The player can advance with any working solution to each problem, but is challenged through leaderboards to produce a machine that does the task in the shortest time, with the lowest cost of materials or the smallest occupied area.

Opus Magnum is based on The Codex of Alchemical Engineering, one of the earliest Flash games made by Zach Barth prior to establishing Zachtronics.

The goal for most puzzles is to deliver a fixed number of target output products, thus testing the machine's operation over several cycles.

[1] While Barth led the programming effort, Matthew Burns was the writer for the game's dialog and composed its music.

One user had produced a looping GIF of one of their factory solutions, which Barth and his team found strangely satisfying.

This led Barth to design Opus Magnum to be inherently GIF-able with seamlessly repeating loops that looked appealing and required little other context for viewers to understand.

[7] While GOG representatives initially claimed that the game had failed the site's internal curation system, and that its user base would not want to purchase it, on January 31, 2018, the site reversed its position after a fan outcry, and began offering it for sale, stating that their initial perception of the game's quality and community demand had been incorrect.