Update the list of solvers in the readme

README.md

@@ -34,6 +34,7 @@ The benchmark comes with standard and community test sets to represent different
 | [MOSEK](https://mosek.com/) | ``mosek`` | Interior point | Sparse | Commercial |
 | NPPro | ``nppro`` | Active set | Dense | Commercial |
 | [OSQP](https://osqp.org/) | ``osqp`` | Douglas–Rachford | Sparse | Apache-2.0 |
+| [PIQP](https://github.com/PREDICT-EPFL/piqp) | ``piqp`` | Proximal Interior Point | Dense & Sparse | BSD-2-Clause |
 | [ProxQP](https://github.com/Simple-Robotics/proxsuite) | ``proxqp`` | Augmented Lagrangian | Dense & Sparse | BSD-2-Clause |
 | [qpOASES](https://github.com/coin-or/qpOASES) | ``qpoases`` | Active set | Dense | LGPL-2.1 |
 | [qpSWIFT](https://qpswift.github.io/) | ``qpswift`` | Interior point | Sparse | GPL-3.0 |