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OCaml project generator









  • Fixed the inheritance overwrites for multi-level inheritance



  • Added punctuation to prompts to improve the experience with monochrome terminals

  • Renamed Github to GitHub in prompts and documentation

  • Fixed extra leading spaces before the template name



  • Split the opam plugin in an opam-spin package.



  • Added an hello command to generate a tutorial project

  • Added a parse_binaries stanza that can be true to force Spin to parse binary files

  • Added a raw_files stanza that takes a list of file or glob expressions to instruct Spin to copy files instead of parsing them

  • Added a new c-bindings template for C bindings using ctypes

  • Added a new js template for javascript applications with js_of_ocaml


  • Removed the gen subcommand. The generators will come back with a much better workflow

  • Dropped support for Esy and Reason. The templates are now using the recommended OCaml setup only. The previous templates are hosted at https://github.com/ocaml-templates/

  • Changed the templates to use the ISC license

  • Increase version of ocamlformat to 0.18.0 in templates

  • Do not install merlin when installing dev dependencies in templates

  • Drop support for BuckleScript in PPX

  • Drop support for publishing on NPM for CLI and PPX templates

  • Update CI scripts to ocaml/setup-ocaml@v2

  • Remove python dependency to serve documentation in Makefile

  • Inline release script in Makefile

  • Remove global -open StdLabels in templates

  • The spa template has been removed from the official templates and now lives at https://github.com/ocaml-templates/spin-incr-dom

  • Spin does not parse binary files by default anymore, they are simply copied to the destination folder

  • Use test stanza for unit tests now that Alcotest prints colors by default

  • Remove unused flags defined in the root's dune file


  • The project generation will now fail before the configurations prompt if the output directory is not empty

  • By default, Spin now creates a local switch for the generated projects. This can be changed with spin config, or by setting the env variable SPIN_CREATE_SWITCH=false

  • Fix an CLI incompatibility between opam.2.0.X and opam.2.1.X that made Spin unusable with the former.



  • Added a new spa template to generate Single-Page-Application with Js_of_ocaml

  • Dune's --root argument in templates' Makefiles to better compose generated projects

  • The templates CI/CD is now caching Opam dependencies to improve build time

  • The templates are now installing locked dependencies by default during CI/CD

  • The Makefile of the templates include a small inlined python script to open the documentation with the default browser with the command servedoc


  • Removed the bs-react template from the official templates. The template now lives in tmattio/spin-rescript.

  • Removed dependency on Reason and use the generated project's Reason to convert .ml files to .re.


  • Fixed NPM release by vendoring a Chamomille-free version of Inquire

  • Remove wrong release flags from all templates

0.6.0 - 2020-05-17

This release is a complete rewrite of Spin.

Since the beginning of the project, a lot of learnings have been made and this new version incorporates these learning to build a solid foundation for the future of Spin.


  • New template DSL

  • Template inheritance with the (inherit ...) stanza

  • Documentation of the CLI and template DSL.

  • The CLI now provides a verbose flag to increase the verbosity

  • The git templates are now cached


  • Calling spin without a subcommand now displays a simpler usage documentation. The man page is available with spin --help

  • Better man page documentation

  • Better error messages

  • Improvements of the configuration prompts using Inquire

  • Update native templates to follow best practices (e.g. name of libraries)

  • The official templates are now embedded. No need to download a git repository, and the project generation works offline.


  • Bucklescript templates now fallback to using npm when yarn is absent

0.5.1 - 2020-03-17


  • Add versionning for the official templates to ensure updates on the templates don't break old version of Spin.

  • Sort spin ls result by name.


  • Rename react to bs-react. All the upcoming Bucklescript templates will be prefixed by bs-.

  • Add a lib template that is releasable on Opam.

  • Make the cli and ppx templates releasable on Opam.

  • Add support for Alcotest as an alternative to Rely in the native templates.

  • Add support for Opam as an alternative to Esy in the native templates.

  • Stop using Pesy and the dune files manually in each sub-directories.

  • Move the test_runner to a subdirectory support in test.

  • Extract the Contributing section of the README to a CONTRIBUTING.md file.

  • Add a CHANGES.md file that complies with dune-release requirements.

  • Use dune-release in the release scripts.

  • Remove homebrew Formula from the cli template that was a bad practice and didn’t allow users to update the generated projects.

  • Enable Windows in CI/CD of generated projects

0.5.0 - 2020-03-07


  • Before generating a template, Spin will check if the user has all the dependencies installed and exit gracefully if not. (by @citizen428)

  • Add a condition field in the postinstall stanza for the templates.


  • Print a warning when the update of the official templates failed, but continue the execution.

  • Do not update the official templates when running new with a local path or a git repository.

  • Remove some runtime dependencies to reduce Spin's binary size.


  • Trying to generate a file that already exists now raises an error instead of overwritting the file.

  • Fix to output a proper message when no generator exist for the current project.

  • Exit gracefully when failing to download a git repository or the initial templates for the first time. (by @citizen428)

0.4.8 - 2020-01-14


  • Support user configuration file that stores general configuration such as the user's name, GitHub author_name, etc.

  • Provide a config subcommand that can be used to change the user configuration.

  • The generators can now print a message when the generation succeeds with the message stanza.

0.4.7 - 2020-01-13


  • post_install stanza to run commands after installing a template now supports the working_dir stanza.
    The command will be executed in the given working directory.


  • Removed unused starting_command stanza.

  • Removed unused tutorial stanza.


  • Failure to parse a template file now prints an error with the file that cannot be parsed.

0.4.6 - 2020-01-11


  • Redirect stderr to dev null when calling git commands.


  • Fix a wrong exit code when calling a generator that does not exist.

  • Rename Homebrew formula to prevent duplication with existing spin formula.

  • Fix installation from NPM using yarn

~~0.4.5 - 2020-01-11~~

This release has been unpublished.

~~0.4.4 - 2020-01-11~~

This release has been unpublished.

~~0.4.3 - 2020-01-11~~

This release has been unpublished.

0.4.2 - 2020-01-06


  • Fix release artifacts on linux that was using darwin binaries.

0.4.1 - 2020-01-04


  • Use master branch of spin-templates.

  • The template argument in spin new is not required. To use the minimal template, you can run spin new native.


  • Use HTTPS instead of SSH to clone spin-templates.

  • Remove duplicated git clone logs.

0.4.0 - 2020-01-02


  • Create new projects from official templates with spin new TEMPLATE.

  • Create new projects from git repositories with spin new TEMPLATE.

  • Create new minimal projects with spin new when no argument is provided.

  • Generate new modules in existing Spin projects with spin gen [GENERATOR].

  • List existing official templates with spin ls.

  • Install with Homebrew.

  • Install with a bash script.