| Operating system | Developer | First release | License |
|---|---|---|---|
| Nut/OS | Ethernut | 2000 | BSD licenses |
| RIOT | Martin Lenders, Benjamin Valentin, Alexandre Abadie | — | GNU Lesser General Public License, version 2.1 |
| Tock | Brad Campbell, Amit Levy | — | Apache Software License 2.0, MIT License |