docs: sync README with Monterey floor, M10, wiki, and packaging

Requirements were still Xcode 15.4 / Swift 6. Point the product
at the user wiki, record host-arch tests, the dmgbuild venv, and
the current develop-first git workflow.

.gitea/workflows/macos.yml

@@ -30,19 +30,26 @@ jobs:
           fi
           echo "$line"
 
+      # Tag pushes whose name contains "prerelease" skip the test build and both
+      # test legs: they exist to package a build already validated elsewhere.
+      # The job still succeeds quickly so `package`'s `needs:` stays satisfied.
       # Homebrew's xcodegen formula requires Xcode 15.3, which cannot be
       # installed on macOS 12 (#109). The script installs a pinned
-      # prebuilt release instead.
+      # prebuilt release instead. dmgbuild is not installed here — the
+      # test job does not package (#95).
       - name: Ensure host tools
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: scripts/ensure-host-tools.sh
 
       - name: Generate Xcode project
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: xcodegen generate --spec project.yml
 
       # Tests only ever run on the runner's own architecture; build
       # just that slice. Packaging (scripts/package-release.sh) still
       # produces the universal Release binary.
       - name: Build for testing (host arch)
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: |
           xcodebuild build-for-testing \
             -scheme ICCery \
@@ -60,6 +67,7 @@ jobs:
       # launch (run 31992) — so sign every embedded copy once the build is
       # done (embed steps run after any build script phase) (#119).
       - name: Sign package product frameworks
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: |
           find "$DERIVED/Build/Products/Debug" -depth -name '*_PackageProduct.framework' -print0 \
             | while IFS= read -r -d '' fw; do
@@ -68,6 +76,7 @@ jobs:
               done
 
       - name: Test unit (ICCeryCoreTests)
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: |
           XCTESTRUN="$(find "$DERIVED" -name 'ICCery*.xctestrun' | head -n 1)"
           if [ -z "$XCTESTRUN" ] || [ ! -f "$XCTESTRUN" ]; then
@@ -90,6 +99,7 @@ jobs:
       # tag packaging can proceed. Real XCTest assertion failures
       # still fail the job.
       - name: Test UI (ICCeryUITests)
+        if: "!(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: |
           set -o pipefail
           XCTESTRUN="$(find "$DERIVED" -name 'ICCery*.xctestrun' | head -n 1)"
@@ -154,7 +164,7 @@ jobs:
       # xcresult on failure — upload it so UI failures can be triaged
       # without access to the runner (#126).
       - name: Prepare Node CA bundle (failure path)
-        if: failure()
+        if: "failure() && !(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         run: |
           NODE_CA_FILE="/tmp/macos-ca-bundle.pem"
           security find-certificate -a -p \
@@ -166,7 +176,7 @@ jobs:
           fi
 
       - name: Upload UI test xcresult
-        if: failure()
+        if: "failure() && !(startsWith(github.ref, 'refs/tags/') && contains(github.ref_name, 'prerelease'))"
         uses: actions/upload-artifact@v3
         env:
           NODE_EXTRA_CA_CERTS: /tmp/macos-ca-bundle.pem
@@ -184,8 +194,10 @@ jobs:
 
       # scripts/package-release.sh runs `xcodegen generate` and dmgbuild;
       # see build-and-test for why brew is not used on macOS 12 (#109).
+      # INSTALL_DMGBUILD isolates dmgbuild in build/.venv-dmgbuild so
+      # the test job never pip-installs it (#95).
       - name: Ensure host tools
-        run: scripts/ensure-host-tools.sh
+        run: INSTALL_DMGBUILD=1 scripts/ensure-host-tools.sh
 
       - name: Package release
         run: scripts/package-release.sh

README.md

@@ -1,45 +1,75 @@
 # ICCery
 
-Native macOS frontend for printer ICC/ICM profiling. ICCery walks a user from chart generation through measurement, `colprof`, verification, and ColorSync install. It is **not** a colour engine.
+Native macOS frontend for printer ICC/ICM profiling. ICCery walks a user from
+chart generation through measurement, `colprof`, verification, and ColorSync
+install. It is **not** a colour engine.
 
-All measurement, chart generation, and profile mathematics live in the [Gronod ArgyllCMS 3.5.0 fork](https://git.i3omb.com/gronod/argyllcms), spawned as AGPLv3 child processes. The GUI never `dlopen`s or links Argyll.
+**End-user guide:** the [repository wiki](https://git.i3omb.com/gronod/iccery-v2-mac/wiki)
+covers every screen (Getting Started through Troubleshooting). This README is
+for building, packaging, and contributing.
+
+All measurement, chart generation, and profile mathematics live in the
+[Gronod ArgyllCMS 3.5.0 fork](https://git.i3omb.com/gronod/argyllcms), spawned
+as AGPLv3 child processes. The GUI never `dlopen`s or links Argyll.
 
 | | |
 |---|---|
 | Product | ICCery v2 for macOS |
 | Bundle | `com.gronod.iccery2` |
+| Version | 2.0.0 |
 | Floor | macOS 12.0 Monterey, universal `arm64` + `x86_64` |
+| Toolchain | Xcode 14.2 / Swift 5.7 (project `SWIFT_VERSION` is 5.0) |
+| CI | Gitea Actions `macos-12` runner |
 | Default branch | `develop` |
-| M6 | Stage 0 calibration, CGATS import, SceneKit gamut viewer, packaging — shipped on `develop` |
+| M6 | Stage 0 calibration, CGATS import, SceneKit gamut viewer, packaging — shipped |
-| M7 | Pre-UAT hardening & baseline consolidation — shipped on `develop` |
+| M7 | Pre-UAT hardening — shipped |
-| M8 | Deduplication/consolidation contracts & UAT-ready hardening (#79–#86) — shipped on `develop` |
+| M8 | Deduplication contracts & UAT-ready hardening (#79–#86) — shipped |
-| M9 | macOS 12 / Xcode 14.2 retarget — shipped on `develop` (PR #145) |
+| M9 | macOS 12 / Xcode 14.2 retarget (PR #145) — shipped |
-| M10 | Studio workflow (#146–#149) — in flight on `milestone/m10-studio` |
+| M10 | Studio workflow: gamut compare (#147), Spot Read (#148), project files (#149) shipped on `develop`; media library (#146) is in the tree, issue still open |
 | Licence | Proprietary source in [`LICENCE.md`](LICENCE.md); bundled Argyll sidecars remain AGPLv3 |
 
 ## What it does
 
 The wizard is artefact-gated:
 
-1. **Stage 0** — printer calibration: `printcal` / `applycal` session, `CAL_` basename restore
+1. **Stage 1** — `targen` → `.ti1`
-2. **Stage 1** — `targen` → `.ti1`
+2. **Stage 2** — `printtarg` → `.ti2` + TIFF, unmanaged `lp` spool, bound `NSPrintPanel`
-3. **Stage 2** — `printtarg` → `.ti2` + TIFF, unmanaged `lp` spool, bound `NSPrintPanel`
+3. **Stage 3** — `instlist` + streaming `chartread` (strip / XY / handheld) → `.ti3`, multi-pass average, CIEDE2000
-4. **Stage 3** — `instlist` + streaming `chartread` (strip / XY / handheld) → `.ti3`, multi-pass average, CIEDE2000
+4. **Stage 4** — `colprof` → `.icc` / `.icm`; optional `applycal`; `iccgamut` next to the profile
-5. **Stage 4** — `colprof` → `.icc` / `.icm`; optional `applycal`; `iccgamut` next to the profile
+5. **Stage 5** — `profcheck`, verification history, ColorSync user/system install
-6. **Stage 5** — `profcheck`, verification history, ColorSync user/system install
 
-Plus CGATS dataset import (`.ti3` / `.txt` / `.cgats` / `.csv`), SceneKit gamut preview with sRGB overlay, and signed `.dmg` packaging.
+Plus:
 
-**Not this product:** display calibration (`dispwin` / `dispread`), i18n, Windows/Linux print trees, in-process Argyll, App Sandbox.
+- **Calibrate Printer** — optional `printcal` / `applycal` session under a `CAL_` basename
+- **CGATS import** — `.ti3` / `.txt` / `.cgats` / `.csv`
+- **Media recipes and presets** — printer + paper + ink bound to a preset and optional `.cal`
+- **Spot Read** — live one-patch Lab/XYZ from the instrument
+- **Project files** — `.icceryproj` bookmark over folder, basename, recipe, last ΔE
+- **Gamut viewer** — SceneKit Lab hull, sRGB overlay, second-profile compare, click-inspect
+- **Settings** — default instrument, ΔE good/warning cutoffs, install location, logging
+- Signed `.dmg` packaging with a HiDPI Finder background (Monterey through Sonoma)
+
+**Not this product:** display calibration (`dispwin` / `dispread`), i18n,
+Windows/Linux print trees, in-process Argyll, App Sandbox.
 
 ## Requirements
 
-- macOS 14+
+To **run** a packaged build:
-- Xcode 15.4+ with the macOS 14 SDK and Swift 6.0
-- [XcodeGen](https://github.com/yonaskolb/XcodeGen)
-- Network once, to fetch Argyll sidecars
 
-App Sandbox is **off**. Hardened Runtime is **on**. Entitlements live in `ICCery.entitlements`.
+- macOS 12.0 Monterey or later (Intel or Apple silicon)
+
+To **build** on the supported CI/host floor:
+
+- macOS 12 with **Xcode 14.2** (macOS 12 SDK, Swift 5.7)
+- [XcodeGen](https://github.com/yonaskolb/XcodeGen) **2.38.0** (Homebrew’s current
+  formula needs Xcode 15.3; CI installs the pinned zip via
+  `scripts/ensure-host-tools.sh`)
+- Network once, to fetch Argyll sidecars
+- For DMGs: Python 3.9+ and `dmgbuild==1.6.7` in `build/.venv-dmgbuild`
+  (`INSTALL_DMGBUILD=1 scripts/ensure-host-tools.sh`)
+
+App Sandbox is **off**. Hardened Runtime is **on**. Entitlements live in
+`ICCery.entitlements`.
 
 ## Build
 
@@ -49,7 +79,7 @@ cd iccery-v2-mac
 git checkout develop
 
 make fetch-argyll          # Vendor/Argyll/macos-universal/, ad-hoc signed
-make test                  # xcodegen + xcodebuild build test
+make test                  # xcodegen + xcodebuild build test (host arch)
 make universal             # ARCHS='arm64 x86_64' ONLY_ACTIVE_ARCH=NO
 ```
 
@@ -62,9 +92,14 @@ xcodebuild test -scheme ICCery \
   ARCHS="$(uname -m)"
 ```
 
-`project.yml` sets `ARCHS: "$(ARCHS_STANDARD)"`, so a plain `xcodebuild test` (and `make test`) builds universal; the `ARCHS="$(uname -m)"` override narrows it to the host slice.
+`project.yml` sets `ARCHS: "$(ARCHS_STANDARD)"`. CI and `make test` override
+that with `ARCHS="$(uname -m)"` so unit/UI tests build the host slice only.
+Fat binaries are `make universal` / `scripts/package-release.sh`.
 
-Sidecars are **not** in git. `scripts/fetch-argyll.sh` pulls the latest (or `ARGYLL_RELEASE_TAG`) macOS-universal release from `gronod/argyllcms`, extracts to `Vendor/Argyll/macos-universal/`, ad-hoc signs every Mach-O, and fails if `codesign -dvv` or the `instlist` marker is missing.
+Sidecars are **not** in git. `scripts/fetch-argyll.sh` pulls the latest (or
+`ARGYLL_RELEASE_TAG`) macOS-universal release from `gronod/argyllcms`, extracts
+to `Vendor/Argyll/macos-universal/`, ad-hoc signs every Mach-O, and fails if
+`codesign -dvv` or the `instlist` marker is missing.
 
 ```bash
 # optional
@@ -74,9 +109,11 @@ export ARGYLL_RELEASE_TAG=…    # default: latest
 export GITEA_TOKEN=…           # private releases
 ```
 
-`make clean` drops `ICCery.xcodeproj`, `DerivedData`, and `Packages/ICCeryCore/.build`.
+`make clean` drops `ICCery.xcodeproj`, `DerivedData`, and
+`Packages/ICCeryCore/.build`.
 
-Do not open the generated xcodeproj as the source of truth. Edit `project.yml` and regenerate.
+Do not open the generated xcodeproj as the source of truth. Edit `project.yml`
+and regenerate.
 
 ## Release packaging
 
@@ -84,11 +121,20 @@ Do not open the generated xcodeproj as the source of truth. Edit `project.yml` a
 scripts/package-release.sh    # fetch → sign → universal build → verify → DMG
 ```
 
-The script builds with a fixed derived data path (`build/DerivedData`),
+The script builds with a fixed derived data path (`build/DerivedData`), locates
-locates `Release/ICCery.app` from it, signs the bundle, recursively verifies
+`Release/ICCery.app` from it, signs the bundle, recursively verifies every
-every bundled Mach-O sidecar (`scripts/verify-sidecar-signatures.sh`), and
+bundled Mach-O sidecar (`scripts/verify-sidecar-signatures.sh`), builds a
-writes `ICCery-${VERSION}-${BUILD_NUM}.dmg` via `dmgbuild`. Sidecars stay
+HiDPI TIFF from `Resources/dmg-background.png` (+ `@2x`) via `tiffutil`, and
-ad-hoc signed inside the bundle — the app is never `codesign --deep`ed.
+writes `ICCery-${VERSION}-${BUILD_NUM}.dmg` with `dmgbuild==1.6.7`.
+
+Sidecars stay ad-hoc signed inside the bundle — the app is never
+`codesign --deep`ed.
+
+`dmgbuild` is **not** a test-job dependency. The package job sets
+`INSTALL_DMGBUILD=1` so `scripts/ensure-host-tools.sh` creates
+`build/.venv-dmgbuild`. On the Monterey runner (Python 3.9) that install uses
+`PIP_IGNORE_REQUIRES_PYTHON=1` and pins `pip>=24.3,<26.1` (pip 26.1+ needs
+3.10). Missing background art is a hard fail (#95).
 
 Environment variables read by the pipeline:
 
@@ -110,30 +156,47 @@ Resources/                 assets; Argyll reference files (not the tools)
 Vendor/Argyll/             fetched sidecars (gitignored)
 Tests/ICCeryCoreTests/     argv goldens, parsers, stores
 Tests/ICCeryUITests/       fixture / mock-binary UI tests
+scripts/ensure-host-tools.sh
 scripts/fetch-argyll.sh
+scripts/package-release.sh
 docs/                      functional spec + v2 ticket plan
 ```
 
-`ICCeryPrintKit` (issue #16, Quartz / AirPrint / TargetPrint) is v2.1 and is not in this tree.
+`ICCeryPrintKit` (issue #16, Quartz / AirPrint / TargetPrint) is v2.1 and is
+not in this tree.
 
 ## Architecture
 
-- **Spawn, never link.** Tools resolve through `BinaryResolver` inside the bundle / `Vendor` tree. `$PATH` is not searched. `ARGYLL_NOT_INTERACTIVE=1` is always set.
+- **Spawn, never link.** Tools resolve through `BinaryResolver` inside the
-- **`ProcessManager` actor** owns child lifetime. Streaming tools (`chartread`, `printcal`, etc.) use the event bus; one-shot tools use `runCaptured`. Exclusive `ProcessID` leases. Quit path: `q\n`, ~500 ms, kill; `killAll` on terminate.
+  bundle / `Vendor` tree. `$PATH` is not searched. `ARGYLL_NOT_INTERACTIVE=1`
-- **Argv builders** in ICCeryCore (`TargenArgs`, `PrinttargArgs`, `ChartreadArgs`, `ColprofArgs`, `ApplycalArgs`, `IccgamutArgs`, `ProfcheckArgs`, `LpArgs`, …). UI must not concatenate flags.
+  is always set.
-- **Atomic artefacts.** Writes go to `*.tmp` then `replaceItemAt`. `applycal` must not replace the input profile on cancel or non-zero exit.
+- **`ProcessManager` actor** owns child lifetime. Streaming tools
-- **Concurrency.** View models are `@MainActor`. No blocking I/O on the main actor. SwiftUI `@Observable` for new state.
+  (`chartread`, `printtarg`, `colprof`, …) use the event bus; one-shot tools
-- **Print.** Unmanaged `lp` with ColorSync suppression (`AP_ColorMatchingMode` / `AP.ColorMatchingMode`). Captured `NSPrintPanel` options win over derived CUPS keys. Never `lp -o raw`.
+  (`printcal`, `applycal`, CUPS) use `runCaptured`. Exclusive `ProcessID`
+  leases. Quit path: `q\n`, ~500 ms, kill; `killAll` on terminate.
+- **Argv builders** in ICCeryCore (`TargenArgs`, `PrinttargArgs`,
+  `ChartreadArgs`, `ColprofArgs`, `ApplycalArgs`, `IccgamutArgs`,
+  `ProfcheckArgs`, `LpArgs`, `SpotReadArgs`, …). UI must not concatenate flags.
+- **Atomic artefacts.** Writes go to `*.tmp` then `replaceItemAt`. `applycal`
+  must not replace the input profile on cancel or non-zero exit.
+- **Concurrency.** View models are `@MainActor`. No blocking I/O on the main
+  actor. Swift 5.7 / macOS 12: `ObservableObject`, not Observation
+  `@Observable`.
+- **Print.** Unmanaged `lp` with ColorSync suppression
+  (`AP_ColorMatchingMode` / `AP.ColorMatchingMode`). Captured `NSPrintPanel`
+  options win over derived CUPS keys. Never `lp -o raw`.
+- **SwiftUI ViewBuilder.** Xcode 14.2 / Swift 5.7 still has the ten-child
+  limit. Split large `VStack`/`Group` trees (#146).
 
 ## Tests
 
 ```bash
-# full suite (host arch)
+# full suite (host arch) — same as CI
 xcodebuild test -scheme ICCery \
   -destination 'platform=macOS' \
   ARCHS="$(uname -m)"
 
-# to compile-check both slices instead:
+# fat compile-check (not the default test path):
 #   ARCHS='arm64 x86_64' ONLY_ACTIVE_ARCH=NO
 
 # examples
@@ -143,9 +206,20 @@ xcodebuild test -scheme ICCery -destination 'platform=macOS' \
   -only-testing:ICCeryUITests/Milestone5UITests
 ```
 
-UI tests need an unlocked console (`IOConsoleLocked=false`). Mock Argyll / CUPS fixtures live under the test bundles; they must not be treated as proof that a real `.gam` / `.icc` was extracted.
+CI (`.gitea/workflows/macos.yml`) runs `build-and-test` then `package` on
+`develop` and on `v*` tags. Tags whose name contains `prerelease` skip the
+test job and still package. `pull_request` is wired for **`develop` only**.
 
-Hardware gates (real instrument, real printer, Gatekeeper-open `.dmg`) are manual and block release, not compile.
+UI tests need an unlocked console (`IOConsoleLocked=false`). Mock Argyll /
+CUPS fixtures live under the test bundles; they must not be treated as proof
+that a real `.gam` / `.icc` was extracted.
+
+Hardware gates (real instrument, real printer, Gatekeeper-open `.dmg`) are
+manual and block release, not compile.
+
+`ArgyllRunnerPrinttargTests.testSuccess` can flake if streaming stdout is
+dropped on a fast mock exit; that is a `ProcessManager` drain race, not a
+missing fixture.
 
 ## Instruments
 
@@ -156,11 +230,18 @@ Detected via bundled `instlist`:
 - SpyderPrint (`p3`)
 - SpectroScan (`SS`)
 - DTP20 / 22 / 41 / 51
-- XY tables (SpectroScan, i1iO) when the `instlist` name matches `/spectro\s?scan|i1io/i`
+- XY tables (SpectroScan, i1iO) when the `instlist` name matches
+  `/spectro\s?scan|i1io/i`
 
 ## Docs
 
-Normative spec is [`docs/`](docs/README.md). Implementation order:
+| Where | Audience |
+|---|---|
+| [Wiki](https://git.i3omb.com/gronod/iccery-v2-mac/wiki) | End users — screens, workflow, troubleshooting |
+| [`docs/`](docs/README.md) | Functional spec (normative for implementers) |
+| [`AGENTS.md`](AGENTS.md), [`BUILD-PLAN.md`](BUILD-PLAN.md) | Agent / branch rules |
+
+Implementation order in `docs/`:
 
 | Doc | Topic |
 |---|---|
@@ -168,29 +249,40 @@ Normative spec is [`docs/`](docs/README.md). Implementation order:
 | [`docs/03-ipc-and-process-manager.md`](docs/03-ipc-and-process-manager.md) | Spawn / stdin / kill |
 | [`docs/04-argyll-binaries.md`](docs/04-argyll-binaries.md) | CLI argv |
 | [`docs/06-wizard-and-artefacts.md`](docs/06-wizard-and-artefacts.md) | Gating |
+| [`docs/23-assets.md`](docs/23-assets.md) | Icons, DMG chrome |
 | [`docs/24-issues-invariants.md`](docs/24-issues-invariants.md) | Bugs that must not return |
 | [`docs/26-v2-mac-ticket-plan.md`](docs/26-v2-mac-ticket-plan.md) | Gitea tickets |
 | [`docs/PREUAT.md`](docs/PREUAT.md) | Pre-UAT tester kit |
 
-Agent / branch rules: [`AGENTS.md`](AGENTS.md), [`BUILD-PLAN.md`](BUILD-PLAN.md).
-
 ## Git
 
 ```
-develop
+develop          # integration; PRs land here unless a milestone branch is announced
-  └── milestone/m10-studio   # M10 integration branch
+main             # protected release line (PR from develop)
-        └── feat/<issue>-<slug>    # one issue per branch
+feat/<issue>-<slug>
+fix/<issue>-<slug>
 ```
 
-Feature PRs target the current milestone branch, not `develop`. The milestone branch merges to `develop` when its issues are green. Completion PRs for issues #146–#149 target `milestone/m10-studio`; `milestone/m10-studio` merges into `develop` once all milestone gates pass. Do not open umbrella "bugfix" branches that mix tickets.
+Open feature/fix PRs against **`develop`**. A `milestone/m…` integration
+branch is used only while that milestone is assembling; `milestone/m10-studio`
+has been merged and deleted. Do not open umbrella “bugfix” branches that mix
+tickets.
+
+`main` is push-protected and requires status check
+`macOS CI / build-and-test (push)`. Protected **file** patterns on `main`
+block PR merges that touch matching paths — do not set that field to `*`.
 
 ## Licence
 
-GUI source: © 2026 Gordon Bolton — see [`LICENCE.md`](LICENCE.md). Viewing and personal evaluation only unless a separate grant says otherwise.
+GUI source: © 2026 Gordon Bolton — see [`LICENCE.md`](LICENCE.md). Viewing
+and personal evaluation only unless a separate grant says otherwise.
 
-ArgyllCMS binaries fetched into `Vendor/Argyll/` are **AGPLv3**. They stay subprocess-isolated (stdin / stdout / stderr only). Linking them, or spawning via `$PATH`, is a licence break.
+ArgyllCMS binaries fetched into `Vendor/Argyll/` are **AGPLv3**. They stay
+subprocess-isolated (stdin / stdout / stderr only). Linking them, or spawning
+via `$PATH`, is a licence break.
 
 ## Related
 
+- [User wiki](https://git.i3omb.com/gronod/iccery-v2-mac/wiki)
 - [gronod/argyllcms](https://git.i3omb.com/gronod/argyllcms) — Argyll 3.5.0 fork (`-u` JSON, `instlist`)
 - [gronod/ICCery](https://git.i3omb.com/gronod/ICCery) — v1 Tauri application (spec source, not this tree)

Sources/ICCery/AppEnvironment.swift

@@ -97,6 +97,12 @@ enum UITestHooks {
     static var projectSaveURL: URL? { url("ICCERY_TEST_PROJECT_SAVE") }
     /// Relocate-folder result when a project's `cwd` is missing (#149).
     static var projectRelocateURL: URL? { url("ICCERY_TEST_PROJECT_RELOCATE") }
+    /// Forces the gamut sheet into its no-Metal fallback even on a GPU
+    /// host (#147). Set per-test only — never in a default launch env,
+    /// or CI's future GPU run would skip SceneKit too.
+    static var skipSceneKit: Bool {
+        isEnabled && env["ICCERY_TEST_SKIP_SCENEKIT"] == "1"
+    }
 
     // MARK: - Print panel / CUPS stubs (issue 13/17)
 

Sources/ICCery/CalibrationView.swift

@@ -7,102 +7,135 @@ struct CalibrationView: View {
     @ObservedObject var wizard: WizardViewModel
 
     var body: some View {
-        VStack(alignment: .leading, spacing: 0) {
+        VStack(spacing: 0) {
-            Text("Calibrate Printer")
+            ScrollView {
-                .font(.title2.bold())
+                VStack(alignment: .leading, spacing: 16) {
-                .padding(.horizontal, 16)
+                    Text("Calibrate Printer")
-                .padding(.top, 16)
+                        .font(.title2.bold())
-
+                        .foregroundStyle(Theme.text)
-            Form {
+                    wedgeSection
-                Section("Wedge Settings") {
+                    workflowSection
-                    Picker("Colour Space", selection: $model.colourSpace) {
+                    if !model.calibrationLog.isEmpty { logSection }
-                        Text("RGB").tag(ColourSpace.rgb)
-                        Text("CMYK").tag(ColourSpace.cmyk)
-                    }
-
-                    HStack {
-                        Text("Steps per channel")
-                        Spacer()
-                        TextField("", value: $model.steps, format: .number)
-                            .frame(width: 60)
-                            .accessibilityIdentifier("calSteps")
-                    }
-
-                    HStack {
-                        Text("White patches")
-                        Spacer()
-                        TextField("", value: $model.whitePatches, format: .number)
-                            .frame(width: 60)
-                    }
-
-                    if model.colourSpace == .cmyk {
-                        HStack {
-                            Text("Ink-limit exploration")
-                            Spacer()
-                            TextField("", text: $model.inkLimit)
-                                .frame(width: 60)
-                                .accessibilityIdentifier("calInkExplore")
-                        }
-                    }
-
-                    Toggle("Neutral emphasis", isOn: $model.includeNeutralEmphasis)
-                }
-
-                Section("Workflow") {
-                    HStack(spacing: 12) {
-                        Button("Generate Target") { model.generateTarget() }
-                            .accessibilityIdentifier("btnCalGenerate")
-                            .disabled(wizard.basename.isEmpty
-                                      || wizard.effectiveWorkingDirectory == nil
-                                      || model.isGenerating)
-
-                        Button("Create Layout & Print") { model.createLayout() }
-                            .accessibilityIdentifier("btnCalLayout")
-                            .disabled(wizard.basename.isEmpty
-                                      || wizard.effectiveWorkingDirectory == nil
-                                      || model.isGenerating)
-
-                        Button("Measure") { model.measureChart() }
-                            .accessibilityIdentifier("btnCalMeasure")
-                            .disabled(model.calibrationTi3URL == nil)
-
-                        Button("Compute Curves") { model.computeCurves() }
-                            .accessibilityIdentifier("btnCalCompute")
-                            .disabled(!model.canCompute)
-                    }
-
-                    if let url = model.computedCalURL {
-                        Toggle("Apply calibration to next profile", isOn: $model.applyToProfile)
-                            .onChange(of: model.applyToProfile) { _ in model.updateApplyToProfile() }
-                            .accessibilityIdentifier("calApplyToggle")
-
-                        Text("Loaded: \(url.lastPathComponent)")
-                            .font(.caption)
-                            .foregroundStyle(.secondary)
-                    }
-                }
-
-                if !model.calibrationLog.isEmpty {
-                    Section("Log") {
-                        ScrollView {
-                            VStack(alignment: .leading, spacing: 2) {
-                                ForEach(model.calibrationLog, id: \.self) { line in
-                                    Text(line)
-                                        .font(.system(.caption, design: .monospaced))
-                                }
-                            }
-                        }
-                        .frame(minHeight: 80, maxHeight: 120)
-                    }
                 }
+                .padding(20)
+                .frame(maxWidth: .infinity, alignment: .leading)
             }
+            .background(Theme.background)
+
+            Divider().overlay(Theme.border)
 
             HStack {
                 Spacer()
-                Button("Return to Profiling") { model.returnToProfiling() }
+                Button("Return to Profiling", role: .cancel) { model.returnToProfiling() }
+                    .keyboardShortcut(.cancelAction)
                     .accessibilityIdentifier("btnCalReturn")
             }
             .padding(16)
         }
+        .accessibilityElement(children: .contain)
+        .accessibilityIdentifier("stage-cal")
+    }
+
+    // MARK: - Wedge settings
+
+    private var wedgeSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            Text("Wedge Settings").font(.headline).foregroundStyle(Theme.text)
+            Picker("Colour Space", selection: $model.colourSpace) {
+                Text("RGB").tag(ColourSpace.rgb)
+                Text("CMYK").tag(ColourSpace.cmyk)
+            }
+            .pickerStyle(.segmented)
+            .frame(maxWidth: 220)
+
+            HStack(spacing: 12) {
+                Text("Steps per channel")
+                    .foregroundStyle(Theme.text)
+                    .frame(width: 140, alignment: .leading)
+                TextField("", value: $model.steps, format: .number)
+                    .textFieldStyle(.roundedBorder)
+                    .frame(width: 70)
+                    .accessibilityIdentifier("calSteps")
+            }
+
+            HStack(spacing: 12) {
+                Text("White patches")
+                    .foregroundStyle(Theme.text)
+                    .frame(width: 140, alignment: .leading)
+                TextField("", value: $model.whitePatches, format: .number)
+                    .textFieldStyle(.roundedBorder)
+                    .frame(width: 70)
+            }
+
+            if model.colourSpace == .cmyk {
+                HStack(spacing: 12) {
+                    Text("Ink-limit exploration")
+                        .foregroundStyle(Theme.text)
+                        .frame(width: 140, alignment: .leading)
+                    TextField("", text: $model.inkLimit)
+                        .textFieldStyle(.roundedBorder)
+                        .frame(width: 70)
+                        .accessibilityIdentifier("calInkExplore")
+                }
+            }
+
+            Toggle("Neutral emphasis", isOn: $model.includeNeutralEmphasis)
+                .toggleStyle(.checkbox)
+                .foregroundStyle(Theme.text)
+                .accessibilityIdentifier("calNeutralEmphasis")
+        }
+    }
+
+    // MARK: - Workflow
+
+    private var workflowSection: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            Text("Workflow").font(.headline).foregroundStyle(Theme.text)
+            HStack(spacing: 12) {
+                Button("Generate Target") { model.generateTarget() }
+                    .accessibilityIdentifier("btnCalGenerate")
+                    .disabled(wizard.basename.isEmpty
+                              || wizard.effectiveWorkingDirectory == nil
+                              || model.isGenerating)
+
+                Button("Create Layout & Print") { model.createLayout() }
+                    .accessibilityIdentifier("btnCalLayout")
+                    .disabled(wizard.basename.isEmpty
+                              || wizard.effectiveWorkingDirectory == nil
+                              || model.isGenerating)
+
+                Button("Measure") { model.measureChart() }
+                    .accessibilityIdentifier("btnCalMeasure")
+                    .disabled(model.calibrationTi3URL == nil)
+
+                Button("Compute Curves") { model.computeCurves() }
+                    .accessibilityIdentifier("btnCalCompute")
+                    .disabled(!model.canCompute)
+            }
+
+            if let url = model.computedCalURL {
+                Toggle("Apply calibration to next profile", isOn: $model.applyToProfile)
+                    .toggleStyle(.checkbox)
+                    .foregroundStyle(Theme.text)
+                    .onChange(of: model.applyToProfile) { _ in model.updateApplyToProfile() }
+                    .accessibilityIdentifier("calApplyToggle")
+
+                Text("Loaded: \(url.lastPathComponent)")
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+            }
+        }
+    }
+
+    // MARK: - Log
+
+    private var logSection: some View {
+        ProcessLogView(
+            lines: model.calibrationLog,
+            minHeight: 80,
+            maxHeight: 120,
+            containerId: "calLogContainer",
+            logId: "calLog"
+        )
     }
 }

Sources/ICCery/GamutView.swift

@@ -74,6 +74,7 @@ struct GamutView: View {
     @StateObject private var viewModel: GamutViewModel
     @State private var pause: () -> Void = {}
     @FocusState private var isFocused: Bool
+    @Environment(\.dismiss) private var dismiss
     @Binding var showingAllHelp: Bool
 
     init(
@@ -94,6 +95,8 @@ struct GamutView: View {
             Divider().overlay(Theme.border)
             statusLine
             inspectPanel
+            Divider().overlay(Theme.border)
+            footer
         }
         .frame(minWidth: 720, minHeight: 520)
         .background(Theme.background)
@@ -142,7 +145,7 @@ struct GamutView: View {
             Text(layer?.displayName ?? fallback)
         }
         .toggleStyle(.checkbox)
-        .disabled(layer == nil || viewModel.viewerUnavailable)
+        .disabled(layer == nil)
         .help(layer.map { $0.sourceURL.lastPathComponent } ?? "No profile .gam loaded")
         // macOS 12 puts the identifier on the Toggle's container, an
         // element that never reports isEnabled — combine so the a11y
@@ -322,6 +325,21 @@ struct GamutView: View {
         }
     }
 
+    // MARK: - Footer
+
+    /// Always-visible Close (#147) — the fallback banner keeps it
+    /// reachable and Escape works via `.cancelAction` without SceneKit.
+    private var footer: some View {
+        HStack {
+            Spacer()
+            Button("Close") { dismiss() }
+                .keyboardShortcut(.cancelAction)
+                .accessibilityIdentifier("btnCloseGamut")
+        }
+        .padding(.horizontal, 12)
+        .padding(.vertical, 8)
+    }
+
     // MARK: - TIFF sample sheet
 
     private var tiffPreviewSheet: some View {
@@ -381,7 +399,9 @@ private struct GamutSceneView: NSViewRepresentable {
         context.coordinator.installKeyMonitor()
         context.coordinator.installClickGesture()
 
-        // No GPU → the docs/18 fallback; never respawn the view in a loop.
+        // Safety net only — the primary no-Metal check is
+        // `GamutSceneAvailability.isAvailable`, evaluated before this
+        // view is mounted. Never respawn the view in a loop.
         if MTLCreateSystemDefaultDevice() == nil {
             DispatchQueue.main.async { onUnavailable() }
         }

Sources/ICCery/GamutViewModel.swift

@@ -1,8 +1,21 @@
 import Combine
 import Foundation
 import ICCeryCore
+import Metal
 import simd
 
+/// Whether the SceneKit gamut scene can render on this host (#147).
+///
+/// Checked **before** `GamutSceneView` is mounted — constructing an
+/// `SCNView` on a Metal-less machine can wedge the main thread, which
+/// also stalls app quit behind the open sheet.
+enum GamutSceneAvailability {
+    static var isAvailable: Bool {
+        if UITestHooks.skipSceneKit { return false }
+        return MTLCreateSystemDefaultDevice() != nil
+    }
+}
+
 /// View model for the native SceneKit gamut viewer (issues #28, #147).
 ///
 /// Loads the bundled `sRGB.gam` reference immediately, the workflow's own
@@ -73,6 +86,8 @@ final class GamutViewModel: ObservableObject {
     init(environment: AppEnvironment, profileGamURL: URL? = nil) {
         self.environment = environment
         self.profileGamURL = profileGamURL
+        // Never let the view mount an SCNView without Metal (#147).
+        viewerUnavailable = !GamutSceneAvailability.isAvailable
         loadTask = Task { await load() }
     }
 

Sources/ICCery/RootView.swift

@@ -39,6 +39,7 @@ struct RootView: View {
                 }
                 WizardStageContent(model: model, workflow: workflow)
             }
+            .frame(maxWidth: .infinity, maxHeight: .infinity)
         }
         .frame(minWidth: 1100, minHeight: 700)
         .background(Theme.background)

Sources/ICCery/SettingsView.swift

@@ -69,22 +69,24 @@ struct SettingsView: View {
                 }
 
                 Section("Verification") {
-                    HStack {
+                    TextField(
-                        Text("Good ΔE ≤")
+                        "Good ΔE ≤",
-                        TextField(
+                        value: $model.settings.deltaEGoodMax,
-                            "2.0",
+                        format: .number
-                            value: $model.settings.deltaEGoodMax,
+                    )
-                            format: .number
+                    .accessibilityIdentifier("settingsDeltaEGood")
-                        )
+
-                        .frame(width: 60)
+                    TextField(
-                        Text("Warning ΔE ≤")
+                        "Warning ΔE ≤",
-                        TextField(
+                        value: $model.settings.deltaEWarningMax,
-                            "5.0",
+                        format: .number
-                            value: $model.settings.deltaEWarningMax,
+                    )
-                            format: .number
+                    .accessibilityIdentifier("settingsDeltaEWarning")
-                        )
+
-                        .frame(width: 60)
+                    Text("Swatch and verify status use these as the green / amber cutoffs. Fail is anything above Warning.")
-                    }
+                        .font(.caption)
+                        .foregroundStyle(.secondary)
+
                     ForEach(model.validationErrors, id: \.self) { error in
                         Text(error)
                             .font(.caption)
@@ -93,16 +95,12 @@ struct SettingsView: View {
                 }
 
                 Section("Calibration") {
-                    HStack {
+                    TextField(
-                        Text("Stale after")
+                        "Stale after (days)",
-                        TextField(
+                        value: $model.settings.calibrationStaleDays,
-                            "30",
+                        format: .number
-                            value: $model.settings.calibrationStaleDays,
+                    )
-                            format: .number
+                    .accessibilityIdentifier("settingsCalStaleDays")
-                        )
-                        .frame(width: 60)
-                        Text("days")
-                    }
                 }
 
                 Section("Profile install") {
@@ -143,6 +141,7 @@ struct SettingsView: View {
                     }
                 }
             }
+            .padding(.leading, 45)
 
             Divider()
 

Tests/ICCeryCoreTests/GamutViewModelTests.swift

@@ -1,4 +1,5 @@
 import Foundation
+import Metal
 import XCTest
 @testable import ICCeryCore
 @testable import ICCery
@@ -36,6 +37,15 @@ final class GamutViewModelTests: XCTestCase {
         XCTAssertTrue(vm.status.contains("faces"), "status: \(vm.status)")
     }
 
+    /// #147 — `viewerUnavailable` is decided before any `SCNView` is
+    /// mounted: it must exactly mirror Metal presence on this host.
+    func testViewerUnavailableMirrorsMetalAvailability() async throws {
+        let vm = try makeViewModel()
+        XCTAssertEqual(
+            vm.viewerUnavailable,
+            MTLCreateSystemDefaultDevice() == nil)
+    }
+
     func testMissingCompareGamLeavesSRGBAndSetsNotice() async throws {
         let vm = try makeViewModel()
         await vm.awaitInitialLoad()

Tests/ICCeryUITests/Milestone10GamutCompareUITests.swift

@@ -1,4 +1,5 @@
 import Foundation
+import Metal
 import XCTest
 
 /// Milestone 10 — Issue #147 gamut compare chrome tests.
@@ -9,6 +10,11 @@ import XCTest
 @MainActor
 final class Milestone10GamutCompareUITests: XCTestCase {
 
+    /// Metal on the test host — the app under test runs on the same
+    /// machine, so this predicts whether the sheet mounts SceneKit.
+    /// GPU-less runners still get the banner/Close assertions (#147).
+    private var hasGPU: Bool { MTLCreateSystemDefaultDevice() != nil }
+
     private var app: XCUIApplication!
     private var testRoot: URL!
     private var binDir: URL!
@@ -46,6 +52,10 @@ final class Milestone10GamutCompareUITests: XCTestCase {
     }
 
     override func tearDown() async throws {
+        // Never leave the gamut sheet up for `terminate()` (#147).
+        if app != nil, element("btnCloseGamut").exists {
+            element("btnCloseGamut").click()
+        }
         app?.terminate()
         app = nil
         if let testRoot {
@@ -104,6 +114,25 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         _ = waitFor("gamutView")
     }
 
+    /// Inverse of `waitFor` — polls until the element leaves the tree.
+    private func waitForGone(_ id: String, timeout: TimeInterval = 10) {
+        let deadline = Date().addingTimeInterval(timeout)
+        while Date() < deadline {
+            if !element(id).exists { return }
+            RunLoop.current.run(until: Date().addingTimeInterval(0.1))
+        }
+        XCTAssertFalse(element(id).exists, "Expected element \(id) to disappear")
+    }
+
+    /// `btnCloseGamut` dismisses the sheet so `tearDown`'s `terminate()`
+    /// is not stuck behind a key sheet (#147). No-op when already closed.
+    private func closeGamutSheet() {
+        let close = element("btnCloseGamut")
+        guard close.waitForExistence(timeout: 5) else { return }
+        close.click()
+        waitForGone("gamutView")
+    }
+
     func testLayerTogglesExistWithSRGB() throws {
         openGamutSheet()
 
@@ -115,6 +144,11 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         let compare = waitFor("gamutLayer-compare")
         XCTAssertTrue(compare.exists)
         XCTAssertFalse(compare.isEnabled, "Compare toggle must be disabled before a load")
+
+        let status = waitFor("gamutStatusText")
+        let statusValue = status.value as? String ?? ""
+        XCTAssertTrue(statusValue.contains("sRGB"), "Status should list the sRGB layer, got: \(statusValue)")
+        closeGamutSheet()
     }
 
     func testAddCompareButtonExists() throws {
@@ -128,6 +162,7 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         let status = waitFor("gamutStatusText")
         let value = status.value as? String ?? ""
         XCTAssertTrue(value.contains("sRGB"), "Status should keep the sRGB clause, got: \(value)")
+        closeGamutSheet()
     }
 
     func testCompareGamLoadEnablesToggle() throws {
@@ -142,6 +177,7 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         // The pre-load placeholder also exists — wait for enabled.
         let compare = waitUntilEnabled("gamutLayer-compare")
         XCTAssertTrue(compare.isEnabled, "Compare toggle should enable after load")
+        XCTAssertEqual(compare.value as? Int, 1, "Compare layer should be on after load")
 
         let status = waitFor("gamutStatusText")
         let value = status.value as? String ?? ""
@@ -149,6 +185,7 @@ final class Milestone10GamutCompareUITests: XCTestCase {
 
         let remove = waitFor("btnGamutRemoveCompare")
         XCTAssertTrue(remove.isEnabled)
+        closeGamutSheet()
     }
 
     func testOpenProfileRunsIccgamutForCompare() throws {
@@ -164,6 +201,13 @@ final class Milestone10GamutCompareUITests: XCTestCase {
 
         let compare = waitUntilEnabled("gamutLayer-compare")
         XCTAssertTrue(compare.isEnabled, "Compare toggle should enable after iccgamut")
+        XCTAssertEqual(compare.value as? Int, 1, "Compare layer should be on after iccgamut")
+
+        // The compare slot's display name is the .gam stem ("myprinter").
+        let status = waitFor("gamutStatusText")
+        let statusValue = status.value as? String ?? ""
+        XCTAssertTrue(statusValue.contains("myprinter"), "Status should list the compare layer, got: \(statusValue)")
+        closeGamutSheet()
     }
 
     func testInspectPanelIdleStableHeight() throws {
@@ -173,6 +217,7 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         XCTAssertTrue(panel.exists)
         XCTAssertTrue(element("gamutInspectIdle").exists)
         XCTAssertTrue(element("gamutStatusText").exists)
+        closeGamutSheet()
     }
 
     func testManualLabInspectShowsContainment() throws {
@@ -192,11 +237,55 @@ final class Milestone10GamutCompareUITests: XCTestCase {
         XCTAssertTrue(value.contains("in"), "Lab(50,0,0) should be inside sRGB, got: \(value)")
         XCTAssertTrue(element("gamutInspectL").exists)
         XCTAssertTrue(element("gamutInspectSwatch").exists)
+        closeGamutSheet()
     }
 
     func testResetIdentifierUnchanged() throws {
         openGamutSheet()
         let reset = waitFor("btnResetGamutCamera")
         XCTAssertTrue(reset.isEnabled)
+        closeGamutSheet()
+    }
+
+    /// `btnCloseGamut` is always enabled — including on the fallback
+    /// banner — and dismisses the sheet (#147).
+    func testCloseButtonDismissesSheet() throws {
+        openGamutSheet()
+
+        let close = waitFor("btnCloseGamut")
+        XCTAssertTrue(close.isEnabled)
+        close.click()
+        waitForGone("gamutView")
+    }
+
+    /// The fallback banner exists exactly when the host lacks Metal —
+    /// no `SCNView` is mounted on a GPU-less runner, and none may be
+    /// reported unavailable on a GPU host.
+    func testFallbackBannerMatchesGPUAvailability() throws {
+        openGamutSheet()
+
+        if hasGPU {
+            XCTAssertFalse(
+                element("gamutViewerUnavailable").exists,
+                "GPU host must mount the SceneKit view, not the fallback")
+        } else {
+            _ = waitFor("gamutViewerUnavailable")
+        }
+        closeGamutSheet()
+    }
+
+    /// `ICCERY_TEST_SKIP_SCENEKIT=1` forces the fallback even on a GPU
+    /// host — banner plus a working Close, no `SCNView` mounted (#147).
+    /// The env is set for this test only; the default launch env must
+    /// not carry it, or CI's future GPU run would skip SceneKit too.
+    func testForcedSceneKitSkipShowsBannerAndClose() throws {
+        app.launchEnvironment["ICCERY_TEST_SKIP_SCENEKIT"] = "1"
+        openGamutSheet()
+
+        _ = waitFor("gamutViewerUnavailable")
+        let close = waitFor("btnCloseGamut")
+        XCTAssertTrue(close.isEnabled)
+        close.click()
+        waitForGone("gamutView")
     }
 }

Tests/ICCeryUITests/Milestone3UITests.swift

@@ -113,6 +113,59 @@ final class Milestone3UITests: XCTestCase {
         return recordedLpArgv()
     }
 
+    /// Drags `#galleryPage-0`'s TIFF upward so `identifier`'s button
+    /// moves up, clear of the Dock collision zone at the window's
+    /// bottom edge (#132).
+    ///
+    /// macOS overlay scrollbars are not in the AX tree — never use
+    /// `app.scrollBars` — and a synthesized scroll wheel is inert on
+    /// this LazyVGrid, so the scroll is a real drag on the gallery
+    /// cell's content. A stale/off-screen AX frame resolves to a screen
+    /// point that can be a Dock icon — a coordinate click there once
+    /// opened Calendar instead of Print. Callers must click only when
+    /// the returned element `isHittable`; never coordinate-click a
+    /// stale frame.
+    @discardableResult
+    private func scrollStage2UntilHittable(
+        _ identifier: String,
+        timeout: TimeInterval = 20
+    ) -> XCUIElement {
+        var button = app.buttons[identifier]
+        let cell = app.descendants(matching: .any)["galleryPage-0"].firstMatch
+        XCTAssertTrue(cell.waitForExistence(timeout: 10), "galleryPage-0")
+
+        let deadline = Date().addingTimeInterval(timeout)
+        while Date() < deadline {
+            let windowBottom = app.windows.firstMatch.frame.maxY
+            if button.exists, button.isHittable,
+               button.frame.maxY < windowBottom - 80 {
+                return button
+            }
+            // Grab the upper half of the cell (the TIFF, not the Print
+            // button / Dock) and drag toward the top of the window.
+            // Mouse moves UP ⇒ gallery content moves UP ⇒ Print leaves
+            // the Dock zone.
+            if cell.isHittable {
+                let start = cell.coordinate(withNormalizedOffset:
+                    CGVector(dx: 0.5, dy: 0.25))
+                let end = start.withOffset(CGVector(dx: 0, dy: -280))
+                start.press(forDuration: 0.15, thenDragTo: end)
+            } else {
+                // Cell not hit-testable: drag the stage-2 content
+                // directly — still content, still never scrollBars.
+                let scrollView = app.scrollViews["stage-2"]
+                scrollView.coordinate(withNormalizedOffset:
+                    CGVector(dx: 0.5, dy: 0.55))
+                    .press(forDuration: 0.15, thenDragTo:
+                        scrollView.coordinate(withNormalizedOffset:
+                            CGVector(dx: 0.5, dy: 0.15)))
+            }
+            RunLoop.current.run(until: Date().addingTimeInterval(0.4))
+            button = app.buttons[identifier]
+        }
+        return button
+    }
+
     // MARK: - Tests
 
     /// Panel appears after the manifest; refresh populates the printer
@@ -199,36 +252,16 @@ final class Milestone3UITests: XCTestCase {
         XCTAssertTrue(app.buttons["btnPrintAll"].isEnabled)
 
         // The gallery cell's Print button sits at the window's bottom
-        // edge where synthesized scroll-wheel events are inert on the
+        // edge; scroll until it is genuinely hittable (#132). Never
-        // LazyVGrid (#132). Drag the NSScrollView's vertical AXScrollBar
+        // coordinate-click a stale frame — that point can be the Dock.
-        // thumb instead — a real scroll that re-renders the cell onscreen.
+        let printPage = scrollStage2UntilHittable("btnPrintPage-0")
-        var printPage = app.buttons["btnPrintPage-0"]
+        guard printPage.isHittable else {
-        let scrollDeadline = Date().addingTimeInterval(15)
-        while !printPage.isHittable, Date() < scrollDeadline {
-            let scroller = app.scrollBars.allElementsBoundByIndex
-                .first { $0.frame.height > $0.frame.width }
-            if let scroller {
-                scroller.coordinate(withNormalizedOffset:
-                    CGVector(dx: 0.5, dy: 0.1))
-                    .press(forDuration: 0.1, thenDragTo:
-                        scroller.coordinate(withNormalizedOffset:
-                            CGVector(dx: 0.5, dy: 0.6)))
-            } else {
-                app.scrollViews["stage-2"].scroll(byDeltaX: 0, deltaY: -1)
-            }
-            RunLoop.current.run(until: Date().addingTimeInterval(0.5))
-            printPage = app.buttons["btnPrintPage-0"]
-        }
-        if printPage.isHittable {
-            printPage.click()
-        } else {
-            // LazyVGrid cells can report a stale a11y frame — click the
-            // point directly; the lp argv assert below still verifies.
             print("AXTREE-BEGIN frame=\(printPage.frame)\n" +
                   "\(app.debugDescription)\nAXTREE-END")
-            printPage.coordinate(withNormalizedOffset:
+            XCTFail("btnPrintPage-0 never became hittable; frame=\(printPage.frame)")
-                CGVector(dx: 0.5, dy: 0.5)).click()
+            return
         }
+        printPage.click()
         let argv = waitForLpLine()
         XCTAssertTrue(argv.contains("AP_ColorMatchingMode"), argv)
         XCTAssertTrue(argv.contains("page1.tif"), argv)

Tests/ICCeryUITests/Milestone6CalibrationUITests.swift

@@ -86,6 +86,60 @@ final class Milestone6CalibrationUITests: XCTestCase {
         }
     }
 
+    /// Stage 0 must not push the sidebar off-screen: the macOS `Form`
+    /// rows with expanding spacers once gave the stage an unbounded ideal
+    /// width, and window centering shifted the 270 pt sidebar into
+    /// negative X (issue #163). AX-tree existence checks cannot see that,
+    /// so assert real frame geometry.
+    func testCalibrationViewDoesNotOverflowWindow() throws {
+        let calButton = app.buttons["btnCalibratePrinter"]
+        XCTAssertTrue(calButton.waitForExistence(timeout: 10))
+        calButton.tap()
+
+        XCTAssertTrue(app.staticTexts["Calibrate Printer"].waitForExistence(timeout: 5))
+
+        let window = app.windows.firstMatch
+        XCTAssertTrue(window.exists)
+        XCTAssertGreaterThanOrEqual(calButton.frame.minX, 0)
+        XCTAssertLessThanOrEqual(calButton.frame.maxX, window.frame.maxX)
+        let ret = app.buttons["btnCalReturn"]
+        XCTAssertTrue(ret.waitForExistence(timeout: 5))
+        XCTAssertTrue(ret.isHittable)
+    }
+
+    /// "Return to Profiling" is the single Stage 0 exit and carries the
+    /// cancel-action shortcut, so Escape must dismiss the dashboard too
+    /// (issue #163). `typeKey` delivery is unreliable on the macOS 12 CI
+    /// runner (m10 phase-08), so the Escape check falls back to the
+    /// deterministic button tap.
+    func testCalibrationReturnButtonAndEscapeDismiss() throws {
+        let calButton = app.buttons["btnCalibratePrinter"]
+        XCTAssertTrue(calButton.waitForExistence(timeout: 10))
+        calButton.tap()
+        XCTAssertTrue(app.staticTexts["Calibrate Printer"].waitForExistence(timeout: 5))
+
+        let returnButton = app.buttons["btnCalReturn"]
+        XCTAssertTrue(returnButton.waitForExistence(timeout: 5))
+        XCTAssertTrue(returnButton.isHittable)
+        returnButton.tap()
+
+        let stage1 = app.descendants(matching: .any)["stage-1"]
+        XCTAssertTrue(stage1.waitForExistence(timeout: 5))
+
+        // Re-enter and try Escape; fall back to the button where the
+        // runtime does not deliver typeKey.
+        XCTAssertTrue(calButton.waitForExistence(timeout: 5))
+        calButton.tap()
+        XCTAssertTrue(app.staticTexts["Calibrate Printer"].waitForExistence(timeout: 5))
+
+        app.typeKey(XCUIKeyboardKey.escape, modifierFlags: [])
+        if !stage1.waitForExistence(timeout: 4) {
+            XCTAssertTrue(returnButton.waitForExistence(timeout: 5))
+            returnButton.tap()
+            XCTAssertTrue(stage1.waitForExistence(timeout: 5))
+        }
+    }
+
     /// A failing calibration targen surfaces the error through the
     /// wizard notice and restores the original basename (issue #80).
     func testCalibrationTargenFailureRestoresBasename() throws {

Tests/ICCeryUITests/Milestone6GamutUITests.swift

@@ -1,10 +1,15 @@
 import Foundation
+import Metal
 import XCTest
 
 /// Milestone 6 — Issue #28 native SceneKit gamut viewer acceptance tests.
 @MainActor
 final class Milestone6GamutUITests: XCTestCase {
 
+    /// Metal on the test host — the app under test runs on the same
+    /// machine, so this predicts whether the sheet mounts SceneKit.
+    private var hasGPU: Bool { MTLCreateSystemDefaultDevice() != nil }
+
     private var app: XCUIApplication!
     private var testRoot: URL!
     private var binDir: URL!
@@ -64,6 +69,10 @@ final class Milestone6GamutUITests: XCTestCase {
     }
 
     override func tearDown() async throws {
+        // Never leave the gamut sheet up for `terminate()` (#147).
+        if app != nil, element("btnCloseGamut").exists {
+            element("btnCloseGamut").click()
+        }
         app?.terminate()
         app = nil
         if let testRoot {
@@ -90,10 +99,29 @@ final class Milestone6GamutUITests: XCTestCase {
         return el
     }
 
+    /// Inverse of `waitFor` — polls until the element leaves the tree.
+    private func waitForGone(_ id: String, timeout: TimeInterval = 10) {
+        let deadline = Date().addingTimeInterval(timeout)
+        while Date() < deadline {
+            if !element(id).exists { return }
+            RunLoop.current.run(until: Date().addingTimeInterval(0.1))
+        }
+        XCTAssertFalse(element(id).exists, "Expected element \(id) to disappear")
+    }
+
+    /// `btnCloseGamut` dismisses the sheet so `tearDown`'s `terminate()`
+    /// is not stuck behind a key sheet (#147). No-op when already closed.
+    private func closeGamutSheet() {
+        let close = element("btnCloseGamut")
+        guard close.waitForExistence(timeout: 5) else { return }
+        close.click()
+        waitForGone("gamutView")
+    }
+
     /// Build and verify the mock profile, then open the native gamut viewer.
     /// The viewer should load both the reference sRGB mesh and the profile
     /// gamut copied from that reference.
-    func testViewGamutOpensSceneKitSheet() throws {
+    private func openGamutSheet() {
         app.launch()
         if !app.wait(for: .runningForeground, timeout: 10) {
             app.activate()
@@ -105,6 +133,12 @@ final class Milestone6GamutUITests: XCTestCase {
 
         waitFor("btnViewGamut").click()
 
+        _ = waitFor("gamutView")
+    }
+
+    func testViewGamutOpensSceneKitSheet() throws {
+        openGamutSheet()
+
         let gamutView = waitFor("gamutView")
         XCTAssertTrue(gamutView.exists)
 
@@ -112,9 +146,33 @@ final class Milestone6GamutUITests: XCTestCase {
         let value = status.value as? String ?? ""
         XCTAssertTrue(value.contains("faces"), "Gamut status should report mesh faces, got: \(value)")
 
+        // The fallback banner appears exactly when the host lacks Metal
+        // — no SCNView is constructed without a GPU (#147).
+        if hasGPU {
+            XCTAssertFalse(
+                element("gamutViewerUnavailable").exists,
+                "GPU host must mount the SceneKit view, not the fallback")
+        } else {
+            _ = waitFor("gamutViewerUnavailable")
+        }
+
         // The reset button demonstrates that the viewer is interactive.
         let reset = waitFor("btnResetGamutCamera")
         XCTAssertTrue(reset.isEnabled)
+
+        closeGamutSheet()
+    }
+
+    /// Clicking Reset drives the live `SCNView` — runs only on Metal
+    /// hosts, skipped on GPU-less runners so the same suite exercises
+    /// 3D once CI has a GPU (#147).
+    func testResetCameraInteractsWithScene() throws {
+        guard hasGPU else { throw XCTSkip("No Metal") }
+        openGamutSheet()
+
+        let reset = waitFor("btnResetGamutCamera")
         reset.click()
+
+        closeGamutSheet()
     }
 }

Tests/ICCeryUITests/SettingsUITests.swift

@@ -0,0 +1,192 @@
+import Foundation
+import XCTest
+
+/// Settings sheet UI tests (issue #165).
+///
+/// The Verification thresholds once shared one non-wrapping `HStack` and
+/// drew past the sheet's right clip on the macOS grouped `Form`. AX
+/// existence cannot see clipping (#163), so containment is asserted on
+/// real frame geometry against the sheet's bounds.
+///
+/// All three numeric fields also passed their default value as the
+/// `TextField` label; inside an `HStack` row that label renders inline —
+/// it is not a placeholder — producing "Stale after 30 [30] days". The
+/// fields are now direct `Form` children, so the descriptive label
+/// renders once in the label column and the box fills the control
+/// column; `testNumericFieldsCarryLabelsNotDuplicatedValues` pins it.
+@MainActor
+final class SettingsUITests: XCTestCase {
+
+    private var app: XCUIApplication!
+
+    override func setUp() async throws {
+        continueAfterFailure = false
+        app = XCUIApplication()
+        app.launchEnvironment = ["ICCERY_UI_TESTING": "1"]
+        app.launch()
+        app.activate()
+    }
+
+    override func tearDown() async throws {
+        app?.terminate()
+        app = nil
+    }
+
+    /// Sheet content lives under `app.sheets`, outside the main window's
+    /// a11y tree (Milestone2 pattern).
+    private var sheet: XCUIElement {
+        app.sheets.firstMatch
+    }
+
+    private func openSettings() {
+        let gear = app.buttons["openSettingsBtn"]
+        XCTAssertTrue(gear.waitForExistence(timeout: 10))
+        gear.click()
+        XCTAssertTrue(sheet.waitForExistence(timeout: 10))
+    }
+
+    private func thresholdField(_ fieldID: String) -> XCUIElement {
+        let field = sheet.textFields[fieldID]
+        XCTAssertTrue(field.waitForExistence(timeout: 10), "missing \(fieldID)")
+        return field
+    }
+
+    private func replaceFieldValue(_ field: XCUIElement, with text: String) {
+        field.click()
+        app.typeKey("a", modifierFlags: .command)
+        field.typeText(text)
+    }
+
+    private func waitForSheetDismiss(timeout: TimeInterval = 10) {
+        let deadline = Date().addingTimeInterval(timeout)
+        while Date() < deadline {
+            if !sheet.exists { return }
+            RunLoop.current.run(until: Date().addingTimeInterval(0.1))
+        }
+        XCTAssertFalse(sheet.exists, "Expected sheet to disappear")
+    }
+
+    /// Both ΔE rows must render fully inside the 560×620 sheet: the
+    /// label-column `StaticText`s and the control-column fields all sit
+    /// within the sheet bounds, the two fields share the Form's control
+    /// column margin, and the Warning row sits below the Good row so the
+    /// two cannot overlap on one clipped line.
+    ///
+    /// The numeric fields are direct `Form` children, so macOS lifts
+    /// each `TextField` label into the right-aligned label column and
+    /// the editable box fills the control column — the same layout the
+    /// Pickers use. The control column ends only ~3.5 pt inside the
+    /// sheet (PopUpButtons reach it too), so the right-edge assertion is
+    /// "inside the sheet", not the older 12 pt compact-field inset.
+    func testVerificationRowsStayInsideSheet() throws {
+        openSettings()
+
+        let goodField = thresholdField("settingsDeltaEGood")
+        let warningField = thresholdField("settingsDeltaEWarning")
+
+        // Labels render as sibling staticTexts in the label column.
+        let goodLabel = sheet.staticTexts["Good ΔE ≤"]
+        let warningLabel = sheet.staticTexts["Warning ΔE ≤"]
+        XCTAssertTrue(goodLabel.waitForExistence(timeout: 5))
+        XCTAssertTrue(warningLabel.waitForExistence(timeout: 5))
+
+        // Left boundary: labels must be inside the sheet with >=12 pt inset
+        XCTAssertTrue(goodLabel.frame.minX >= sheet.frame.minX + 12.0)
+        XCTAssertTrue(warningLabel.frame.minX >= sheet.frame.minX + 12.0)
+
+        // Right boundary: fields must not draw past the sheet's clip
+        XCTAssertTrue(
+            goodField.frame.maxX <= sheet.frame.maxX,
+            "Good ΔE field clips the sheet's right edge")
+        XCTAssertTrue(
+            warningField.frame.maxX <= sheet.frame.maxX,
+            "Warning ΔE field clips the sheet's right edge")
+
+        // Vertical separation
+        XCTAssertTrue(
+            warningField.frame.minY > goodField.frame.minY,
+            "thresholds must be two separate rows")
+
+        // Both threshold fields align at the same control column margin
+        XCTAssertTrue(
+            abs(goodField.frame.minX - warningField.frame.minX) <= 1.0,
+            "Good and Warning ΔE fields should align at the same column margin")
+
+        // Other labels must not overflow the left boundary
+        let defaultInstLabel = sheet.staticTexts["Default instrument"]
+        XCTAssertTrue(defaultInstLabel.waitForExistence(timeout: 5))
+        XCTAssertTrue(
+            defaultInstLabel.frame.minX >= sheet.frame.minX + 12.0,
+            "Default instrument label must not overflow left edge")
+
+        let bundledSidecarsLabel = sheet.staticTexts["Bundled sidecars"]
+        XCTAssertTrue(bundledSidecarsLabel.waitForExistence(timeout: 5))
+        XCTAssertTrue(
+            bundledSidecarsLabel.frame.minX >= sheet.frame.minX + 12.0,
+            "Bundled sidecars label must not overflow left edge")
+
+        sheet.buttons["Cancel"].click()
+        waitForSheetDismiss(timeout: 5)
+    }
+
+    /// `warning <= good` fails `AppSettings.validate()` and keeps the
+    /// sheet open with the contract error text; restoring valid values
+    /// lets Save dismiss (issue #165 acceptance, strings are the #5
+    /// contract).
+    func testDeltaEValidationBlocksSaveThenValidSaveDismisses() throws {
+        openSettings()
+
+        replaceFieldValue(thresholdField("settingsDeltaEWarning"), with: "1")
+        sheet.buttons["Save"].click()
+
+        let error = sheet.staticTexts[
+            "Good ΔE threshold must be strictly less than the warning threshold."
+        ]
+        XCTAssertTrue(error.waitForExistence(timeout: 10))
+        XCTAssertTrue(sheet.exists, "invalid ΔE must not dismiss the sheet")
+
+        replaceFieldValue(thresholdField("settingsDeltaEWarning"), with: "5")
+        sheet.buttons["Save"].click()
+        waitForSheetDismiss(timeout: 10)
+    }
+
+    /// macOS renders a `TextField`'s first argument as a label, not a
+    /// placeholder — inside the old `HStack` rows it drew inline, so the
+    /// sheet read "Stale after 30 [30] days" / "Good ΔE ≤ 2.0 [2.0]".
+    /// As direct `Form` children each label now renders exactly once, in
+    /// the label column; no `staticText` may echo the field's value.
+    func testNumericFieldsCarryLabelsNotDuplicatedValues() throws {
+        openSettings()
+
+        // (identifier, label-column text, rendered default value, the
+        // literal that used to double-render as the field's label)
+        // `value:` shows the formatted number — 2.0 renders as "2".
+        let rows: [(id: String, label: String, value: String, dup: String)] = [
+            ("settingsDeltaEGood", "Good ΔE ≤", "2", "2.0"),
+            ("settingsDeltaEWarning", "Warning ΔE ≤", "5", "5.0"),
+            ("settingsCalStaleDays", "Stale after (days)", "30", "30"),
+        ]
+
+        for spec in rows {
+            let field = sheet.textFields[spec.id]
+            XCTAssertTrue(field.waitForExistence(timeout: 10), "missing \(spec.id)")
+            XCTAssertEqual(
+                field.value as? String, spec.value,
+                "\(spec.id) default value changed unexpectedly")
+            XCTAssertTrue(
+                sheet.staticTexts[spec.label].waitForExistence(timeout: 5),
+                "\(spec.id) must render \"\(spec.label)\" once in the label column")
+            for ghost in Set([spec.value, spec.dup]) {
+                XCTAssertFalse(
+                    sheet.staticTexts[ghost].exists,
+                    "\(spec.id) must not render \"\(ghost)\" as a second label")
+            }
+            XCTAssertTrue(
+                field.frame.maxX <= sheet.frame.maxX,
+                "\(spec.id) field clips the sheet's right edge")
+        }
+
+        sheet.buttons["Cancel"].click()
+        waitForSheetDismiss(timeout: 5)
+    }
+}

docs/23-assets.md

@@ -25,7 +25,7 @@ Cone-only mark for window/taskbar. Raster set:
 
 | File | Use |
 |------|-----|
-| `icons/dmg-background.png` (+ `@2x`, `.svg`) | macOS DMG window (ice cream / wordmark scene). Headless `dmgbuild` after #189 |
+| `Resources/dmg-background.png` (+ `@2x`; source `brand/dmg-background.svg`) | macOS DMG window. `scripts/package-release.sh` builds a HiDPI TIFF and passes it to `dmgbuild==1.6.7` from `build/.venv-dmgbuild` (created by `INSTALL_DMGBUILD=1 scripts/ensure-host-tools.sh`). Monterey Python 3.9 needs `PIP_IGNORE_REQUIRES_PYTHON=1` or pip will keep 1.6.5. Missing art is a hard fail (#95, #189). |
 | `icons/wix-banner.bmp`, `wix-dialog.bmp` | MSI |
 | `icons/nsis-header.bmp`, `nsis-sidebar.bmp` | NSIS |
 

project.yml

@@ -21,6 +21,8 @@ targets:
           - ICCery.entitlements
           - ICCery.Debug.entitlements
           - Argyll
+          - dmg-background.png
+          - dmg-background@2x.png
       - path: Resources/Argyll
         type: folder
     dependencies:

scripts/attach-release-asset.sh

@@ -30,6 +30,11 @@ if [ -z "$TAG" ] || [ "$TAG" = "${GITHUB_REF:-}" ]; then
     exit 1
 fi
 
+case "$TAG" in
+    *prerelease*) PRERELEASE=true ;;
+    *)            PRERELEASE=false ;;
+esac
+
 DMG="${1:-}"
 if [ -z "$DMG" ]; then
     DMG="$(ls -1 ICCery-*.dmg 2>/dev/null | head -n 1 || true)"
@@ -49,12 +54,12 @@ STATUS="$(curl -sS -o "$BODY" -w '%{http_code}' \
     "$API/repos/$REPO/releases/tags/$TAG" || true)"
 
 if [ "$STATUS" = "404" ]; then
-    echo "==> Creating release $TAG"
+    echo "==> Creating release $TAG (prerelease=$PRERELEASE)"
     STATUS="$(curl -sS -o "$BODY" -w '%{http_code}' \
         -H "Authorization: token $TOKEN" \
         -H "Content-Type: application/json" \
         -X POST "$API/repos/$REPO/releases" \
-        -d "{\"tag_name\":\"$TAG\",\"name\":\"$TAG\",\"prerelease\":true,\"target_commitish\":\"${GITHUB_SHA:-}\"}")"
+        -d "{\"tag_name\":\"$TAG\",\"name\":\"$TAG\",\"prerelease\":$PRERELEASE,\"target_commitish\":\"${GITHUB_SHA:-}\"}")"
 fi
 if [ "$STATUS" != "200" ] && [ "$STATUS" != "201" ]; then
     echo "error: could not load/create release $TAG (HTTP $STATUS)" >&2

scripts/dmgbuild-settings.py

@@ -1,10 +1,10 @@
 #!/usr/bin/env python3
 # scripts/dmgbuild-settings.py
 #
-# dmgbuild settings for ICCery. Set DMG_APP, DMG_FILENAME and DMG_VOLUME_NAME
+# dmgbuild settings for ICCery. scripts/package-release.sh exports
-# in the environment, or accept the defaults. Background art can be supplied
+# DMG_APP, DMG_FILENAME, DMG_VOLUME_NAME, and DMG_BACKGROUND (a
-# later by placing a PNG at Resources/dmg-background.png and setting
+# HiDPI TIFF). A missing background is a hard error — a grey
-# DMG_BACKGROUND.
+# Finder window is not an acceptable release artefact (#95).
 
 import os
 import sys
@@ -23,15 +23,23 @@ if not app_path or not app_path.endswith('.app') or not os.path.isdir(app_path):
 
 files = [app_path]
 
-# Background art is optional. If the referenced PNG does not exist, fall back
+# Finder on Sonoma+ is picky about PNG-with-alpha window pictures and
-# to a plain window. See docs/23-assets.md for the DMG background spec.
+# about classic Alias Manager blobs. package-release.sh always passes
-background = os.environ.get('DMG_BACKGROUND', 'Resources/dmg-background.png')
+# a flattened HiDPI TIFF as DMG_BACKGROUND. dmgbuild 1.6.7 (bookmark
-if background and not os.path.exists(background):
+# .DS_Store) needs Python >= 3.10, which the Monterey runner does not
-    background = None
+# have; 1.6.5 + TIFF is what CI can ship (#95).
+background = os.environ.get('DMG_BACKGROUND', '')
+if not background or not os.path.isfile(background):
+    sys.stderr.write(
+        'error: DMG_BACKGROUND must point at an existing image '
+        '(got %r)\n' % background)
+    sys.exit(1)
 
 icon = None
 
 # Window size is enough for the app icon and the Applications alias.
+# Bitmap is slightly larger than this rect so title-bar chrome on
+# 14+ does not crop the wordmark.
 window_rect = ((100, 100), (660, 400))
 
 # Use icon view without extra chrome.

scripts/ensure-host-tools.sh

@@ -2,19 +2,79 @@
 # scripts/ensure-host-tools.sh
 #
 # Bootstrap host tools needed by CI on the macOS 12 runner:
-#   - xcodegen: pinned prebuilt release from GitHub (Homebrew's current
+#   - xcodegen: always. Pinned prebuilt release from GitHub (Homebrew's
-#     formula requires Xcode 15.3, which cannot be installed on macOS 12).
+#     current formula requires Xcode 15.3, which cannot be installed on
-#   - dmgbuild: via pip3 (used by scripts/package-release.sh).
+#     macOS 12).
+#   - dmgbuild: only when INSTALL_DMGBUILD=1 or --dmgbuild. Isolated in
+#     build/.venv-dmgbuild so the test job never pip-installs it.
 #
-# Safe to run repeatedly: existing tools are left alone.
+# dmgbuild 1.6.6+, ds_store 1.3.2+ and mac_alias 2.2.3 declare
+# Requires-Python >= 3.10. The wheels are py3-none-any and run on the
+# runner's 3.9; PIP_IGNORE_REQUIRES_PYTHON is required or pip will only
+# offer 1.6.5 and keep a cached venv on that version (#95).
+# pip itself is capped at <26.1: 26.1+ needs Python 3.10.
+#
+# Safe to run repeatedly: existing tools are left alone unless the
+# dmgbuild pin is not met.
 
 set -eu
 
+ROOT="$(CDPATH='' cd -- "$(dirname -- "$0")/.." && pwd)"
 XCODEGEN_VERSION="2.38.0"
 INSTALL_ROOT="${XCODEGEN_HOME:-$HOME/.local/xcodegen/$XCODEGEN_VERSION}"
+VENV="$ROOT/build/.venv-dmgbuild"
+DMGBUILD_PIN="1.6.7"
 
-echo "==> Ensuring dmgbuild"
+INSTALL_DMGBUILD="${INSTALL_DMGBUILD:-0}"
-python3 -c "import dmgbuild" 2>/dev/null || pip3 install dmgbuild
+for arg in "$@"; do
+    case "$arg" in
+        --dmgbuild) INSTALL_DMGBUILD=1 ;;
+    esac
+done
+
+if [ "$INSTALL_DMGBUILD" = "1" ]; then
+    echo "==> Ensuring dmgbuild==$DMGBUILD_PIN in $VENV"
+    mkdir -p "$ROOT/build"
+    # pip 26.1+ requires Python 3.10 (dataclass slots). A leftover
+    # `pip install --upgrade pip` on this 3.9 venv installed 26.2.1 and
+    # the next pip invocation crashed. Recreate if pip is already dead.
+    if [ -x "$VENV/bin/python" ] \
+        && ! "$VENV/bin/python" -m pip --version >/dev/null 2>&1; then
+        echo "==> venv pip is broken; recreating $VENV"
+        rm -rf "$VENV"
+    fi
+    if [ ! -x "$VENV/bin/python" ]; then
+        python3 -m venv "$VENV"
+    fi
+    # Without this, pip on Python 3.9 hides 1.6.6+ and leaves 1.6.5.
+    PIP_IGNORE_REQUIRES_PYTHON=1
+    export PIP_IGNORE_REQUIRES_PYTHON
+    "$VENV/bin/python" -m pip install --upgrade 'pip>=24.3,<26.1'
+    "$VENV/bin/python" -m pip install --upgrade --force-reinstall \
+        "dmgbuild==$DMGBUILD_PIN" \
+        'ds_store>=1.3.3' \
+        'mac_alias>=2.2.3'
+    "$VENV/bin/python" -c 'from importlib.metadata import version
+print("dmgbuild", version("dmgbuild"))
+print("ds_store", version("ds_store"))
+print("mac_alias", version("mac_alias"))
+parts=[]
+for p in version("dmgbuild").split("."):
+    try:
+        parts.append(int("".join(c for c in p if c.isdigit()) or "0"))
+    except ValueError:
+        parts.append(0)
+parts += [0, 0, 0]
+raise SystemExit(0 if tuple(parts[:3]) >= (1, 6, 7) else 1)
+'
+    if [ -n "${GITHUB_PATH:-}" ]; then
+        echo "$VENV/bin" >> "$GITHUB_PATH"
+    fi
+    PATH="$VENV/bin:$PATH"
+    export PATH
+else
+    echo "==> Skipping dmgbuild (set INSTALL_DMGBUILD=1 for the package job)"
+fi
 
 if command -v xcodegen >/dev/null 2>&1; then
     echo "==> xcodegen already on PATH: $(xcodegen --version)"

scripts/package-release.sh

@@ -103,19 +103,39 @@ EOF
     scripts/verify-sidecar-signatures.sh "$APP"
 fi
 
-echo "==> Installing / locating dmgbuild"
+echo "==> Locating dmgbuild"
+# The package CI job already ran INSTALL_DMGBUILD=1 ensure-host-tools.sh,
+# which created build/.venv-dmgbuild and prepended it to PATH. Local
+# runs bootstrap the same venv if dmgbuild is missing.
+VENV="$ROOT/build/.venv-dmgbuild"
 if ! command -v dmgbuild >/dev/null 2>&1; then
-    VENV="$ROOT/build/.venv-dmgbuild"
+    if [ ! -x "$VENV/bin/dmgbuild" ]; then
-    if [ ! -d "$VENV/bin" ]; then
+        INSTALL_DMGBUILD=1 "$ROOT/scripts/ensure-host-tools.sh" --dmgbuild
-        python3 -m venv "$VENV"
-        "$VENV/bin/pip" install --upgrade pip
-        "$VENV/bin/pip" install dmgbuild
     fi
     PATH="$VENV/bin:$PATH"
     export PATH
 fi
 if ! command -v dmgbuild >/dev/null 2>&1; then
-    echo "error: dmgbuild not available. Try 'python3 -m venv .venv && pip install dmgbuild'" >&2
+    echo "error: dmgbuild not on PATH; run INSTALL_DMGBUILD=1 scripts/ensure-host-tools.sh" >&2
+    exit 1
+fi
+echo "dmgbuild $(command -v dmgbuild)"
+if [ -x "$VENV/bin/python" ]; then
+    "$VENV/bin/python" -c 'from importlib.metadata import version; print("dmgbuild", version("dmgbuild"))'
+fi
+
+PNG1X="$ROOT/Resources/dmg-background.png"
+PNG2X="$ROOT/Resources/dmg-background@2x.png"
+if [ ! -f "$PNG1X" ] || [ ! -f "$PNG2X" ]; then
+    echo "error: missing $PNG1X or $PNG2X" >&2
+    exit 1
+fi
+mkdir -p "$ROOT/build"
+DMG_BACKGROUND="$ROOT/build/dmg-background.tiff"
+echo "==> Building HiDPI DMG background TIFF"
+tiffutil -cathidpicheck "$PNG1X" "$PNG2X" -out "$DMG_BACKGROUND"
+if [ ! -f "$DMG_BACKGROUND" ]; then
+    echo "error: tiffutil did not write $DMG_BACKGROUND" >&2
     exit 1
 fi
 
@@ -128,6 +148,7 @@ VOLUME_NAME="ICCery ${VERSION}"
 DMG_APP="$APP" \
 DMG_FILENAME="$DMG" \
 DMG_VOLUME_NAME="$VOLUME_NAME" \
+DMG_BACKGROUND="$DMG_BACKGROUND" \
 dmgbuild -s scripts/dmgbuild-settings.py "$VOLUME_NAME" "$DMG"
 
 echo "DMG: $PWD/$DMG"