Addressing Bitcoin’s Gas Issue Without a Fork | Opinion

In this article, we explore how OpNet proposes to tackle Bitcoin's limitations on executing smart contracts without relying on a secondary token or requiring a network fork. By utilizing Bitcoin's existing fee market for transaction settlements, the aim is to facilitate smart contract interactions seamlessly.

Key Takeaways

Bitcoin's Fee Structure: While platforms like Ethereum and Solana have their own fee assets (ETH and SOL), Bitcoin's fee market is already well-established with block space auctions in satoshis per byte.
Need for Execution Environment: Bitcoin lacks a way to meter computation, which is why many smart contracts operate on separate layers, complicating interactions with its ecosystem.
OpNet's Solution: OpNet proposes a system where smart contract execution can occur outside Bitcoin but utilizes BTC for all fee payments. This maintains familiarity for users and avoids the complexity of adopting additional tokens.
Simplified User Experience: The OpNet approach streamlines the contract calling process, making it feel more like traditional Bitcoin transactions, thereby reducing the learning curve associated with different fee economies.

We enable Bitcoin-native gas for smart contracts, routing execution through a VM while settling and pricing fees directly in Bitcoin’s existing fee market

Understanding Bitcoin’s Limitations

Every smart contract platform has its fee structure inherent in its design. For instance, Ethereum operates with ETH, whereas Solana uses SOL. However, Bitcoin presents unique challenges. Users often find themselves relying on alternative networks to execute complex applications. Platforms like Stacks require fees in STX, and while EVM-friendly Bitcoin layers may claim to use BTC as the gas token, they often just represent it within their own environments.

Bitcoin features a robust fee market, where users bid for block space measured in satoshis per byte. Miners prioritize transactions based on these fees, making Bitcoin simple and resilient. The question arises: could smart contract interactions be initiated and settled as standard Bitcoin transactions, using BTC for fees? OpNet aims to answer that question.

Execution: A Missing Piece

Bitcoin's fee system excels at pricing block space but lacks a mechanism for measuring computation. The scripting language, Bitcoin Script, was intentionally designed to be stateless and not Turing-complete—lacking loops or unbounded computation—to allow for predictable validation across all nodes.

This limitation has pushed many solutions to place smart contract execution on separate systems that measure computation on their own, typically requiring another fee asset (like STX). A more effective approach would enable users to stay within Bitcoin’s native fee market while allowing for external execution.

A New Way of Contract Interaction

OpNet introduces a novel interaction model, differing from standard approaches by following a simulate-then-spend flow. Users' apps first call a contract method in simulation, which then routes the request to an OPNet node that executes the method and returns a CallResult (including fee estimates) before broadcasting anything to the Bitcoin network.

If the call changes the state, the CallResult gets turned into an execution request. At this point, a Bitcoin transaction is generated, signed, and sent to the network. Notably, OpNet still meters computation but in terms of satoshis—for instance, estimating SATS Gas and processing refunds—all within Bitcoin’s economy.

Cleaner Processes with Familiar Incentives

Adopting this system means users no longer need to engage with a second fee economy just to use applications. On Bitcoin, users are already accustomed to paying fees for block space in satoshis per byte, which provides familiar ground when executing contract calls as Bitcoin transactions.

Additionally, OpNet’s design embraces standard Bitcoin functions, making it easier to manage UTXOs, provider connections, and even cold storage signing. This allows for smart contracts to be executed within a Wasm runtime, written in AssemblyScript, achieving an expressive logic akin to Solidity without the complexity of Bitcoin Script.

BTC as Gas: A Viable Option

The common perception that BTC cannot serve as a gas token often stems from the belief that the base layer must meter computation. However, Bitcoin effectively meters block space and settles value. The solution proposed involves handling execution through a virtual machine while ensuring state-altering interactions are routed as standard Bitcoin transactions with fees in satoshis.

Overall, the prospect of BTC functioning as gas could become a reality. By keeping fees within Bitcoin's native ecosystem and utilizing a WebAssembly-based contract runtime, the focus remains on simplicity and efficiency, sidestepping the introduction of separate token economies.