Platformio advantages

I need to implement a little smart city project, what platformio can provide to me exactly? is it totaly free?

Have you seen this page A professional collaborative platform for embedded development ยท PlatformIO ?

Cross-platform build system, PlatformIO IDE for Atom and VSCode, library manager, continuous integration, and other things are FREE. Those are licensed under Apache 2.0 license.

Premium support and a few extra features from PlatformIO Plus are paid.

Feel free to ask other questions.