Fans have spent the last three years reversing-engineering Star Wars: Dark Forces' Jedi Engine in order to make the game easier to play on modern machines (as recently spotlighted by Build Engine Aesthetics on Twitter).
According to the GitHub page, the Force Engine, as it is called, is a collaboration between various individuals, including LuciusDXL, Winterheart, and Gilmorem560, who have set out to "add ease of use and modern features" to the LucasArts' classic FPS.
In the past, if you wanted to play Dark Forces on modern machines, your best bet was to purchase a digital copy from Steam or GOG and run it through the emulator DOSbox. Force Engine, however, provides a more bespoke option for players, running the executable with minimal fuss and a ton of additional extras thrown in.
Some of these new features include support for widescreen modes, higher resolutions, a new save system, and a mod loader. This is in addition to the inclusion of full mouselook, an aiming reticle, and "improved Boba Fett AI".
Dark Forces was released in 1995, fresh off the popularity of Doom. As such, it's often been called a "Doom Clone" in a Star Wars skin, but that does a disservice to its incredible level designs and technological innovations over its predecessors. If you want to play an incredible first-person shooter in the Star Wars series, it seems there's no better time than now to give it a chance.
The next step for the team behind Force Engine is support for Outlaws, LucasArts' first-person western that was also developed in the Jedi Engine. That will arrive with the emergence of Force Engine V2.0, per the GitHub page.