[PerchAnton]

Working result

BreakFree Sheets now runs as an independent native Rust desktop application. Model, restricted formula parser, dependency graph, decimal calculation, history, persistence, Office CLI and GUI are all Rust. The earlier Python implementation is preserved as a conformance archive and is not a build/runtime dependency.

The virtualized painted grid, local File page, compact icon ribbon with the requested tabs/Home groups, name box, shared-source formula bar, selection/ranges, sheet area, real scrollbars and status/zoom are connected to the tested engine. A1=2, B1=3, C1==A1+B1 gives 5; A1=4 gives 7. Grid/formula-bar editing, undo/redo and save/reopen continue to recalculate. Unsupported formatting, fill, sorting, functions and additional sheets are visibly disabled.

Home now uses original geometric command icons, consistent group baselines and explicit stored cell types. The name/formula fields, selected headers, sheet tabs and status zoom are refined. File provides real New/Open/Save/Save As/Close commands with the existing unsaved-entry protection. A horizontal ribbon scrollbar gets reserved height at narrow logical widths. View provides real Gridlines/Headings/Formula Bar and zoom controls. Ctrl+F1, tab double click or the chevron collapses commands; clicking a collapsed tab opens them persistently. Hiding the formula bar transfers a pending shared draft to inline editing. The corner selects the bounded whole sheet for real Clear/Undo.

The owner decisions (Rust, desktop Excel 2024 for Windows as reference, own BreakFree Sheets brand) are recorded in AGENTS.md and ADR 0003. The approved transparent dedicated Sheets icon is adopted from e7de5a9. The toolkit is egui/eframe, with native winit/OpenGL; no WebView, Electron or HTML/JS grid. No project license is selected.

Verification

• cargo test --locked: 39 passing tests (20 engine/files/contract and 19 native egui component/event tests).
• 35 frozen synthetic old-engine scenarios pass in Rust without Python.
• Deep 2600-cell chains, direct/indirect cycles, precedence/unary minus, decimal half-even/bounds, typed identifiers, undo/redo, malformed/foreign/future/duplicate files and injected partial-write/flush/replace failures covered.
• Native pointer/key tests cover the required grid/formula-bar loop, range selection, resizing, scrolling, unsaved prompts, typed clipboard, ribbon actions, File-page draft protection and narrow-width Home/View caption visibility. New tests cover hidden-header coordinates, draft handoff, collapse, actual grid-stroke visibility, unchanged saved bytes and whole-sheet Clear/Undo.
• fmt and Clippy with all targets/features passed; optimized macOS build and isolated-binary headless commands passed.
• Six alpha.3 native macOS framebuffer captures inspected: Home at 1.0/1.25/1.5, View at 1.0/1.5 and collapsed ribbon at 1.0. Earlier alpha.1 File/range evidence retains its version. These are diagnostic UI scales, not Windows DPI evidence; see UI_SPEC.
• Dependency/font notices and exact-source provenance retained; redistribution audit remains a release gate.
• New native Windows/macOS/Linux CI and Linux/Xvfb capture workflow are defined. Commit-specific server results are recorded separately in PROJECT_LOG.md.

Scope and acceptance gaps

One sheet, A1–Z100; restricted arithmetic and A1 references; 28-digit decimal with explicit half-even rounding, not a financial-accuracy guarantee. Clipboard supports one typed cell with literal formula references. Row/column dimensions and grid zoom are view state, not persisted in native v1. No CSV/XLSX or Excel compatibility claim.

Exact Excel 2024 Windows build/reference screenshots and real Windows 100%, 125%, 150% DPI measurements are unavailable here. UI_SPEC records implemented geometry, differences, documentary sources and the remaining matched-capture procedure. Interactive Windows/Linux, IME/accessibility and installer/power-loss checks remain open.

All four Office CLI commands work independently. The local temporary v1 snapshot is retained; upstream cfaaf419 has no contracts/ADRs, so reconciliation is still unverified.

The roadmap preserves the later sequence. Project journal updates remain separate commits. Draft for review only: no merge, release or automatic participant replies.

Versioning

Current development candidate: 0.1.0-alpha.3, pending exact-number agreement. The owner agreed to 0.1.0-alpha.2 on 2026-10-16; that is not release approval. Each coherent changeset increments the prerelease counter and adds a dated CHANGELOG.md entry, including docs/tests/configuration. Related verification and journal commits share the same number.

Cargo metadata, the root lockfile entry, CLI and Office JSON fixture agree on alpha.3. Protocol and native content versions remain 1; no calculation/dependency migration was needed. All initial alpha/beta/rc builds use the 0.1.0 base; the first stable release is 0.2.0. Candidate preparation, exact-number agreement, channel promotion and publication remain distinct. See VERSIONING and ADR 0004. No tag, merge or product release is created.