diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c76b983..1b85e0f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,9 +17,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # macos-26 carries the Xcode 27 toolchain (macOS 27 SDK): the
-        # newest-SKU check alongside the macos-15 floor.
-        os: [macos-15, macos-26, ubuntu-24.04, windows-2025]
+        # macOS 26 is the minimum supported system, so macos-26 (which
+        # carries the Xcode 27 toolchain) is the only macOS leg.
+        os: [macos-26, ubuntu-24.04, windows-2025]
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v7
@@ -33,7 +33,7 @@ jobs:
           sudo apt-get install -y build-essential g++
           libxcb1-dev libxkbcommon-dev libxkbcommon-x11-dev
       - name: Format check
-        if: matrix.os == 'macos-15'
+        if: matrix.os == 'macos-26'
         run: cargo fmt --check
       - name: Clippy
         run: cargo clippy --all-targets -- -D warnings
diff --git a/README.md b/README.md
index 8cdff2f..649de92 100644
--- a/README.md
+++ b/README.md
@@ -45,7 +45,7 @@ To package locally: `scripts/package-macos.sh 0.1.0` produces
 
 | Platform | Status |
 | --- | --- |
-| macOS (Apple silicon / Intel) | built, tested, and manually verified — including on macOS 27 (Xcode 27 SDK) |
+| macOS 26+ (Apple silicon / Intel) | built, tested, and manually verified — including on macOS 27 (Xcode 27 SDK) |
 | Linux (X11 / Wayland) | compiles and unit-tested via CI; rendering uses Vulkan through blade-graphics, linking needs `libxcb`, `libxkbcommon`, `libxkbcommon-x11`, `libstdc++` |
 | Windows | compiles and unit-tested via CI (MSVC toolchain) |
 | FreeBSD | compiles via CI (GPUI gates its X11/Wayland backend to `linux` + `freebsd`); least-tested platform |
@@ -61,7 +61,7 @@ cross-platform; only the final Linux binary link needs native X11 libraries.
 
 - Stable Rust toolchain
 - `git` on your `PATH`
-- macOS: Xcode command line tools (`xcode-select --install`) for the Metal backend
+- macOS 26 or newer: Xcode command line tools (`xcode-select --install`) for the Metal backend
 - Linux: the X11/xkbcommon dev packages above plus a Vulkan-capable driver stack
 
 ## Usage
diff --git a/docs/BUILDING.md b/docs/BUILDING.md
index a4d8fb4..4091b84 100644
--- a/docs/BUILDING.md
+++ b/docs/BUILDING.md
@@ -19,10 +19,11 @@ does and why, per target.
 
 ### macOS
 
-Builds with Xcode 26 or 27 (macOS 26/27 SDK); the universal package is
-built on the newest CI runner image so releases pick up the latest
-SDK's platforms support while `LSMinimumSystemVersion` (13.0) keeps
-older systems working.
+Minimum supported system: **macOS 26**. Builds with Xcode 26 or 27
+(macOS 26/27 SDK); the universal package links with
+`MACOSX_DEPLOYMENT_TARGET=26.0` and carries
+`LSMinimumSystemVersion` 26.0, and CI builds/tests on the macos-26
+runner image.
 
 Requirements: stable Rust, Xcode command line tools
 (`xcode-select --install`).
diff --git a/scripts/package-macos.sh b/scripts/package-macos.sh
index a2edc6e..3e06a03 100755
--- a/scripts/package-macos.sh
+++ b/scripts/package-macos.sh
@@ -22,6 +22,10 @@ cd "$ROOT"
 
 echo "==> Building universal binary (aarch64 + x86_64 apple-darwin)"
 rustup target add aarch64-apple-darwin x86_64-apple-darwin
+# Minimum supported macOS: both slices link with a 26.0 floor, matching
+# LSMinimumSystemVersion below (Gatekeeper/LaunchServices enforce the
+# plist; the Mach-O min version is what older systems actually read).
+export MACOSX_DEPLOYMENT_TARGET=26.0
 cargo build --release --target aarch64-apple-darwin --target x86_64-apple-darwin
 
 rm -rf "$DIST"
@@ -52,7 +56,7 @@ cat > "$DIST/$APP_NAME.app/Contents/Info.plist" <<PLIST
     <key>CFBundleVersion</key><string>${VERSION}</string>
     <key>CFBundleShortVersionString</key><string>${VERSION}</string>
     <key>CFBundleInfoDictionaryVersion</key><string>6.0</string>
-    <key>LSMinimumSystemVersion</key><string>13.0</string>
+    <key>LSMinimumSystemVersion</key><string>26.0</string>
     <key>LSApplicationCategoryType</key><string>public.app-category.developer-tools</string>
     <key>NSHighResolutionCapable</key><true/>
     <key>NSSupportsAutomaticGraphicsSwitching</key><true/>