Installation

The quickest path is to download a release: every tagged release publishes a self-contained chartplotter for linux and windows (amd64 + arm64) on the releases page. Unpack the archive for your platform and run it — the web frontend and the S-101 catalogue are compiled in, so you supply only the ENC cells. macOS is not shipped as a prebuilt binary (the engine links Apple frameworks Zig can't cross-compile). To build it yourself on any platform — including macOS — follow Build from source below. go install …@latest does not work — the build statically links a native library and uses a local replace directive.

About the embedded IHO catalogues

The build embeds the IHO S-101 Portrayal and Feature Catalogues into the chart engine. The IHO publishes those catalogues in its own GitHub repositories with no declared license. The build fetches them via git submodules directly from the IHO's own repositories, and the resulting binaries — both what you build locally and what the project publishes on the releases page — embed that IHO material. The project distributes those binaries as an accepted position; see THIRD-PARTY-NOTICES.md.

Requirements

• Go 1.26 or newer.
• Zig 0.16 — builds the native libtile57 chart engine.
• git — clones the repos and the engine's IHO catalogue submodules.

Build from source

chartplotter is two repos that must sit side by side:

• chartplotter (Go) — the app: server, CLI, web frontend.
• tile57 (Zig) — the chart engine, built as the libtile57 static library. It has nested submodules of its own (the IHO catalogues).

The app's go.mod points at ../tile57/bindings/go, and its Makefile builds ../tile57/zig-out/lib/libtile57.a on demand — so the engine checkout (or a symlink to it) must be a sibling directory named tile57.

# 1. The engine, with its IHO catalogue submodules.
git clone https://github.com/beetlebugorg/tile57.git
cd tile57
git submodule update --init --recursive
cd ..

# 2. The app, as a sibling.
git clone https://github.com/beetlebugorg/chartplotter.git
cd chartplotter

# 3. Build: zig-builds libtile57, then a CGO go build.
make build

The build writes the binary to bin/chartplotter. Check that it works:

bin/chartplotter version

It prints the chartplotter version and the libtile57 engine version. The binary is self-contained — the web frontend and the S-101 catalogue are compiled in — so you can copy it to your PATH and run it anywhere on the same platform.

If you keep the engine checkout somewhere else, symlink it into place instead:

ln -s /path/to/your/tile57-checkout ../tile57

Make targets

The Makefile is the ground truth for the build — make build zig-builds libtile57 on demand and links it into the CGO binary, so there is no separate engine-build step. The targets you'll use most:

Target	What it does
make build	Build bin/chartplotter (zig-builds libtile57, then a CGO go build).
make test	go test ./....
make vet	go vet ./....
make fmt	gofmt -w ..
make serve	Build, then serve the web frontend on :8080 (HOST/PORT/ASSETS overridable).
make xbuild	Cross-compile release binaries with zig cc (linux + windows, amd64/arm64).

Run make fmt vet test before you commit. make xbuild deliberately skips macOS — Go's crypto/x509 links Apple frameworks Zig can't cross-compile, so a Mac binary must be built natively on a Mac. See CLAUDE.md for the full build contract.

Memory and disk

Baking tiles is the heavy step. Memory scales with the size and number of cells you bake at once, and baking many regions in parallel multiplies it. If you run on a small machine, such as a Raspberry Pi, bake one region at a time.

Once the tiles are built, the cost drops sharply. Serving charts streams pre-baked tiles from disk, so a running chartplotter serve uses only modest RAM — well within a small machine's budget. Plan your memory for the bake, not for everyday use.

Baked tiles live in your cache directory (~/.cache/chartplotter). Size depends on the area and detail, from a few megabytes for one harbor to gigabytes for a whole district.

Next steps

Bake your first chart in the Getting Started guide.