Building

The normal mix compile flow builds a local Open JTalk executable and, by default, installs a dictionary and voice under the application priv/ directory.

Requirements

The project supports Elixir 1.15 and later. Native compilation requires:

• gcc and g++, or the target's compatible C/C++ toolchain;
• make;
• curl;
• tar; and
• unzip.

On macOS, Xcode Command Line Tools provide the compiler and make.

First build and downloads

Hex releases do not contain the large upstream source and asset archives. A first compile normally requires outbound HTTPS access to SourceForge, Debian mirrors, and GNU Savannah.

Every downloaded input is pinned and checked against a SHA-256 digest before use. Later builds reuse verified archives and native outputs when their inputs have not changed.

Build flow

elixir_make invokes the repository Makefile, which coordinates the native build:

mix compile
  -> elixir_make
  -> Makefile
  -> scripts/prepare_vendor.sh
  -> scripts/build_openjtalk.sh
  -> priv/bin/open_jtalk

The build compiles MeCab 0.996, HTS Engine API 1.10, and Open JTalk 1.11. Extracted sources and Autotools-generated files stay under _build/.../obj/vendor/, separate from downloaded inputs in vendor/.

Native outputs are separated by target triplet. Changing the triplet discards incompatible intermediate state rather than reusing host or another target's objects.

Build options

Host builds default to dynamic linking with an executable-relative runtime library path. Builds with MIX_TARGET set request full static linking by default. Full static linking depends on the selected toolchain, including a static libstdc++, and is not supported for Darwin targets.

Runtime outputs

Compilation installs:

• priv/bin/open_jtalk;
• priv/lib/ when runtime libraries are needed;
• priv/dictionary/sys.dic when assets are bundled; and
• priv/voices/mei_normal.htsvoice when assets are bundled.

Removing _build resets generated native state. mix clean invokes the project's native clean target for the active build.

Tested combinations

CI covers:

• Elixir 1.15 / OTP 26 on Linux x86_64;
• Elixir 1.19 / OTP 28 on Linux x86_64 and aarch64;
• Elixir 1.19 / OTP 28 on macOS 14 arm64; and
• an aarch64 RPi 4 cross-build.

Other compatible Elixir, OTP, OS, and target combinations may work but are not part of the CI matrix.

Development checks

Run the same checks used by CI before submitting changes:

mix format --check-formatted
shellcheck -x scripts/*.sh
MIX_ENV=lint mix compile --warnings-as-errors
MIX_ENV=lint mix dialyzer --format short
MIX_ENV=lint mix credo --all --strict --format=oneline
mix test

Audio playback tests are excluded by default because they require a supported system player. Enable them with:

OPENJTALK_AUDIO_TESTS=1 mix test

Maintainers should also follow the repository-only release checklist when publishing a package.