  We present a calculation of pion photo- and electroproduction in manifestly
Lorentz-invariant baryon chiral perturbation theory up to and including order
$q^4$. We fix the low-energy constants by fitting experimental data in all
available reaction channels. Our results can be accessed via a web interface,
the so-called chiral MAID. We explain how our program works and how it can be
used for further analysis.
