minised

If you're in need of a smaller, cheaper, and faster SED implementation, then you should check out minised. This software is often used in Minix, and it was also previously used in GNU until they created their own sed based on an extended (and some would say over-extended) regexp package.

For embedded use cases, Eric S. Raymond's minised was found to be incredibly useful - particularly when used with dietlibc. However, the software did have several bugs and was no longer under active maintenance.

Thankfully, several fixes were made and minised is now being actively maintained. Further speedups have been added, along with a real test suite to quickly and easily uncover any regressions. Overall, minised is a solid option for those in need of a lightweight and efficient SED implementation.