Fuel primer: UTXO-based parallel execution and the FuelVM
Thread812 words
Primer on Fuel as a modular execution layer with a UTXO model and strict access lists enabling parallel execution, plus the Sway language, testnet status, team background and funding. Compares to Solana, Sui and Aptos parallelism.
Key claims
FuelVM runs parallel execution for non-overlapping contracts
Fuel can run as a rollup, Celestium, sidechain or monolithic chain
Fuel Labs raised $81.5M across two rounds
0/ execution layers are a core building block of the modular design stack
a super exciting modular execution layers is definitely Fuel by @fuellabs_, a super scalable & flexible solution with its own VM supporting parallelized tx execution ⚡️
a primer 🧵 on #Fuel (0/27) 👇
1/ since I have covered the modular design space in a lot of depth already, I won't go into the details here again
if you need a recap, check out this thread
x.com/expctchaos/status/1601534426592071681
2/ but basically, DA, consensus and execution are unified in one single layer in monolithic blockchain networks (e.g. $ETH)
3/ in modular architecture these layers are stripped apart and (at least) execution is separated from DA/consensus
4/ so, what is Fuel by @fuellabs_?
#Fuel is a modular execution layer solution that can be operated in different configurations. #Fuel be configured as a monolithic chain, a rollup on $ETH, a #Celestium or a side-chain
the below graphic summarized Fuel's modular configuartions
5/ moreover, @fuellabs_ has developed a custom virtual machine, the #FuelVM, that allows for parallelized transaction execution, thereby overcoming one of the core limitation of #Ethereum's virtual machine (EVM)
6/ @fuellabs_ defines parallel tx execution as follows:
x.com/fuellabs_/status/1523671481690980353?lang=en
7/ parallel tx execution is a powerful feature and many newer gereation blockchains have tried to overcome this EVM limitation by designing their own VMs
8/ the @solana VM for example sorts incoming txs to run the non-overlapping txs in parallel across multiple cores
this is only possible due to $SOL's special account-based VM which requires txs to describe all the states they will read or write while executing
9/ another example is @SuiNetwork that uses a custom data model, in which data is organized into objects that can either have a single or multiple owners, thereby allowing its VM to process txs in parallel
10/ finally, @Aptos_Network has also built a highly efficient, multi-threaded, in-memory parallel execution engine that should be able to execute over 160k non-trivial Move (domain-specific language) txs per second
10/ but back to #Fuel, which is based on the unspent transaction output (UTXO) model (rather than account-based) to make use of strict access lists in combination with a custom VM to enable parallel tx execution, where non-overlapping contracts can be executed in parallel
11/ but why is this parallel execution important?
well, FuelVM’s design enables new use cases that can’t be feasibly built on the EVM (such as orderbook DEXes)
12/ for a more detailed comparison of FuelVM vs. EVM see below
fuellabs.github.io/fuel-docs/master/vs-evm.html
13/ additionally, the #FuelVM instruction set has been designed specifically to be both expressive & fraud-provable within the #EVM
14/ the latter is achieved through support for trust-minimized light clients
trust minimized light clients & shared data availability enables trust minimized bridges to other modular execution layers, something impossible to achieve between monolithic L1s
15/ finally, in line with the modular thesis, #Fuel has been designed with the express goal the using $ETH as a settlement layer, consensus & DA layer for its execution environment
16/ @fuellabs_'s approach to $ETH scaling is summarized in the below graphics
17/ moreover, the #FuelVM has its own domain-specific programming language. #Sway supports built-in top-level contract storage as well as ergonomic & safe contract programming standards from #Solidity, with the syntax, borrow checker & safety-first semantics of #Rust
18/ interestingly, #Sway’s compiler is uniquely able to audit smart contracts, catching issues that typically auditing firms are hired to discover, which is a pretty sick feature
won't entirely replace smart contract audits though
19/ the #Sway language is already gaining quite some traction
find resources below:
fuellabs.github.io/sway/latest/
fuellabs.github.io/fuel-docs/master/fuel-toolchain.html
17/ but what's currently going on at @fuellabs_ you ask?
well, after launching beta-1, the first public #Fuel testnet back in September, the team has recently announced the launch of beta-2, the next iteration of the public testnet
fuel-labs.ghost.io/announcing-beta-2-testnet/
18/ beta-2 intrpduces a number of new features as summarized below
19/ but what about applications on #Fuel you ask?
#Fuel has already been gaining quite a bit of traction with >10 projects already building on it
a list of confirmed projects can be found here
github.com/FuelLabs/awesome-fuel#projects-building-on-fuel
20/ on beta-1, @fuellabs_ also has a Uniswap-style DEX demo live if you fancy trying
fuel-labs.ghost.io/introducing-swayswap/
21/ so finally, who is behind #Fuel?
@fuellabs_ was founded in 2019 by @jadler0 & @iamnickdodson. Adler has a background in Electrical & Computer Engineering. He was also a blockchain researcher at @ConsenSys where he pioneered optimistic rollup designs
22/ moreover, @jadler0 is the co-founder and chief research officer at @CelestiaOrg, which I have covered in depth here
x.com/expctchaos/status/1535970188012572672
23/ @iamnickdodson on the other hand was one of the earliest #Solidity coders on #Ethereum. He later joined @ConsenSys where he worked on crowdfunding & governance applications before he left to co-found @fuellabs_ with @jadler0
24/ @fuellabs_ is well funded and has successfully raised a total of $81.5 million in two funding rounds
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