / destructive schema migrations (v1)	Additive-only auto-diff is what makes rollback unconditional: the previous version ignores fields and classes it never knew. Destructive changes reject at propose time.
Portability abstractions over Linux	Targeting one kernel lets the runtime use its sharpest primitives directly instead of the lowest common denominator. Principle 9.
Mirrors on the commit path	The Postgres mirror is a reconstructible backup. RAM is authoritative; reads and acks never depend on it. Principle 7.

Process / docs

Rejected	Reason
Per-example principle.md files	2026-08-08: one canonical repo-level docs/00-principles.md instead; examples link to it.
Minimal 3-file log-watcher sample	Breaks the file-for-file .hx → .wo mapping and leaves the "could not express" column unproven — which is the sample's entire acceptance criterion.
Raw code in plan documents	Plans carry concept, reason, and required behavior in words; the executor writes the code.
##ui / .htmlx LiveView frontend track	2026-08-17: removed the 9-doc exploration/ui/ design set, the 14-mvc-ui-implementation plan, and the ui-htmlx-live plan. All were built on the non-advancing Rust runtime (.dev/reference/crates/writeonce-viewx, cargo run, WebSocket live-patches) and contradict the current woc/wovm direction. The 13d pricing-UI row went with them. Revisit only if a UI story is re-opened on the woc/wovm stack.
Old-runtime "front door" + v1 design docs	2026-08-17: removed writeonce-pl.md, runtime/wo-language.md, future-scope/ai-agents-content-management.md, the numbered v1 set 02-recovery/03-data/04-ui/05-datalayer/06-markdown-render/07-ssl, and runtime/database/05-go-sdk.md. They pitched the old Rust wo runtime (REST + LiveView + SQL/Cypher) as the current language and contradicted the shipped woc/wovm toolchain.
The 2026-08-01 shard-actor plan (epoll-based)	2026-08-21: superpowers/plans/2026-08-01-shard-actor-vm-runtime.md marked discarded, file kept as reference. Superseded by the arc plan of record (2026-08-20-shard-fiber-arc.md, stages 1+2 landed): io_uring is a MUST and the epoll-based approach is discarded — the old plan's "epoll now / io_uring later" premise is inverted, and its substrate (runtime/wo-rt.c) left with the Rust track 2026-08-18.
The entire Rust wo runtime track	2026-08-18: removed crates/ (the Stage-2 Rust runtime), Cargo.toml/Cargo.lock, prototypes/ (wo-rt-c stale duplicate + wo-db C++ ref), the rt-c-* justfile recipes, the Rust engineering plans (docs/plan/05..16, docs/plan/done/), and docs/runtime/ (the old runtime overview + 7-phase DB design series + async/fibers/gc/surreal essays). It was the prior, abandoned architecture — fully independent of the woc/wovm stack. Master now reflects only the current single-language project; the removed track lives in git history if ever needed as reference. Kept: the syscall/postgres/assembly/c-runtime exploration studies (they fed the current C runtime) and the discarded/learnings registers.

Successor map for the removed Rust-era plan paths

Added 2026-08-26. The exploration studies under exploration/ were written against the old flat docs/plan/NN-*.md numbering and the docs/runtime/database/ tree, both removed with the Rust track above. Those 48 dangling links were de-linked, not re-pointed — their prose names the retired plan by number ("plan 09a", "plan 11"), so aiming them at a story would have made the sentence lie. The studies still read correctly; the names are now plain text. This table is where a reader goes to find what took each one's place.

Retired path	What carries that work now
09-concurrency-scaleout.md	08-shard-actor-runtime.md + 11-fibers.md — the arc, landed 2026-08-21
10-storage-foundations.md, 11-wal-and-recovery.md	09-database-engine.md (typed WAL + replay) and 22-durability-throughput-scale.md (the measurements)
12-engine-disk-cutover.md	Nothing — RAM stays authoritative by doctrine (principle 7). The disk story is the WAL; reclamation is databasev2 3, WAL checkpoint
13-class-model-live-pricing.md	09b-table-relations-query.md — @table, ref/backlink, the compiler-checked query surface
07-inotify-content-watcher.md	07-logwatcher-proof.md — the log-watcher sample polls via fs.stat; inotify was never surfaced as a builtin
08-sendfile-static-assets.md	Nothing. sendfile is not exposed; static assets are served as Text through net.write
15-mcp-streamable-http.md	28-skillhost-host-workload.md — MCP transport is that story's Blocker B
16-postgres-mirror.md	Nothing — the mirror-is-backup doctrine holds, but no iteration owns it and there are no outbound sockets to reach a mirror with (refine/38)
02-event-loop-epoll.md, 03-hand-rolled-http.md	runtime/src/park.c (io_uring with an epoll fallback) and the .wo framework porch
04-cutover-remove-tokio-axum.md	Completed by the Rust-track removal itself — nothing left to cut over
runtime/database/03-inmemory-engine.md	database/src/CODE-LOGIC.md + plan/oop-vm/04-db-binding.md
runtime/database/02-wo-language.md	docs/guides/language-surface.md
runtime/database/07-wo-seg-migration.md	Nothing — segment migration was a Rust-engine concept with no analogue here
prototypes/wo-db/ (C++ query-layer ref)	Removed with the Rust track. The query layer lives in compiler/src/emit.ml, lowered to engine builtins
exploration/linux/07-splice.md	Never written. Slot 07 is 07-io_uring.md