Public

Precheck and Signoff

What recorded DRC, precheck, and CoB checks prove, with policy conflicts preserved.

Scope

This page states what the recorded checkers meant and what a pass did or did not prove. The ordered upload, retry, and final-submit procedure belongs on Submission Procedures.

Checker meaning

  • Confirmed fact — 2025-11-03: Precheck was described as running Magic and KLayout DRC, off-grid and angle checks, density checks, and layout-specific checks. It was also intended to replace the included QR-code cell with the correct design ID. Evidence (Discord)
  • Confirmed fact — 2025-11-28: The online platform ran gf180mcu-precheck, including smaller checks plus KLayout and Magic DRC. Evidence (Discord)
  • Decision — 2026-03-27: Passing DRC was stated to be strictly required for tapeout. There was no DRC waiver system. Evidence (Discord)
  • Decision with narrow scope — 2025-12-14: Magic DRC became non-blocking because imported non-Magic layouts could give false positives. Users were still told to inspect every Magic violation and report any real problem not found by KLayout. Evidence (Discord)
  • Confirmed decision — 2026-03-16: KLayout was the trusted tapeout DRC result; Magic DRC was not required because it could report false positives. Evidence (Discord)

Conflict resolved

“Magic DRC is non-blocking” does not mean “DRC is optional.” The first statement applies to one checker whose import path could give false positives. The 2026-03-16 guidance assigns tapeout DRC authority to KLayout, while the 2026-03-27 decision says overall DRC pass is mandatory and cannot be waived. Record the checker, deck, version, and exact violation when interpreting a result. Magic decision (Discord) KLayout decision (Discord) No-waiver decision (Discord)

CoB checks

  • Confirmed fact — 2026-06-18: Precheck 1.7.0 added a comparison between CoB pad positions and a golden mask. Template 1.5.3 fixed a 0.5 um north/south pad offset. Evidence (Discord)
  • Confirmed statement — 2026-08-13, live-search capture: The precheck was said to enforce CoB pad coordinates and DRC-clean layout. No canonical Discord URL was captured for this search result. Evidence

What a pass does not prove

  • A pass from one checker does not prove that another checker has no findings. The recorded policy kept manual review of Magic findings even when Magic was non-blocking. Evidence (Discord)
  • A historical precheck pass does not prove that a current submission uses the same decks, PDK, image, or platform logic. The online checker set is dated 2025-11-28, while the template and precheck changed in June 2026. Old platform evidence (Discord) New precheck evidence (Discord)

Proposals and open questions

  • Proposal, not confirmed: On 2025-11-28 an admin precheck override was promised during test-platform work. The archive does not prove that it became production policy. It does not override the later no-waiver decision. Evidence (Discord)
  • Open question: The current authoritative deck versions and current online checker set must be checked on the live submission system before a run-specific signoff statement is published. The archive shows that checker behavior changed over time. Evidence (Discord)

Sources

  • 1434849326584037460 — 2025-11-03T10:18:57.669+00:00 — Leo Moser (mole99) (@mole99) — intended precheck coverage and project-ID handling. Evidence (Discord)
  • 1443909361427681351 — 2025-11-28T10:20:18.303+00:00 — Leo Moser (mole99) (@mole99) — online gf180mcu-precheck checker set. Evidence (Discord)
  • 1449816127919100115 — 2025-12-14T17:31:41.177+00:00 — Leo Moser (mole99) (@mole99) — Magic DRC non-blocking decision and review duty. Evidence (Discord)
  • 1483013259635327016 — 2026-03-16T08:05:14.151+00:00 — Leo Moser (mole99) (@mole99) — KLayout tapeout authority and Magic DRC boundary. Evidence (Discord)
  • 1486979241148158012 — 2026-03-27T06:44:37.828+00:00 — Tim 'mithro' Ansell (@mithro_) — strict DRC requirement and no waiver. Evidence (Discord)
  • 1517130928248586290 — 2026-06-18T11:36:40.224+00:00 — Leo Moser (mole99) (@mole99) — CoB offset and golden-mask checks. Evidence (Discord)
  • 1537441624102141982 — 2026-08-13T12:44:07.470Z — Leo Moser (mole99) — CoB coordinate and DRC statement. Live-search capture; canonical Discord URL unavailable. Evidence
  • 1444092802379288697 — 2025-11-28T22:29:14.034+00:00 — Tim 'mithro' Ansell (@mithro_) — proposed admin override. Evidence (Discord)