Ok, thank You for Your answer, mayby I was not very clear in describing our problem, so I will describe it again in more details... We wrote a storage engine (implementing ha_xx.cpp/*.h)... It is dynamically linked with MariaDB Database and it works only with installed MariaDb Database. Our code use some MariaDB/MySQL classes like ConditionPushdown Items and func classes... Problem which we try to solve, is how to sell our custom storage engine with MariaDB database... 1. Which version (license) should buy our customer (company customer) on MariaDB Database ?? - can they use it free or should they buy any version (which one ??) 2. Which licence (if any) should we use to sell such custom storage engine ?? - Should we pay for using MySQL/MariaDb classes in our code ?? - which license should we use (bought from Oracle or MariaDB if any is needed) to sell our product (storage engine) without sharing the code, just selling binary files ?? Thanku You for Your quick reply... Mateusz Matan -- ___________________________________________________________ Mateusz Matan IT Security R&D Department, C/C++ programmer ComArch S.A., Al. Jana Pawła II 41d, 31-864 Kraków tel: (+48 12) 684 8411 e-mail: Mateusz.Matan@comarch.pl