Sleeptime Markup Language

A new/old markup language.

Sleeptime Markup Langauge (STML) was designed and developed by Mark LaCroix to create all the in-game webpage content for the game Dreamsettler.

STML, as the name implies, is inspired by HTML, the real-world markup language used to create webpages. The system consists of three file types: STML, SSS (Sleeptime Style Sheet), and STINC (Sleeptime Include). The class-based styling system used for SSS works similarly to how CSS does on real webpages, and the include system for STINC was inspired by a feature from PHP often used in the early/mid 2000s.

However, unlike its real-world counterparts, all three "Sleeptime" file types use a shared syntax, making the system much easier to learn and use for players and modders.

STML is both a developer tool for creating Dreamsettler's "fake Internet," and a piece of worldbuilding/narrative design as the in-universe language used by the characters of the game's early-2000s alternate history setting. It was designed to work equally well in both contexts.

In Dreamsettler, players could inspect the code of various pages to discover clues and story points, use it to edit or create pages of their own, and read about its fictional history and development.

Pages can be created using the in-game WYSIWYG "Page Genie" program (also developed by Mark LaCroix) which was inspired by equivalent contemporaneous software like Macromedia Dreamweaver and Microsoft FrontPage, but it was also meant to be written using any text editor, such as Notepad or Visual Studio Code. Either workflow can be used separately or in tandem with the other.

Dreamsettler was cancelled in 2025, but STML survives. Its plugin for Visual Studio Code is available for free on the Visual Studio Marketplace. Additional use-cases for the language and its tools are being explored.