I develop and release all of my open-source software projects for free, and are all licensed under WTFPL, GPL, MIT, or MPL.
However, my "free time" is not free at all. If some of my works are usable to you or make you happy, please consider to donate (and tell me which project helps you, if can) to reduce my business hours to make more free and open-source projects for you and this world.
Attention: Donate only if you feel happy; it is totally voluntary. I always try as possible as I can to make good project because I need, and wish my work could also be helpful to others. If you donate, I will be glad and grateful, but I cannot provide any gurantee or warranty for the projects even if you do this.
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PatreonThanks for your contribution and happy hacking!