Open Source IF

Open Source IF is interactive fiction that is released together with its source code. This allows other authors to study the source code and see how things were done. Unlike free software, open source software does not necessarily allow you to modify and redistribute the work. (It should be noted that this terminological difference is not universally accepted, as some people and organisations use open source software as a synonym of free software.) Free software Interactive Fiction will not be listed below, since it already has its own page.

Interactive Fiction released as Open Source Software

Creative Commons Licenses

Although the Creative Commons licenses have not been specifically designed for software, they have nevertheless been used for several Interactive Fiction programs.

Attribution-Noncommercial-Share Alike 3.0 Unported

This license allows you to redistribute and adapt the work, as long as you attribute the work in the manner specified by the author or licensor, do not use it for commercial purposes, and release it under this same license.

• The Chinese Room by Joey Jones and Harry Giles, Inform 7. <-- There is no source code available for this.

NonCommercial Sampling Plus 1.0

This license allows you to copy and adapt the work, but only on the conditions that (1) it be used non-commercially; (2) the derivative work constitute a good-faith partial or recombined usage employing "sampling," "collage," "mash-up," or other comparable artistic technique, whether now known or hereafter devised, that is highly transformative of the original; (3) the original work is either only partially used, or forms an insubstantial portion of the derivative work, or the derivative work must be substantially transformed. Please refer to the license for further details.

• Child's Play by Stephen Granade, Inform 7.

Home-brew Licenses

These programs are released under licenses that the author's have written themselves. As such, details may vary and a careful reading of the license text is necessary.

Licenses that do not allow derivative works

For these works, the source code is provided for studying it only: you are not allowed to redistribute any modified versions of the game.

• Augmented Fourth by Brian Uri, Inform 6 (not entirely clear about the issue of derivative works).
• Chicks Dig Jerks by Robb Sherwin, Inform 6.
• Deadline by Marc Blank, ported by Volker Lanz to Inform 6 ("Please do not distribute modified versions of these files.").

Licenses that do allow derivative works

These works do allow you to redistribute modified versions of the game, but place one or more restrictions on the process of changing or distributing that are incompatible with free software.

• The Awakening by Dennis Matheson, Inform 6 (almost free software; you are not allowed to charge for distribution).
• Beyond Zork Example by Allen Garvin, Inform 6 (commercial uses not allowed; based on copyrighted Infocom material, so of questionable legality).

No Licensing Information

There are quite a lot of source code files on the IF Archive that do not come with any licensing information. As such, it is better not to assume that you can use this source code for your own works, unless you get explicit permission from the authors. For ports of a game to another authoring system, this means you must ensure that both the original author and the porter give you permission to use the code.

• Adventure by Will Crowther and Don Woods, ported by Donald Ekman, David M. Baggett and Graham Nelson to Inform 6.
• Adventureland by Scott Adams, ported by Graham Nelson to Inform 6.
• Back to WakeUp by Daniel Roperto, Inform 7.
• Balances by Graham Nelson, Inform 6.
• Beneath: a Transformation by Graham Lowther, Inform 6.
• The Big Mama by Brendan Barnwell, Inform 6.
• Cattus Atrox by David Cornelson, Inform 6.
• Cave by William Stott, Inform 6.
• Caverns of Chaos by Paul Martinez and Alison Castro, ported by lemonhead to Inform 6.
• C.I.A. Adventure by Hugh Lampert, ported by J. Kevin Thomas to Inform 6.
• Competition '99 by Lucian Paul Smith, Inform 6.
• Detective by Matt Barringer, ported by Stuart Moore to Inform 6.
• The Dragon and the Troll by Johan Berntsson, translated and ported by Fredrik Ramsberg to Inform 6.
• ELIZA, adapted by Ricardo Dague to Inform 6.
• A Fable by Stan Heller, ported by Stuart Moore to Inform 6.
• It's a Dog's Life by Mr. WiggleButt, Inform 6.
• Journey to Alpha Centauri (In Real Time) by Julian Fleetwood, Inform 6.
• Rachel has a Bad Day by Sly Old Dog, ported by Roger Pepitone to Inform 6.
• A Tight Spot by Quim K. Holland, Inform 6.