Latest stable version: 3.23.0
Release date: January 30, 2019


Logtalk runs on any operating-system with a standards compliant modern Prolog compiler. The interface between Logtalk and a specific backend Prolog compiler is accomplished using a small adapter file. The Logtalk distribution includes adapter files for all supported Prolog compilers:

Legacy Logtalk versions (2.x) provide support for some other Prolog compilers, which are no longer supported due to lack of compliance with official and de facto standards.

Be sure to install the Prolog systems that you want to use as backend compilers before installing Logtalk.


Logtalk is an open source programming language, distributed under the Apache License 2.0. The copyright notice and license applies to all files in this release (including sources, documentation, and examples) unless otherwise explicitly stated.

Git repo

The Logtalk git repo is currently hosted at GitHub. Follow these steps for running Logtalk development versions. See the release notes for the latest changes.

You may keep up to date on development changes by subscribing to the Logtalk commits RSS feed.


10c127c676e7b88142ddf29543daf7075572203bd2010e48f6ea913fe018ead5 (SHA-256)

Includes the HTML versions of the Handbook and the APIs documentation.


Be sure to read the,, and files on the Logtalk user directory for important information, including instructions on how to customize and run Logtalk. For Windows users, this information is also available from the Logtalk program group in the Start Menu.

The following installers are available for the latest version:


Based on the MacPorts portfile. Installs Logtalk on /opt/local/share/ with integration scripts for supported Prolog compilers on /opt/local/bin. Creates an /Applications/Logtalk folder with links to the installed files.
64c137ce3f1ce2d29adaf3e77c3f1a14ecf35d0939fe355f3ec9ef4629ce8c57 (SHA-256)

A MacPorts portfile is also available. Users may simply type the command sudo port install logtalk (or sudo port upgrade logtalk) in order to install (or upgrade) Logtalk. Homebrew users may simply type the command brew install logtalk (or brew upgrade logtalk) in order to install (or upgrade) Logtalk. But do check first that the MacPorts portfile and the Homebrew formula are up-to-date.


Installs Logtalk on /usr/local/share with integration scripts for supported Prolog compilers on /usr/local/bin. Package installation from the command-line is recommended.

978a125bf66cb7c8c5af16de7a2577d21fc4169958ef46c446df34bfbe4a5b79 (SHA-256)

Debian (e.g. Ubuntu)

Requires dpkg 1.15.0 or a later version. Installs Logtalk on /usr/share with integration scripts for supported Prolog compilers on /usr/bin. Package installation from the command-line is recommended.

0c80e85b90c7a366c785e392b4fe2a1dc8ce67b5cc1940e5f9a9d1878c1cbae9 (SHA-256)


Be sure to install a compatible Prolog compiler before running the Logtalk installer. Creates a Logtalk program group in the Start Menu with integration shortcuts for supported Prolog compilers and shortcuts for the accessing the Logtalk documentation. Can be used by both admin and non-admin users.

a15c9ac35391a3b16578f95317589532c4bd45304fcb2589fb74279e86265d6b (SHA-256)

SWI-Prolog pack

Logtalk is also available as a SWI-Prolog pack. The pack is handy for deployment but not ideal for development, however, as the all the files in the distribution are buried in a relatively deep sub-directory. The pack can be easily installed typing the query pack_install(logtalk) at the top-level. Also available as a manual download.

05438fe64ebb535fd7ee100cc23d4310bd60b5ee9df4c156a48fc86d068ef4b3 (SHA-256)

Arch Linux package

Logtalk is also available as an Arch Linux package contributed by Ebrahim Azarisooreh.


HTML, ePub, and PDF versions of the Handbook (includes a tutorial, the User Manual, the Reference Manual, and the FAQ). Note that the HTML version is included in the source and binary packages.

3ba56dd6b6f98dc3f20b9b525af3cdb2b35e0d6af5628e16cdd60465bd952419 (SHA-256)

Docker images

Nightly and stable Docker images are available using selected backend Prolog compilers.

Older versions

Older releases are available here (but note that time stamps do not match the release dates due to all the moving of these files between servers along the years).


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