Codebase DelphiDoom 0.1
Developer(s) Jim Valavanis (Jval)
Initial release (2021-09-30, 19 months ago)
Latest release (2021-10-03, 19 months ago)
Development status Active
Written in Pascal
Target Platform Windows
License GNU General Public License v2+
Website SourceForge
Source Repository



DoomXS, short for Doom eXtra Small is a source port developed by Jim Valavanis (Jval) developed from a very early version of Jval's other port, DelphiDoom. DoomXS serves as a minimalistic port in nature, in which it intends to fill in the absence of a minimal source port of Doom developed in the Pascal programming language and which has low system requirements. It can run on Windows XP and 128 MB of RAM.

It includes a launcher, called LaunchXS.


DoomXS is based on a very early version of DelphiDoom, namely version 0.1 released on October 15, 2005. It was in development since early 2021 with the first release being version, released on September 30, 2021. Development was discussed in a Doomworld thread titled: "DoomXS - eXtra Small source port."[1].


limit                         : old    * k   = new
visplanes[MAXVISPLANES]       : 128    * 2   = 256
SAVEGAMESIZE                  : 180224 * 5.1 = 942080
vissprites[MAXVISSPRITE]      : 128    * 2   = 256
  • Other limits, such as MAXDRAWSEGS, MAXLINEANIMS and MAXPLATS remained unchanged
  • MAXOPENINGS relies on a implementation seen in a Doomworld thread titled: "Reasonable static limit for MAXOPENINGS? "[2]
  • Support for DOOMWADDIR and DOOMWADPATH environment variables
  • Low hardware requirements
  • No zone memory allocation at startup. This allows DoomXS to launch instantly
  • Launcher application called LaunchXS
  • Small codebase, making it an ideal starting point for Pascal programmers

External links[edit]


  1. Doomworld forums thread
  2. Doomworld forums thread
Source code genealogy
Based on Name Base for
DelphiDoom 0.1 DoomXS Active