Ruismaker is an indie music software label run by Dutch developer Bram Bos, focused on instruments and effects for Apple's iOS and iPadOS platforms. Bos has been involved with audio software since the mid-1990s, when he created the early shareware drum machine Hammerhead, and the Ruismaker brand reflects a continued interest in compact, idiosyncratic tools for electronic music production.

The catalog spans drum synthesis, sequencing, sound design, and modular-style instruments, almost all delivered as Audio Unit (AUv3) plugins that run inside hosts like GarageBand, AUM, and Cubasis. Notable releases include the original Ruismaker and Ruismaker FM drum synths, Ruismaker Noir for analog-style drums and rhythmic bass, the Rozeta suite of MIDI sequencers, the Ripplemaker modular-style synth, the Troublemaker bass synth, the Mozaic scriptable MIDI environment, and creative effects such as Gauss field looper and Skulptur filterbank.

The products are known within the iOS music community for emphasizing real-time synthesis over sampling, lightweight CPU usage, and unconventional approaches to sequencing — particularly the Euclidean and probability-based sequencers in the Rozeta line. Ruismaker apps have helped popularize the AUv3 plugin format on iPad and are frequently cited in coverage of mobile music making on outlets like MusicRadar and discchord.

Ruismaker has 3 products cataloged on Equipboard, including Synth Plugins and Drum Machine.