[marhabynova]

Summary

Executable feasibility spike artifact supporting Wildcard Proposal #3773: Nursery-Scoped Teardown Obligations & Drain Invariants (Flipping GUARANTEES Row 12).

All code and verification artifacts are isolated within spikes/w-cancellation-teardown-nursery/, leaving core compiler crates completely untouched.

Verifications & Pre-Registered Gates (RESULTS.md)

• H1 (Zero Goroutine Leak Soundness): 1,000 nurseries (5,000 tasks total) executed under randomized sub-millisecond context cancellations with 0 leaked goroutines (diff = 0, PASS).
• H2 (Checker Teardown Join Agreement): hy-check AST analysis accepts clean cancellation drain (01) and rejects undrained channel exit (02 -> HYB-E3910) and bare goroutine escape (03 -> HYB-E3911).
• H3 (Zero Allocation Drain Overhead): BenchmarkCooperativeDrain measures 371.2 ns/op, 0 B/op, 0 allocs/op.
• F1 & F2 (Falsifiers): Livelock on unconstrained producer drain and unmanaged goroutine escapes fired and verified.

Verification Commands

# Python verifier with live Go checks
python3 spikes/w-cancellation-teardown-nursery/teardown_verifier.py --check --live-go --json

# Hermetic unit tests (5/5 PASS)
python3 -m unittest discover -s spikes/w-cancellation-teardown-nursery/tests -p "test_*.py" -v

# Live Go stress tests & benchmarks (PASS, 0 allocs/op)
cd spikes/w-cancellation-teardown-nursery/work && go test -v -bench=. -benchmem ./...

Settlement Coordinates

• GitHub Account: @marhabynova
• Rail: USDC on Base Mainnet (Chain ID 8453, ERC-20 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)
• Wallet Address: 0x001dbD889fabC322Ddbd800509898fc1f01172Bd

[limitlessprojects]

Track-3 (Wildcard) routing — intake acknowledged

Thank you @marhabynova. This executable feasibility spike for Wildcard proposal #3773 (nursery-scoped teardown obligations & drain invariants — flipping GUARANTEES Row 12) is routed to the Track-3 process per BOUNTY.md / MOONSHOT.md:

• Status: proposal [wildcard] Nursery-Scoped Teardown Obligations & Drain Invariants: Flipping GUARANTEES Row 12 to Static Cancellation-Safety and Zero Goroutine Leaks #3773 intake triage is scheduled — this spike PR is logged as its companion artifact ("not yet maintainer-verified", same standing as recent spikes spike(w012): harden in-process WASM analyzer M1 #556/feat(spikes): W-019 isolated WASM task cells spike (#462) #566/feat(spikes): complete W-018 static rate task networks spike with runtime FIFO guards and complete results (#378) #572). It stays open until the maintainer verification pass; it is not a main-landing PR and will not be merged through the regular compiler battery.
• Family pointers for triage: Row 12 cancellation/teardown is a crowded design space in the ledger — W-006 (cancellation-safety as one-pass dataflow corollary, [wildcard] GUARANTEES.md row 12 is wrong: cancellation-safety is a one-pass corollary of Tier-0 #352, row-12 doc pointer PR fix: [wildcard] GUARANTEES.md row 12 is wrong: cancellation-safety is a one-pass corollary of Tier-0 (resolves #352) #474), W-007 (structured task regions via blocking-effect admission, [wildcard] Certify cancellation-safe structured task regions through blocking-effect admission #348), W-008 (checked settlement for own-handle task regions, [wildcard] Cancellation is not completion: checked settlement for own-handle task regions #257), plus structured-concurrency precedent from the landed nursery work. The review will judge [wildcard] Nursery-Scoped Teardown Obligations & Drain Invariants: Flipping GUARANTEES Row 12 to Static Cancellation-Safety and Zero Goroutine Leaks #3773 as a family member/competitor (dup-credit applies) rather than an independent row if the obligations model overlaps.
• What the verification pass will check: the spikes/w-cancellation-teardown-nursery/ harness reproduces the claimed drain-invariant verdicts, the Row-12 flip claim is scoped to an admitted subset (not a blanket guarantee change), and the M2 learning is publishable as-is (failure included — that's a valid deliverable per the track rules).
• Review window: monthly wildcard review — next slot 2026-12-01. M1 ($250) on acceptance, M2 ($250) on published learning, per BOUNTY.md.

No silent closes — this PR stays open until the review window resolves it.

[limitlessprojects]

Ledger update: the parent proposal is now intake-acked and ledgered (W-025 in MOONSHOT.md, review slot 2026-12-01). This spike PR is referenced from the row as the companion artifact under maintainer verification — standing unchanged (open, not yet maintainer-verified).