If you are developer looking for creating new forms of RGB smart contracts or integrate RGB into your software, check out developer guidelines:
Simple RGB contracts can be created in Rust (using handy macros). More advanced contracts will require writing code for AluVM in AluAssemblye language. We also work on a new high-level language called Contractum, with its first version release targeting end of the year.
Want to let your users access RGB assets & smart contracts? Integrating RGB is simple as using one of existing SDKs in your project and working with JSON data structures. Check what libraries exists for RGB integration today, provided by several independent teams and companies.
RGB is much more complex than simple bitcoin applications; to unlock its true power in creating the world of Bitcoin Finance (#BiFi) it is important to understand its terminology and internal architecture in details. A good starting point can be through multiple RGB learning resources.