Alekos Filini: The Origins of RGB
At the Tuscany Lightning Summit 2026 in Viareggio, Italy, Alekos Filini, the developer behind the first prototype of RGB Protocol on Bitcoin, looked back at the early days of the project and shared his view on assets on Bitcoin and on layer 2 protocols.
Watch the full interview in the video below.
Note: the interview dates back to May 2026 and reflects the views of the speaker at the time.
In Brief
- Origins: Alekos Filini picked up an early RGB design from Blockchain Lab and wrote a proof of concept in Python, then his first Rust project
- Goal: assets on Bitcoin, with a more private model than the account-based one of Ethereum and stablecoins as the number one use case, then and now
- Layer 2: no single winner, and Lightning as the interoperability layer across Ark, Spark and other protocols
Alekos Filini and the First RGB Code
In 2017, at the time of the ICO craze, almost every asset project ran on Ethereum and the EVM. In that context, Alekos Filini joined Giacomo Zucco at Blockchain Lab, attracted by the research environment of the lab rather than by a specific plan for RGB. Then, at some point, Giacomo Zucco told him about a project designed with Peter Todd and Riccardo Casatta, which the team had set aside for lack of resources for the coding work.
Since he had some free time in his schedule, Alekos Filini took over the project: first, he wrote a proof of concept in Python, and then an implementation in Rust.
Assets on Bitcoin and the First Design
From the start, the goal was assets on Bitcoin, that is, moving anything other than satoshis on top of Bitcoin. Stablecoins were the obvious use case, together with tokenization, although real-world tokenization always comes with complications. Moreover, in his view, the account-based model of Ethereum offers terrible privacy; for this reason, the team saw RGB as a research project to emulate ERC-20 assets on a better and more scalable model on Bitcoin. Even now, stablecoins remain the number one use case for him, since they belong to a sector with proven traction and proven demand; therefore, stablecoins on top of Bitcoin offer a better option than stablecoins on any random, massively centralized blockchain.
Back then, RGB was much simpler: the first design committed data into transactions through OP_RETURN, with no fancy commitment schemes. Today, RGB supports two deterministic commitment schemes, Opret and Tapret, as described in the documentation.
Lightning as the Interoperability Layer
According to Alekos Filini, a single project can hardly deliver scalability, privacy and low fees all together, which is why Bitcoin needs alternatives with different goals: for example, one project with a focus on privacy and another one on the onboarding of new users, even with a more custodial approach. For the same reason, he expects no single winner among layer 2 protocols, although he foresees some consolidation at some point, given their current number.
At the same time, interoperability is key, and for him Lightning works as the plumbing across Ark, Spark and the other layer 2 protocols on Bitcoin. In fact, compared with the more fragmented past, almost everything now has a bridge to Lightning; as a result, people can pay each other across different wallets, architectures and trust models.
The full interview is in the video above. For more videos from the RGB ecosystem, follow @RGB_Bitcoin.
Further Reading
- History of RGB Protocol on Bitcoin: From 2015 to Mainnet
- Stefano Pellegrini: RGB Since Mainnet at Tuscany Lightning Summit 2026
- Interoperability on Bitcoin: Mo Harchegani at Tuscany Lightning Summit 2026
Interview recorded at the Tuscany Lightning Summit 2026, Viareggio, Italy. Video on the RGB Protocol YouTube channel.
