OCaml-safepass is a library enabling the safe storage of user passwords, for use in web applications
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OCaml-safepass is a library offering facilities for the safe storage of user passwords. By "safe" we mean that passwords are salted and hashed using the Bcrypt algorithm. Salting prevents rainbow-table based attacks, whereas hashing by a very time-consuming algorithm such as Bcrypt renders brute-force password cracking impractical.

OCaml-safepass's obvious usage domain are web applications, though it does not depend on any particular framework. Internally, OCaml-safepass binds to the C routines from Openwall's Crypt_blowfish. However, it would be incorrect to describe OCaml-safepass as an OCaml binding to Crypt_blowfish, because the API it exposes is higher-level and more compact than that offered by Crypt_blowfish. Moreover, OCaml-safepass's API takes advantage of OCaml's type-system to make usage mistakes nearly impossible.


OCaml-safepass has no external dependencies. Note that it bundles the Public Domain licensed crypt_blowfish.h and crypt_blowfish.c C modules from Openwall's Crypt_blowfish.

Building and installing

OCaml-safepass is available in OPAM, which is the recommended installation method. If you wish to compile it yourself manually, note that the build system uses Dune. You can use the customary make to build OCaml-safepass, and make doc to generate the API documentation.


OCaml-safepass is distributed under the terms of the GNU LGPL version 2.1 with the usual OCaml linking exception. See LICENSE file for full license text.