Kimai is a web-based multi-user time-tracking application
Profesionalna integracja z Krajowym Systemem e-Faktur (KSeF)
Free & Open Source Invoice App for Freelancers & Small Businesses
FreelancerBooks -Project Management for Freelancers and Agencies
A complete invoice managment solution for Elastix PBX
Software developed for the purposes of czela.net o.s.