diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 00000000..5beb9a57
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,117 @@
+name: Release
+
+# Push a `vX.Y.Z` tag to cut a release: every supported target is built, the
+# archives are attached to a GitHub release, and the Homebrew tap is updated.
+# A tag carrying a suffix (`v0.3.0-rc1`) publishes as a prerelease and leaves
+# the tap alone — use one to prove the matrix before the real tag.
+on:
+  push:
+    tags: ["v*"]
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    name: ${{ matrix.target }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          # macOS builds run natively per arch. scripts/macho-align.sh (the
+          # ld64 repack of libtile57.a) invokes `ld -r` and libtool without
+          # -arch, so it can only repack for the host.
+          - { target: aarch64-macos, os: macos-latest }
+          - { target: x86_64-macos, os: macos-15-intel }
+          # -gnu, not -musl: build.zig retargets the CLI to static musl on a
+          # glibc host anyway, so these carry a portable `tile57` AND a
+          # libtile57.a that a glibc C host can link.
+          - { target: x86_64-linux-gnu, os: ubuntu-latest, deb: amd64 }
+          - { target: aarch64-linux-gnu, os: ubuntu-latest, deb: arm64 }
+          - { target: x86_64-windows-gnu, os: ubuntu-latest }
+          - { target: aarch64-windows-gnu, os: ubuntu-latest }
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          submodules: recursive
+
+      - name: Install Zig
+        uses: mlugg/setup-zig@v2
+        with:
+          version: 0.16.0
+
+      # The version is written in three places and the tag is a fourth. A
+      # mismatch ships a binary whose `tile57 version` contradicts its download.
+      - name: Check the tag against the version in the source
+        run: |
+          v="${GITHUB_REF_NAME#v}"; v="${v%%-*}"
+          grep -q "\.version = \"$v\"" build.zig.zon
+          grep -q "pub const version = \"$v\"" src/tile57.zig
+          grep -q "pub const VERSION = \"tile57 $v\"" tools/common.zig
+
+      - name: Build
+        run: zig build -Dtarget=${{ matrix.target }} -Doptimize=ReleaseFast
+
+      - name: Package
+        run: scripts/package-release.sh "${GITHUB_REF_NAME#v}" "${{ matrix.target }}" "${{ matrix.deb }}"
+
+      - uses: actions/upload-artifact@v7
+        with:
+          name: ${{ matrix.target }}
+          path: dist/*
+
+  release:
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/download-artifact@v8
+        with:
+          path: dist
+          merge-multiple: true
+
+      - name: Checksums
+        run: cd dist && shasum -a 256 tile57* > SHA256SUMS
+
+      - name: Publish
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: |
+          gh release create "$GITHUB_REF_NAME" --generate-notes --verify-tag \
+            ${{ contains(github.ref_name, '-') && '--prerelease' || '' }} \
+            dist/*
+
+  homebrew:
+    needs: release
+    if: ${{ !contains(github.ref_name, '-') }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+
+      - uses: actions/download-artifact@v8
+        with:
+          path: dist
+          merge-multiple: true
+
+      # A token with write access to the tap repo. Without it the release still
+      # stands; only the tap goes stale.
+      - name: Update the Homebrew tap
+        env:
+          TAP_TOKEN: ${{ secrets.HOMEBREW_TAP_TOKEN }}
+        run: |
+          if [ -z "$TAP_TOKEN" ]; then
+            echo "::warning::HOMEBREW_TAP_TOKEN is not set — skipping the tap update"
+            exit 0
+          fi
+          v="${GITHUB_REF_NAME#v}"
+          git clone --depth 1 \
+            "https://x-access-token:$TAP_TOKEN@github.com/beetlebugorg/homebrew-tap" tap
+          mkdir -p tap/Formula
+          scripts/brew-formula.sh "$v" dist > tap/Formula/tile57.rb
+          cd tap
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git add Formula/tile57.rb
+          git diff --cached --quiet || git commit -m "tile57 $v"
+          git push
diff --git a/.gitignore b/.gitignore
index d6eeb1d8..0f6bff8e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,6 +17,9 @@ cache.sqlite
 /.zig-cache/
 /zig-out/
 
+# Release archives staged by scripts/package-release.sh
+/dist/
+
 # Editor / OS
 *.swp
 .DS_Store
diff --git a/README.md b/README.md
index 42088d31..44908985 100644
--- a/README.md
+++ b/README.md
@@ -64,8 +64,7 @@ diagrams it carries.
 ## Start here
 
 ```sh
-git submodule update --init --recursive       # the vendored S-101 catalogue
-zig build                                     # writes zig-out/bin/tile57
+brew install beetlebugorg/tap/tile57          # or grab a binary from Releases
 
 tile57 bake ENC_ROOT -o out/                  # every chart -> its own archive
 tile57 png ENC_ROOT --view -76.48,38.974,15 --size 1600x1200 -o chart.png
@@ -75,8 +74,14 @@ tile57 bake harbour.KAP -o out/               # an RNC sheet -> the same archive
 tile57 png ENC_ROOT --over-image --view -76.48,38.974,15 -o over.png
 ```
 
-The first command bakes a catalogue. The second draws a chart straight to a PNG.
-The last one removes the chart's solid areas, so you can draw it over a photo.
+`bake` turns a catalogue into per-chart archives. `png` draws a chart straight to
+an image. `--over-image` removes the chart's solid areas, so you can draw it over
+a photo.
+
+Binaries for macOS, Linux and Windows are attached to every
+[release](https://github.com/beetlebugorg/tile57/releases), alongside a `.deb`
+and the static library. To build it yourself you need Zig 0.16 and the
+submodules — see [Installation](docs/docs/installation.md).
 
 ## What you can get
 
diff --git a/docs/docs/contributing.md b/docs/docs/contributing.md
index e2377370..3f3d8401 100644
--- a/docs/docs/contributing.md
+++ b/docs/docs/contributing.md
@@ -76,6 +76,32 @@ Direct pull requests are welcome. Please:
   [Installation](./installation.md)).
 - Expect review for correctness and safety, the same as AI-assisted changes.
 
+## Cutting a release
+
+The version lives in three files and has to agree with the tag — the release
+build checks all three and stops if they diverge:
+
+- `build.zig.zon` — `.version`
+- `src/tile57.zig` — `pub const version`
+- `tools/common.zig` — `pub const VERSION`
+
+Bump them, commit, then tag and push:
+
+```sh
+git tag v0.4.0 && git push origin v0.4.0
+```
+
+`.github/workflows/release.yml` builds macOS, Linux and Windows on x86-64 and
+arm64, attaches the archives, the `.deb`s and `SHA256SUMS` to a GitHub release,
+and updates the Homebrew tap. A tag with a suffix — `v0.4.0-rc1` — publishes as
+a prerelease and leaves the tap alone; use one to exercise the matrix before the
+real tag. `scripts/package-release.sh <version> <target>` produces the same
+archive locally after a `zig build`.
+
+The tap lives in [beetlebugorg/homebrew-tap](https://github.com/beetlebugorg/homebrew-tap)
+and its formula is generated, not hand-edited; the release workflow needs a
+`HOMEBREW_TAP_TOKEN` secret with write access to it.
+
 ## The process
 
 1. **Open** an issue or a requirement/prototype.
diff --git a/docs/docs/installation.md b/docs/docs/installation.md
index 02b8c6d8..245df7ec 100644
--- a/docs/docs/installation.md
+++ b/docs/docs/installation.md
@@ -6,63 +6,94 @@ sidebar_position: 2
 
 # Installation
 
-tile57 builds from source with **Zig 0.16** — no CMake, no system libraries
-beyond Zig itself. There are no pre-built binaries.
+Every [release](https://github.com/beetlebugorg/tile57/releases) ships pre-built
+binaries for macOS, Linux and Windows on x86-64 and arm64. Each archive carries
+the `tile57` CLI, the static library `libtile57.a`, and the C header
+`include/tile57.h`. The IHO S-101 Portrayal Catalogue is embedded in both, so
+nothing else has to be on disk at run time.
 
-## 1. Clone + fetch the submodules
+## Homebrew (macOS and Linux)
 
 ```sh
-git clone https://github.com/beetlebugorg/tile57.git
-cd tile57
-git submodule update --init --recursive
+brew install beetlebugorg/tap/tile57
 ```
 
-The vendored **IHO S-101 Portrayal Catalogue** comes in as a submodule (under
-`vendor/`). It is a **build-time** dependency: `zig build` embeds the
-catalogue (the Lua portrayal rules plus the symbols, line styles, area fills and
-colour profile) directly into the binary via `@embedFile`, so the resulting
-`tile57` needs no on-disk catalogue at runtime. Lua 5.4 is vendored under
-`vendor/lua` and compiled in, so no system Lua is needed either.
+## Debian and Ubuntu
+
+```sh
+curl -LO https://github.com/beetlebugorg/tile57/releases/latest/download/tile57_0.3.0_amd64.deb
+sudo apt install ./tile57_0.3.0_amd64.deb
+```
 
-## 2. Zig 0.16.0 (required)
+`arm64` is published alongside `amd64`. There is no apt repository — the `.deb`
+is a release asset, so upgrades mean downloading the next one.
 
-The engine, the `tile57` CLI, and the static library all need **Zig 0.16.0**.
-Install it from [ziglang.org/download](https://ziglang.org/download/) (pin
-0.16.0) and put it on your `PATH`.
+## Direct download
 
-## 3. Build + test
+Pick the archive for your platform from the
+[latest release](https://github.com/beetlebugorg/tile57/releases/latest) —
+`tile57-<version>-<arch>-<os>.tar.gz`, or `.zip` for Windows — and put `bin/tile57`
+on your `PATH`:
 
 ```sh
-zig build         # builds zig-out/bin/tile57 + libtile57.a
-zig build test    # runs the test suite
+tar xzf tile57-0.3.0-aarch64-macos.tar.gz
+sudo install -m755 tile57-0.3.0-aarch64-macos/bin/tile57 /usr/local/bin/
+tile57 version
 ```
 
-`zig build` produces:
+Every release includes a `SHA256SUMS` file. Verify before installing:
+
+```sh
+curl -LO https://github.com/beetlebugorg/tile57/releases/latest/download/SHA256SUMS
+shasum -a 256 -c SHA256SUMS --ignore-missing
+```
+
+macOS binaries are not notarized. Gatekeeper quarantines a downloaded archive, so
+clear it once — `xattr -d com.apple.quarantine ./tile57` — or install through
+Homebrew, which does it for you.
+
+## Build from source
+
+Building needs **Zig 0.16.0** and nothing else — no CMake, no system libraries.
+Install Zig from [ziglang.org/download](https://ziglang.org/download/) (pin
+0.16.0) and put it on your `PATH`.
+
+```sh
+git clone https://github.com/beetlebugorg/tile57.git
+cd tile57
+git submodule update --init --recursive   # the vendored S-101 catalogue
+zig build                                 # builds zig-out/bin/tile57 + libtile57.a
+zig build test                            # runs the test suite
+```
 
 | Target | What it is |
 |--------|-----------|
 | `tile57` (`zig-out/bin/tile57`) | the offline CLI: bake charts/ENC_ROOTs to PMTiles or a chart bundle, and emit portrayal assets. |
 | `libtile57.a` | the static library behind the [C ABI](./c-api.md) (`include/tile57.h`). |
 
-The engine is also a Zig package named `tile57` (v0.3.0); a Zig consumer
-depends on it and uses `@import("tile57")` — see the [Zig API](./zig-api.md).
+The **IHO S-101 Portrayal Catalogue** comes in as a git submodule under `vendor/`.
+It is a *build-time* dependency: `zig build` embeds the catalogue — the Lua
+portrayal rules plus the symbols, line styles, area fills and colour profile —
+directly into the binary via `@embedFile`. Lua 5.4 is vendored under `vendor/lua`
+and compiled in, so no system Lua is needed either.
+
+## As a Zig package
+
+The engine is a Zig package named `tile57` (v0.3.0). Fetch it by tag:
 
-:::note Consume it as a path dependency (for now)
-Depend on a local clone via a `.path` dependency in your `build.zig.zon`,
-with the clone's submodules initialised:
+```sh
+zig fetch --save "https://github.com/beetlebugorg/tile57/archive/refs/tags/v0.3.0.tar.gz"
+```
 
 ```zig
-.dependencies = .{
-    .tile57 = .{ .path = "../tile57" },
-},
+const tile57 = b.dependency("tile57", .{ .target = target, .optimize = optimize });
+exe.root_module.addImport("tile57", tile57.module("tile57"));
 ```
 
-**Known issue:** fetching by URL/hash (`zig fetch --save <url>`) does not work
-yet — `build.zig.zon`'s `.paths` currently ships only `build.zig`,
-`build.zig.zon`, and `src/`, so a fetched package is missing `vendor/` (the
-embedded catalogue + Lua), `include/`, `tools/`, and the LICENSE, and cannot
-build. Until that's fixed, use a path dependency.
-:::
+A fetched package carries its own copy of the portrayal catalogue (Zig's fetcher
+does not follow git submodules, so the catalogue arrives as a lazy package
+dependency instead) — no submodule init needed. See the
+[Zig API](./zig-api.md) for what the module exposes.
 
 ## Runtime knob
 
diff --git a/docs/docs/zig-api.md b/docs/docs/zig-api.md
index 387541b2..26fc047e 100644
--- a/docs/docs/zig-api.md
+++ b/docs/docs/zig-api.md
@@ -14,10 +14,9 @@ source charts bake once to per-chart archives, and every output is produced
 from baked archives. These pages are grouped the same way as the [C API](./c-api.md).
 
 :::note
-Add it as a **path dependency** on a local clone (submodules initialised) —
-`zig fetch` by URL/hash is currently broken because the package's declared
-`.paths` omit `vendor/` and `include/`. See
-[Installation](./installation.md).
+`zig fetch --save "https://github.com/beetlebugorg/tile57/archive/refs/tags/v0.3.0.tar.gz"`
+adds it. A fetched package carries the S-101 catalogue as a lazy dependency, so
+there are no submodules to initialise. See [Installation](./installation.md).
 :::
 
 ## Sections
diff --git a/scripts/brew-formula.sh b/scripts/brew-formula.sh
new file mode 100755
index 00000000..06aebde2
--- /dev/null
+++ b/scripts/brew-formula.sh
@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+# Print the Homebrew formula for a released version, reading each archive's
+# sha256 out of <dist-dir> (the tarballs that release.yml just published).
+# The tap job pipes this into Formula/tile57.rb.
+#
+# Usage: brew-formula.sh <version> <dist-dir>
+set -euo pipefail
+
+version="$1"
+dist="$2"
+base="https://github.com/beetlebugorg/tile57/releases/download/v$version"
+
+sha() { shasum -a 256 "$dist/tile57-$version-$1.tar.gz" | cut -d' ' -f1; }
+
+# Resolved before the heredoc: a command substitution that fails inside one is
+# not caught by `set -e`, and a missing archive would emit an empty sha256.
+mac_arm="$(sha aarch64-macos)"
+mac_intel="$(sha x86_64-macos)"
+linux_arm="$(sha aarch64-linux-gnu)"
+linux_intel="$(sha x86_64-linux-gnu)"
+
+cat <<EOF
+class Tile57 < Formula
+  desc "Nautical chart engine: IHO S-101 and S-57 charts to tiles, PNG, and PDF"
+  homepage "https://github.com/beetlebugorg/tile57"
+  version "$version"
+  license "MIT"
+
+  on_macos do
+    on_arm do
+      url "$base/tile57-$version-aarch64-macos.tar.gz"
+      sha256 "$mac_arm"
+    end
+    on_intel do
+      url "$base/tile57-$version-x86_64-macos.tar.gz"
+      sha256 "$mac_intel"
+    end
+  end
+
+  on_linux do
+    on_arm do
+      url "$base/tile57-$version-aarch64-linux-gnu.tar.gz"
+      sha256 "$linux_arm"
+    end
+    on_intel do
+      url "$base/tile57-$version-x86_64-linux-gnu.tar.gz"
+      sha256 "$linux_intel"
+    end
+  end
+
+  def install
+    bin.install "bin/tile57"
+    lib.install "lib/libtile57.a"
+    include.install "include/tile57.h"
+  end
+
+  test do
+    assert_match version.to_s, shell_output("#{bin}/tile57 version 2>&1")
+  end
+end
+EOF
diff --git a/scripts/package-release.sh b/scripts/package-release.sh
new file mode 100755
index 00000000..06275b30
--- /dev/null
+++ b/scripts/package-release.sh
@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+# Stage a built tree into the release archive for one target, and — when a
+# Debian architecture is given — the matching .deb. Run it after
+# `zig build -Dtarget=<target> -Doptimize=ReleaseFast`; everything lands in
+# dist/. Invoked per target by .github/workflows/release.yml.
+#
+# Usage: package-release.sh <version> <target> [deb-arch]
+set -euo pipefail
+
+version="$1"
+target="$2"
+deb_arch="${3:-}"
+
+root="$(cd "$(dirname "$0")/.." && pwd)"
+out="$root/dist"
+name="tile57-$version-$target"
+stage="$out/$name"
+
+exe=tile57
+case "$target" in *windows*) exe=tile57.exe ;; esac
+
+rm -rf "$stage"
+mkdir -p "$stage/bin" "$stage/lib" "$stage/include"
+cp "$root/zig-out/bin/$exe" "$stage/bin/"
+cp "$root"/zig-out/lib/* "$stage/lib/"
+cp "$root/include/tile57.h" "$stage/include/"
+cp "$root/LICENSE" "$root/THIRD_PARTY_LICENSES.md" "$root/README.md" "$stage/"
+
+cd "$out"
+case "$target" in
+  *windows*) rm -f "$name.zip" && zip -qr "$name.zip" "$name" ;;
+  *) tar czf "$name.tar.gz" "$name" ;;
+esac
+
+# The same payload under /usr, for `apt install ./tile57_*.deb`. There is no
+# apt repository — the .deb is a release asset.
+if [ -n "$deb_arch" ]; then
+  pkg="$out/deb"
+  rm -rf "$pkg"
+  mkdir -p "$pkg/DEBIAN" "$pkg/usr/bin" "$pkg/usr/lib" "$pkg/usr/include" \
+           "$pkg/usr/share/doc/tile57"
+  install -m755 "$stage/bin/tile57" "$pkg/usr/bin/"
+  install -m644 "$stage/lib/libtile57.a" "$pkg/usr/lib/"
+  install -m644 "$stage/include/tile57.h" "$pkg/usr/include/"
+  install -m644 "$root/LICENSE" "$pkg/usr/share/doc/tile57/copyright"
+  cat > "$pkg/DEBIAN/control" <<EOF
+Package: tile57
+Version: $version
+Architecture: $deb_arch
+Maintainer: Jeremy Collins <jeremy.collins@beetlebug.org>
+Section: science
+Priority: optional
+Homepage: https://github.com/beetlebugorg/tile57
+Description: Nautical chart engine for IHO S-101 and S-57 charts
+ tile57 reads IHO S-101 and S-57 electronic navigational charts and renders
+ them with the official IHO S-101 Portrayal Catalogue: vector tiles with a
+ matching MapLibre S-52 style, a draw-ready GPU scene, PNG, and PDF. It also
+ reads raster charts (MBTiles, BSB/KAP) and draws the official chart over
+ them. Ships the tile57 CLI plus libtile57.a and its C header.
+ .
+ Not for navigation.
+EOF
+  dpkg-deb --build --root-owner-group "$pkg" "$out/tile57_${version}_${deb_arch}.deb"
+  rm -rf "$pkg"
+fi
+
+rm -rf "$stage"
+ls -l "$out"