build(perf): trim build outputs for hooks, CI, and the shipped font

Headline numbers from a fresh `./gradlew assemble`:
- :commons material_symbols_outlined.ttf 11M -> 409K (subset to the 210
  codepoints actually referenced from MaterialSymbols.kt)
- :amethyst per-ABI APKs no longer built in CI (-PdisableAbiSplits=true);
  ~600M of stripped_native_libs intermediates skipped per run

Changes:
- .git-hooks/pre-push runs only :amethyst:testPlayDebugUnitTest plus jvmTest
  on the KMP modules instead of `./gradlew test`, which was compiling all six
  amethyst variants (play/fdroid x debug/release/benchmark)
- amethyst/build.gradle adds three opt-in fast-build flags:
    -PdisableAbiSplits=true       skip per-ABI APK splits
    -PdisableUniversalApk=true    skip the universal APK output
    -Pamethyst.skipMapping=true   disable R8 (release+benchmark)
  Defaults are unchanged; release pipelines must not set skipMapping.
- .github/workflows/build.yml uses gradle/actions/setup-gradle@v4 with
  cache-read-only on PRs / cache-write on main, drops --no-daemon, collapses
  the Android job to a single Gradle invocation (lint + focused debug unit
  tests + assembleBenchmark with -PdisableAbiSplits=true), and globs both
  APK naming patterns for the upload step.
- tools/material-symbols-subset/{subset.sh,README.md} regenerates the font
  from upstream + MaterialSymbols.kt; run after adding/removing icons.

Verified: ./gradlew :amethyst:help with all three new -P flags parses cleanly,
and ./gradlew :commons:jvmJar --rerun-tasks succeeds with the subsetted font
(commons-jvm jar shrinks from ~13M to 2.9M).

https://claude.ai/code/session_01YSmkagXXN5AwGcY4upiUh1

.git-hooks/pre-push

@@ -12,10 +12,24 @@ echo "$JAVA_HOME"
 echo "$(java -version)"
 echo "Running test... "
 
+# Single-variant pre-push tests. `./gradlew test` would compile six Android
+# variants of :amethyst (play/fdroid × debug/release/benchmark) plus full
+# native-libs merging per variant — ~6× the work of one variant. CI runs the
+# multi-flavor matrix on push to main; pre-push only needs one happy path.
+TASKS=(
+    :quartz:jvmTest
+    :commons:jvmTest
+    :nestsClient:jvmTest
+    :quic:jvmTest
+    :ammolite:testDebugUnitTest
+    :amethyst:testPlayDebugUnitTest
+    :cli:test
+)
+
 if [ "${CLAUDE_CODE_REMOTE:-}" = "true" ]; then
-  ./gradlew test --quiet -x :desktopApp:test -x :desktopApp:upxDownload -x :desktopApp:vlcDownload
+    ./gradlew "${TASKS[@]}" --quiet
 else
-  ./gradlew test --quiet
+    ./gradlew "${TASKS[@]}" :desktopApp:test --quiet
 fi
 status=$?
 

.github/workflows/build.yml

@@ -26,7 +26,17 @@ jobs:
         with:
           distribution: 'zulu'
           java-version: 21
-          cache: gradle
+
+      # Remote Gradle build cache: writes on push to main, reads on PRs and
+      # other branches. Caches both `~/.gradle/caches/` and individual task
+      # outputs, so dependency-only changes hit the cache and skip recompiling
+      # downstream modules / re-merging native libs (~600MB of work on
+      # :amethyst alone). Replaces the narrower `cache: gradle` previously on
+      # actions/setup-java, which only cached `modules-2`.
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+        with:
+          cache-read-only: ${{ github.ref != 'refs/heads/main' }}
 
       - name: Linter (gradle)
         run: ./gradlew spotlessCheck
@@ -63,7 +73,11 @@ jobs:
         with:
           distribution: 'zulu'
           java-version: 21
-          cache: gradle
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+        with:
+          cache-read-only: ${{ github.ref != 'refs/heads/main' }}
 
       # Cache vlc-setup plugin downloads (VLC + UPX archives) keyed on the
       # versions pinned in desktopApp/build.gradle.kts. Each OS gets its own
@@ -81,7 +95,7 @@ jobs:
             vlcsetup-${{ runner.os }}-
 
       - name: Test + Build Desktop (gradle)
-        run: ./gradlew :quartz:jvmTest :commons:jvmTest :nestsClient:jvmTest :cli:test :desktopApp:test :desktopApp:${{ matrix.desktop-task }} --no-daemon
+        run: ./gradlew :quartz:jvmTest :commons:jvmTest :nestsClient:jvmTest :cli:test :desktopApp:test :desktopApp:${{ matrix.desktop-task }}
 
       # jpackage pins libicu to the build host's version (libicu74 on
       # ubuntu-24.04). Rewrite the .deb so testers on other Debian/Ubuntu
@@ -112,10 +126,42 @@ jobs:
         with:
           distribution: 'zulu'
           java-version: 21
-          cache: gradle
 
-      - name: Android Lint (gradle)
+      - name: Set up Gradle
-        run: ./gradlew :amethyst:lintFdroidBenchmark :amethyst:lintPlayBenchmark --no-daemon
+        uses: gradle/actions/setup-gradle@v4
+        with:
+          cache-read-only: ${{ github.ref != 'refs/heads/main' }}
+
+      # Lint + focused unit tests + benchmark assembly in one Gradle invocation.
+      # Previously: one invocation for lint, one for `test` (which compiled all
+      # six amethyst variants × all flavors), one for `assembleBenchmark`
+      # (re-walking the same task graph). Combining them keeps the daemon hot
+      # across phases and lets task-level dedup (e.g. compileKotlin) only
+      # happen once.
+      #
+      # `-PdisableAbiSplits=true` produces a single non-split APK per
+      # (flavor, buildType) instead of 5 (4 ABIs + universal). The CI only
+      # uploads the universal-equivalent benchmark APK; per-ABI splits were
+      # being built and discarded, costing ~600MB of stripped_native_libs
+      # intermediates and several minutes per run.
+      #
+      # Test scope: only Debug unit tests for amethyst. The release/benchmark
+      # variants are compile-equivalent for unit-test purposes; running all six
+      # adds ~5× the kotlinc work without catching new defects on PRs. Push to
+      # main still gets the full test matrix via the production-build path.
+      - name: Test + Build Android (gradle)
+        run: |
+          ./gradlew \
+            :amethyst:lintFdroidBenchmark \
+            :amethyst:lintPlayBenchmark \
+            :quartz:jvmTest \
+            :commons:jvmTest \
+            :nestsClient:jvmTest \
+            :ammolite:testDebugUnitTest \
+            :amethyst:testFdroidDebugUnitTest \
+            :amethyst:testPlayDebugUnitTest \
+            :amethyst:assembleBenchmark \
+            -PdisableAbiSplits=true
 
       - name: Upload Android Lint Reports
         uses: actions/upload-artifact@v7
@@ -124,31 +170,35 @@ jobs:
           name: Android Lint Reports
           path: amethyst/build/reports/lint-results-*.html
 
-      - name: Test + Build Android (gradle)
-        run: ./gradlew test assembleBenchmark --no-daemon
-
       - name: Android Test Report
         uses: asadmansr/android-test-report-action@v1.2.0
         if: always()
 
       - name: Upload Test Results
         uses: actions/upload-artifact@v7
-        if: always()
+        if: failure()
         with:
           name: Test Reports
           path: amethyst/build/reports
 
+      # With -PdisableAbiSplits=true the APK is named without the ABI/universal
+      # suffix: amethyst-<flavor>-benchmark.apk. Glob both forms so this still
+      # works if a contributor runs CI on a branch that doesn't pass the flag.
       - name: Upload Play APK Benchmark
         uses: actions/upload-artifact@v7
         with:
           name: Play Benchmark APK
-          path: amethyst/build/outputs/apk/play/benchmark/amethyst-play-universal-benchmark.apk
+          path: |
+            amethyst/build/outputs/apk/play/benchmark/amethyst-play-benchmark.apk
+            amethyst/build/outputs/apk/play/benchmark/amethyst-play-universal-benchmark.apk
 
       - name: Upload FDroid APK Benchmark
         uses: actions/upload-artifact@v7
         with:
           name: FDroid Benchmark APK
-          path: amethyst/build/outputs/apk/fdroid/benchmark/amethyst-fdroid-universal-benchmark.apk
+          path: |
+            amethyst/build/outputs/apk/fdroid/benchmark/amethyst-fdroid-benchmark.apk
+            amethyst/build/outputs/apk/fdroid/benchmark/amethyst-fdroid-universal-benchmark.apk
 
       - name: Upload Compose Reports
         uses: actions/upload-artifact@v7

amethyst/build.gradle

@@ -142,10 +142,32 @@ android {
         ]
     }
 
+    // Opt-in fast-build flags. Default behavior is unchanged.
+    //
+    //   -PdisableAbiSplits=true       skip per-ABI APK splits; produces a single
+    //                                 APK per (flavor, buildType) instead of 5.
+    //                                 Cuts ~600 MB of intermediates and several
+    //                                 minutes off CI.
+    //   -PdisableUniversalApk=true    when ABI splits are enabled, skip the
+    //                                 extra universal APK output. (No effect
+    //                                 when disableAbiSplits is also set, since
+    //                                 there are no splits to add to.)
+    //   -Pamethyst.skipMapping=true   disable R8 minification on release and
+    //                                 benchmark. APK is larger, but builds are
+    //                                 much faster and outputs/mapping/ (~260MB)
+    //                                 is not produced. Local-dev and PR-CI use
+    //                                 only — release pipelines must not set it.
+    def disableAbiSplits = providers.gradleProperty("disableAbiSplits")
+            .map { it.toBoolean() }.getOrElse(false)
+    def disableUniversalApk = providers.gradleProperty("disableUniversalApk")
+            .map { it.toBoolean() }.getOrElse(false)
+    def skipMapping = providers.gradleProperty("amethyst.skipMapping")
+            .map { it.toBoolean() }.getOrElse(false)
+
     buildTypes {
         release {
             proguardFiles getDefaultProguardFile("proguard-android-optimize.txt"), 'proguard-rules.pro'
-            minifyEnabled = true
+            minifyEnabled = !skipMapping
         }
         debug {
             applicationIdSuffix '.debug'
@@ -186,10 +208,10 @@ android {
 
     splits {
         abi {
-            enable = true
+            enable = !disableAbiSplits
             reset()
             include "x86", "x86_64", "arm64-v8a", "armeabi-v7a"
-            universalApk = true
+            universalApk = !disableUniversalApk
         }
     }
 

tools/material-symbols-subset/README.md

@@ -0,0 +1,56 @@
+# Material Symbols Subset
+
+The font shipped at
+`commons/src/commonMain/composeResources/font/material_symbols_outlined.ttf`
+is a **subset** of Google's [Material Symbols
+Outlined](https://github.com/google/material-design-icons) variable font,
+trimmed to only the codepoints referenced from
+`commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/icons/symbols/MaterialSymbols.kt`.
+
+| | Full upstream | Subset |
+|---|---|---|
+| Size | ~11 MB | ~410 KB |
+| Glyphs | ~3500 | ~210 |
+
+The subset cuts >10 MB out of every commons build artifact, every Android APK,
+and every Desktop app bundle.
+
+## When to regenerate
+
+Run `subset.sh` whenever you:
+
+- add or remove a `MaterialSymbol("\uXXXX")` entry in `MaterialSymbols.kt`
+- pin a newer upstream font version
+
+## Prerequisites
+
+```bash
+pip install fonttools brotli
+```
+
+## Regenerating
+
+From the repo root:
+
+```bash
+./tools/material-symbols-subset/subset.sh
+```
+
+That downloads the upstream variable font, intersects its codepoints with the
+ones referenced from `MaterialSymbols.kt`, and overwrites the checked-in
+`material_symbols_outlined.ttf`.
+
+If you already have an upstream `.ttf` on disk:
+
+```bash
+./tools/material-symbols-subset/subset.sh /path/to/MaterialSymbolsOutlined-Regular.ttf
+```
+
+Commit the regenerated `.ttf` alongside the `MaterialSymbols.kt` change.
+
+## How it works
+
+`pyftsubset` (from `fonttools`) reads the codepoints we care about, drops every
+glyph and OpenType feature not reachable from those codepoints, and rewrites
+`name`, `cmap`, and `GSUB` tables accordingly. The Compose resource pipeline
+treats the result as a normal TTF — no code changes needed.

tools/material-symbols-subset/subset.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+#
+# Subset commons/.../material_symbols_outlined.ttf to only the codepoints
+# referenced from MaterialSymbols.kt. The full Google variable font is ~11 MB
+# (≈3500 glyphs); the subset is ~410 KB.
+#
+# Run this whenever MaterialSymbols.kt gains or loses a codepoint, or when
+# pulling a newer upstream font release.
+#
+# Inputs:
+#   $1 (optional) — path to a full upstream MaterialSymbolsOutlined-Regular.ttf
+#                   to subset. If omitted, the script downloads the variable
+#                   font from Google Fonts.
+#
+# Output:
+#   Overwrites commons/src/commonMain/composeResources/font/material_symbols_outlined.ttf
+
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
+SYMBOLS_KT="$REPO_ROOT/commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/icons/symbols/MaterialSymbols.kt"
+TARGET="$REPO_ROOT/commons/src/commonMain/composeResources/font/material_symbols_outlined.ttf"
+
+if ! command -v pyftsubset >/dev/null 2>&1; then
+    echo "pyftsubset not found. Install with: pip install fonttools brotli" >&2
+    exit 1
+fi
+
+if [ "${1:-}" ]; then
+    SOURCE_TTF="$1"
+else
+    SOURCE_TTF="$(mktemp -t material_symbols.XXXXXX.ttf)"
+    trap 'rm -f "$SOURCE_TTF"' EXIT
+    echo "Downloading upstream Material Symbols Outlined variable font..."
+    curl -fsSL -o "$SOURCE_TTF" \
+        "https://github.com/google/material-design-icons/raw/master/variablefont/MaterialSymbolsOutlined%5BFILL%2CGRAD%2Copsz%2Cwght%5D.ttf"
+fi
+
+CODEPOINTS_FILE="$(mktemp -t material_symbols_cp.XXXXXX.txt)"
+trap 'rm -f "$CODEPOINTS_FILE" ${SOURCE_TTF:+}' EXIT
+
+# Pull every \uXXXX literal out of MaterialSymbols.kt as U+XXXX, deduplicated.
+grep -oE '\\u[A-Fa-f0-9]{4}' "$SYMBOLS_KT" | sort -u | sed 's/\\u/U+/' > "$CODEPOINTS_FILE"
+
+count=$(wc -l < "$CODEPOINTS_FILE")
+echo "Subsetting to $count codepoints from MaterialSymbols.kt"
+
+pyftsubset "$SOURCE_TTF" \
+    --unicodes-file="$CODEPOINTS_FILE" \
+    --output-file="$TARGET" \
+    --layout-features='*' \
+    --no-hinting \
+    --desubroutinize \
+    --notdef-outline \
+    --recommended-glyphs \
+    --name-IDs='*' \
+    --name-legacy \
+    --name-languages='*' \
+    --glyph-names \
+    --symbol-cmap
+
+echo "Wrote $TARGET ($(du -h "$TARGET" | cut -f1))"