Rails Before Trains, Part 3: Lightning, Rebuilt for Every Asset

By apltang · November 9, 2026

Part three of a four-part series on RGB++ and Fiber Network, the two technologies Nervos Network is betting on to make Bitcoin assets programmable and instantly payable.

Disclosure: one of this series' authors builds Cellula at LusoCryptoLabs, the studio discussed in Parts 3 and 4, which has an active Community Fund DAO proposal that this series references. The authors hold CKB. This series presents information, not recommendations, and nothing in it is investment advice. Part 1 explained how RGB++ pairs Bitcoin UTXOs (Unspent Transaction Outputs) with Cells on Nervos's CKB (Common Knowledge Base) blockchain, and how a "leap" moves an asset from Bitcoin to CKB without a bridge. Part 2 showed the record: a fast launch in April 2024, a steep fall in activity after the token wave, and steady building underneath. What RGB++ assets lack is a reason to move. This part is about the network that was built to give them one. The bar tab Blockchains are slow and expensive for small payments, for a simple reason: every transaction has to be recorded by everyone. Paying for a coffee on Bitcoin means waiting for a block (around ten minutes) and paying a fee that can exceed the coffee. The solution Bitcoin developers settled on is the payment channel . Two parties lock some money into a shared on-chain account. From then on, they pay each other by exchanging signed updates — each one saying "here is the new split of the money" — entirely off-chain, as often as they like, for free. Only the opening deposit and the final split ever touch the blockchain. Think of it this way: a bar tab. You open it with your card, order all night without paying each round, and settle once when you leave. Channels become a network when payments can hop. If Alice has a channel with Bob, and Bob has one with Carol, Alice can pay Carol through Bob — safely, because each hop is paid only when the final recipient reveals a secret before a deadline. If the secret never appears, everyone's money comes back. (The technical name is a hash time-locked contract; Fiber's software calls them TLCs.) That is the Lightning Network , live on Bitcoin since 2018. Today it has roughly…