Ed Felten: Arbitrum – The Layer 2 Scaling Solution Increasing Speed and Reducing Fees #448

Transcript

welcome to epicenter the show which talks about technologies projects and people driving decentralization and the blockchain revolution i'm friedrich hans and i'm here with brian fabian crane and today we're speaking with ed felton who is the co-founder of arbitrom which is a road up solution on top of ethereum and we will talk about this um in great detail in just a bit but before we talk with ed about arbitram um we would like to tell you about our sponsors this week so first of all we have gnosis safe so hypnosis safe is a security standard for web3 reimagining the future of ownership and value coordination it works as a multi-signature based smart contract account and is compatible across popular evm chains

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sake wallet is your new favorite multi-chain mobile wallet that puts the power of web 3 at your fingertips in just a few tabs you can take and manage your assets um on over 22 built-in protocols including all major evms non-evms and layer tools like arbitrom stake wallet is adding new features at light speed so you always have the best support across all chains just in the last two weeks they've shipped three tab bnb chain staking in harmony one sticking sec wallet has also um um a pretty good nft support um on mo on on a mobile wallet and you can view all your nfts in one place and it's about to become the first mobile wallet with um

arbitrarium nft support as well watch out for an announcement um at nft new york city on june 20th you can download stake wallet today on ios or android at stake wallet.fi spelled steak like the meat fantastic and it is such a pleasure to have you on thanks for having me ed you um are uh you are an og cypherpunk you have been doing this longer than all of us um tell us a little bit about yourself um and tell us about crypto free blockchain

sure yeah so i've been working in um i've been playing around with software for a long time actually since the 1970s believe it or not and got involved in security and privacy and cryptography research going back to the 90s i spent quite a few years teaching at princeton university and computer science department and a lot of my research there was around cryptography and security and getting into ideas of digital money even before uh this sort of explosion of cryptocurrency started with uh uh you know with satoshi's original um

bitcoin paper um but i got interested in uh crypto currencies in blockchain really early um and started doing research in the area and um yeah that's kind of what led up to uh to arbitrarily but you know over the years i've been involved in a lot of different security things as a researcher and um also um uh maybe surprisingly to folks in this space um as uh working in the government as well so um yeah uh and i think a lot of that has really helped me get a perspective on what's happening now in the crypto space you used to be the deputy cto of the usa so forgive me this question but i'm not

american and what what does what does the cto and the deputy cto get to do sure so basically um yeah as deputy cto i was a member of the white house staff and a senior advisor to the president then president obama and basically the job of the cto and deputy cto is to advise the president and the president's advisors about things having to do with technology so we were not building stuff we weren't running systems we weren't the ones whose pages would go off in the middle of the night if there was some kind of an incident

we were producing words and advice but rooted in an understanding of technology so if you know there was some kind of security breach somewhere or if um there was a policy issue around uh technology then we would work on it so as an example i worked some on encryption policy you know should the government regulate or ban um end-to-end encryption i worked on ai and machine learning um i was one of the folks who drove the national national policy initiative on ai and machine learning back in those days and things like that so basically advising senior government people and including up to and including the president

kind of an amazing job to have and did you do any uh crypto related work as part of that as well yeah i did some um you know this was very early days in terms of government figuring out um thinking about crypto but one of the things i was working on was trying to get people across the different departments of the us government to start talking about crypto and what they should do help help make sure that the different parts of government of the executive branch understood what was going on and uh and we're starting down the road of thinking about what they should do whether it's you know people thinking about should we have a central bank digital dollar

um as well as you know people who did things like consumer protection and various kinds of regulation make sure that they understood what was going on and we're going to take a thoughtful approach to it so i was involved in sort of early attempts to get that conversation going within the us government so i'm curious because you mentioned before that like you know you had to sort of uh perspective on on crypto and blockchain you know that was like maybe different because of you know the work you did before i'm curious if you can talk a little bit more about that sort of you know when you discover bitcoin like what was your perspective and how has it changed as the industry has evolved

yeah so yes let me tell you a little bit about that well that particular that comment of how my working government has um uh has affected my views on this first of all i have been a regulator or i've worked in a regulatory agency i worked at the federal trade commission for a while which was as as their chief technologist which is in the us government is the main uh agency that protects people against uh fraud commercial fraud and scams um and so you know that mindset of how do we make sure that companies are not just stealing from people um you know the the equivalent of something like what in the crypto world would be a rug poll or

some kind of other you know really fraudulent activity and sort of thinking about what do you need to do to help protect people against that and what is the role of government in trying to shut down the bad actors and try to get the money back and give it to the people who it was stolen from um and so i got some perspective from dealing with some of the types of fraud and scams that were going on online in those days that was like 2011 and 12. so then i i did that for a little while then i went back to being an academic and during that academic time um starting around 2012 um is when i 13 is when i discovered bitcoin and got really interested in this this stuff as a

research topic and like questions of how people could protect themselves and how you could know uh that something that some software was telling you was gonna happen was actually gonna happen um was part of that plus just like understanding basic questions like is proof of work incentive compatible that is like does it actually incent minors to behave in a cooperative way which turns out to be a much more complicated question than you might think but anyway then sometimes early on i learned about smart contracts and this idea that you could do run software on top of a blockchain and i thought this was the coolest thing ever um and got really excited about the tech especially what you know it as a vehicle

for uh for building software because i like been involved in and seeing the development or sort of early development of internet and web technology and saw sort of that stuff go through its very early commercial birth and and some growth and some growing pains so i'm like okay this is going to happen with smart contracts this is going to be huge as a software platform um that in turn led me to thinking about well like what are the technical barriers to that technology actually getting used by a billion people and well one of the big technical barriers that seemed obvious at the time was scalability and that in turn is what led

to the work that sort of the birth of arbitration in early 2014 um sort of as an attempt to try to solve the problem of how to scale this technology up so that it could get the use that i figured that i think a lot of people did at the time it that it was going to demand so so let's talk about arbitrary in just a bit that but basically thinking back about the very early p2p community or the pre-blockchain p2p community there are large reservations um or you know holdouts um that are very skeptical of blockchain technology as a whole why do you think that is uh well so i think it's a bunch of

things um and we saw some of this with the early like the early web technologies um i mean we have to admit that some of the things that go on in this space are basically just scams they're people who are um who are dishonest or people who um think they're honest but are actually doing things that are really dangerous so this idea that it's kind of a you know a wild west that people are doing all kinds of risky and scammy and dangerous things along with a lot of legitimate and exciting building that pretty much reminds me of the early internet days and there was a bunch of skepticism there but i think there's extra spec skepticism in our space

of our space and it's for a bunch of reasons i think like there's a natural skepticism about new tech areas especially ones that have a lot of venture capital pouring into them um there's a natural skepticism about any you know about finance and finance as a field and the kind of people who hang out in that space and in the tech space right like right now tech people are kind of out of fashion the idea that um that like people who are building and running tech things are like dangerous and anti-social and the tech industry might not be good for the world like i don't buy that at all but it is kind of a fashionable view and i think we get some of that

plus we get some of what happens because we're new and people are trying a lot of a lot of things and some of them fail um and then i think there's this other dimension to it which i can't quite explain that it's kind of become fashionable in some circles to say that like everything happening in the blockchain space is just a giant ponzi scheme um which i think to anyone who's in the space and paying attention is obviously wrong but you know i think it's become fashionable in some circles to say this is all bogus and nothing nothing interesting going on but you know i think could not be further from the truth there are there are some people in the space who are liars and dangerous and so on but um

there's also a ton of people doing really interesting and solid work um and you know and that's what that's what will last just like in the early internet there are a lot of people trying crazy things and nobody remembers them but you know people do remember those who actually built valuable stuff over time yeah absolutely well let's let's talk so you mentioned 2014 right you had this kind of early scaling work you did that you know kind of later became arbitrary can you talk a little bit about you know what was that 2014 project yeah well so it started just with the idea the idea of which i think today we

would call layer two which was that you could have something that was basically a ch that if you had a base chain which had smart contracts or something like it on the base chain that you could build a chain above it or off on the side and then anchor the security of that second chain sort of in the first chain so you could have this thing where you could have a chain running off on the side that it would use only a little bit of the capacity of the base chain but if you did it right you could sort of inherit the security of the base chain so that was kind of the key idea to move almost all of the work off the main chain but have just enough

functionality on the main chain to maintain security and the key idea that enabled that was what's now called interactive fraud proofs which is basically a way of resolving a dispute between two parties about what is the correct outcome of a computation and do that in a way that is that involves very little work sort of on the base layer in early 2014 is when that idea sort of came along and for most of 2014 i had a diagram on my whiteboard in my office at princeton that had sort of a dot was a diagram that sort of showed the steps of an interactive fraud proof um and then in the fall of 2014 semester there was one of my colleagues arvind

narinan taught a course on um on blockchain techno on blockchain tech and all the students in the course had to do a course project where they would design or build something so a group of i think six students got together and day five or six and they decided to build a version of this thing that i had on my whiteboard um and um one day sitting around the table we came up with the name arbitrary for it and so they built a kind of very early proto arbitram which didn't quite work and didn't have the features of you know anything like today's system obviously you know over eight years the system has evolved a lot um but but basically the first version they built in fall of 2014 and you can

actually go on youtube and if you search for something like arbitrary princeton students or something like that you'll see a video of their course presentation at the end of that semester that they gave in january of 2015 and they talk about you know basic ideas that you might still recognize in arbitrary today so that was the very first version of arbitram what was the base layer that it was built on back then well that was the funny thing there wasn't really a base layer we had to just assume that there would be one so the idea back then is you had to build something that kind of simulated the base layer um

yeah so this was before ethereum was uh you know was at the point where you could use it um so um yeah there wasn't really a base layer at that point we knew there was going to be one and that you know we had a design that what could be sort of agnostic as to what base layer it was on you know much later when we decided to commercialize the technology when we started our company we said okay ethereum is the place to go for a lot of you know for a lot of reasons we can talk about later maybe um yeah but initially it was agnostic and we just had a kind of simulated base layer underneath i'm curious what's this idea of like a kind of like a layer two

was this like the first time this came up i mean i know lightning network wasn't like that much later but i think it's maybe 2015 or something that the lightning were there other ideas like this around i mean i don't know of the idea of a layer two being out there before i would hesitate to claim i was the first one to think of it but um but you know because good ideas pop up everywhere and repeatedly um there was something not too different from there was a much less efficient and probably less practical thing that was related to

the interactive fraud proofs um that was in um uh academic paper from 2011 from by ron kennedy and some other people um called a referee delegation of computation um so i would say you know this sort of emerged out of a cloud of ideas that were out there and you know as a researcher i often felt like there were ideas swimming around in my head trying to find the right way to latch onto each other to make a you know like a design or a solution and i feel like that's kind of what happened at least for me at that time that there were ideas that people were talking and thinking about in like this

particular combination of ideas and the way that it could you could use it to scale smart contracts sort of gelled around that time so anyway so 2015 right the students finished this project and so we had this thing which is where a sort of early pre-prototype proof of concepts things sort of existed and this is where this this sort of story evolution of arbitrary collides with my story about working in government because um my sort of my life took a detour not long after that which is i got invited to go work at the white house and so i did you don't say no to that

kind of offer um and so arbitration just kind of got put on the shelf um during the whole time you know being like a somewhat senior member of the white house staff is the most all-consuming job i've ever seen and so there's no time for anything else um afterwards in uh january of 2017 at the end of that administration they pushed all of us staffers out the door and i went back to being an academic and um while i was there trying to sort of get my bearings again and figure out what i was going to do for research these two one day these two grad students harry kaladner and stephen goldfeder walk into my office and say um hey

remember that arbitrary thing from before you went off to the government and we're like oh yeah that was i thought that was fun and so they were they said let's do that again so like they came to me and said they wanted to work on this project with me and like turn it into a more sort of mature and complete system um and a year and a half later we were the three co-founders of you know of off chain labs which is a company that's built the commercial version of arbitrage so that was sort of the revival of our return which was sort of really came from the two of them coming back and sort of reminding me of this and saying we should do this and then one thing led to another we had an academic paper that we published in 2018

um summer of 2018 and then like almost immediately afterwards before we formed the company because it looked like something that had commercial potential and we wanted to like actually get it out there into you know the hands of of users yeah super interesting and basically i think the stress level of being a crypto founder is uh put put into perspective by having you know an even more stressful job beforehand so i think you played this very well yeah there's like there's frankly no comparison because what we do today is important it's important to us it's important to a lot of other people we take the responsibility of building this technology really seriously

but you know the the stakes when you're an advisor to the president of the united states are higher that like many of the decisions that he made or issues he worked on were literally life and death for other people and being involved in responding to issues like you know terrorism and or even you know even discussions around economic policy where you're talking about do you know where the decisions that are getting made can affect whether tens or hundreds of thousands of people have jobs um whether people lose their homes and have health care and all those sorts of

things right um being around people who deal with those issues every day it makes the the problems of a of a startup founder seem see mild by comparison i often tell people that that job completely recalibrated my sense of of stress so you know this seems like a breeze by comparison i'm happy to hear that i will try that in my next life um so um let's let's talk about how you guys set it on using ethereum as a base layer yeah yeah so you know we knew we wanted to use we wanted to pick a base layer and ethereum seemed like

so and of course this is one of the steps from being an academic prototype where you say hey look this is a super general thing it can run on top of any base layer that has you know basic smart contract functionality but it's going to be a product it's got to run on an actual thing and so ethereum seemed like the obvious choice for a bunch of reasons first of all you know it was it had had and still has the most developers and the most users and so on of smart contract based technology we really liked the ethereum community and sort of the way that it's governed and the sort of the openness of it and we really liked it as a community and we

felt like it was a place where we could be comfortable where the sort of the sort of experience we were trying to build would be consistent with what the ethereum community was going to do and we've always from the beginning seen what we're doing as not sort of as a complement to ethereum to try to make ethereum better so it seemed really obvious from the beginning that ethereum was where we wanted to be that we had to focus on something and um and pretty much every criterion um ethereum looked like the best place to be we also thought you know just from a pure sort of um in terms of like the the need for what we were doing that ethereum was going to be the system that hit

congestion and an increasing in transaction fees uh first uh partly you know partly because of um you know technical attributes of ethereum but also because just there were so many people there and the community was growing in such a nice way cool yeah that makes a lot of sense well let's uh let's talk a little bit about roll-ups because i think roll-ups is something that you know most listeners will like have some kind of awareness of you know they've heard of it but at the same time probably don't quite understand it so can you explain what are roll-ups sure yeah so roll-up is a

uh is a chain that operates as an independent chain but that has its security anchored in an existing big chain in our case ethereum and so the key idea is that we keep the data the sort of input data of the transactions what are the transactions that users submit and those get recorded on the ethereum chain um and but we moved the computation and the storage basically the heavy lifting of operating the chain off onto a separate place onto the separate arbitrary chain that has its own nodes and its own uh its own systems um participating in it

um but the key thing that makes rollups i think really nice is that they're at least ones like ours is that they can operate trustlessly meaning that all the data that you need in order to be a first class actor in the system in order to know exactly what the chain has done and participate fully in the protocol that's all recorded on the ethereum chain and then the settlement of uh of transactions that happen on the roll up those are also somehow settled back to the l1 chain so that the ethereum chain knows what is the state route of our layer 2 chain so what that means is

you get better performance and lower cost because we move a lot of the stuff off the ethereum chain where gas and transactions are pretty expensive because there's a lot of demand but we still can anchor the security of the roll-up chain in ethereum so if you trust ethereum and you believe at least one member of our community is honest then you can trust our chain as well so that's sort of the value proposition not only of arbitrary but a rollups generally you can inherit the security of the layer one ethereum chain but at the same time you can move most of the work off of it and so transactions are a lot cheaper and you can have more capacity so just to

kind of clarify this so let's say today i'm sending a transaction on ethereum you know i just send you on ethereum and check on ether scan okay that's just my transaction but in this case i would send the transaction you know to a bunch of arbitrary nodes well to one yeah to one arbitrary node yeah so let me talk about the user experience of this right so if you're using ethereum right like you said you're maybe using you're using a wallet um and your wallet has the address of some nodes a url of some node um in it so that when when you approve a transaction your wallet puts your puts your signature or your address's signature on it your wallet will send that to to an ethereum node right and then the

ethereum magic happens and sometime later you get back or you see you see the result of your transaction right if you're using arbitron um it's basically the same user experience in a sense you can use the same wallet and you um instead of putting the address of an ethereum node instead of your wallet having the address of an ethereum node and sending the transaction to the ethereum node your wallet has the address of an arbitrary node and it sends the transaction to the arbitrary node so we've done the work to make arbitrum compatible with ethereum so that the same transactions will run on it you send literally the same bits that you your wallet would have sent to the ethereum node it can

send to the arbitrary node and someone who's developing a smart contract to run on arbitram they'll send literally the same bits that they would send to an ethereum node in order to deploy the contract so you achieve a level of compatibility in the user experience what happens after your transaction gets to that node is a bit different and i can walk through kind of what are the steps um if you like but in terms of user experience or developer experience it should it's designed to feel just like using ethereum except that transaction fees are lower and response time is shorter so yeah so if you so let me walk through

what actually happens with your transaction there's kind of a front end and a back end of a system like arbitrary there's sort of two phases the first one is sequencing and that's all about the system receiving your transaction putting all the transactions into order you know one in front of the other and then recording those ordered transactions and then there's the second phase which is the execution and settlement phase which is the which is the phase that figures out what is the result of executing those transactions in the sequence that came out of the first phase right so but let's talk about like a typical transaction so user makes a transaction using uh

some user interface on their wallet eventually they click that button on their wallet that says to to send the transaction right so that puts their digital signature on the transaction the transaction gets sent to an arbitrary node the arbitrary node will forward that transaction automatically to the arbitrary sequencer which is a component that's receiving transactions from all over the place and the sequencer emits an ordered sequence of transactions so it publishes a feed of um a real-time feed of transactions and so um the node that you sent your transaction to might be subscribed to that feed so the node will see your transaction in the feed see what

the result is and send that back to you immediately it's usually around one second so and and users love this this part of the system right um so then the sequence of the arbitrary sequencer will later take your transaction and a bunch of transactions that came in around the same time and put them all into a batch which is just like a bunch of the data of all the different transactions packed one after the other it will compress that batch using a is using you know a common compression algorithm and it will take that compressed batch and post it on the ethereum chain um as ethereum call data

and the reason that's important is that that data is that what the transactions were and what order the sequencer put them into is like fully recorded and notarized on the ethereum chain so everyone has access to it and there's no dispute about possible about what what the transactions were or in what order tell us about the sequencer sure so yeah so the sequencer right now is a centralized component that our that we the arbitrary team run um and the sequencer follows a first come first serve policy for putting the transactions into order that is first transaction to arrive whichever transaction arrives earlier gets to be

earlier in the ordering and so currently um it's the sequencer is trusted to establish an order on the transactions but it's not trusted for any other purpose in particular the sequencer can't create transactions out of nothing because transactions have to be signed by the user right and the sequencer can't forge those digital signatures the sequencer could try to throw some transactions away but there's an there's an anti-censorship mechanism that people can use to force their transactions into the sequence even if the sequencer isn't cooperating the sequencer currently is a centralized component and we've you know it's in our roadmap to decentralize the sequencer so

that you have a committee of sequencers and as long as a majority of those are honest then you get a fear of your sequence yes just one question i have on this is so the transaction the transaction information right it gets put into i guess each ethereum block or it gets put into the ethereum chain you know on some regularity but as an arbitrary user does that mean i also have to sort of you know like the confirmation or like the finality of my transaction is like when it gets recorded on ethereum or can i rely on it before that yeah so that you get definite finality when your

transaction is recorded on ethereum and so the and and the main time factor there is just the ethereum finality time right so if you're going to wait for say 20 ethereum blocks for finality you know that's about five minutes so all the sequencer also publishes this real-time feed of transactions and that's the sequencer's promise that it will record the transactions in that order and so if you trust that promise then you can use the res then you can use the sequencers real-time feed to uh to know what the result of your transact what the ordering of transactions will be

and your transaction will show up in that feed in about a second so most in practice most um applications choose to have their uh choose to have their ui rely on that sequence or feed but you are trusting the sequencer's promise of order but again it's only ordering it's not what the transactions are that you have to that that you'd be trusting there so that's your choice basically you can get one second soft finality which means finality unless the sequencer is lying to you sequencer's making you a promise to record the data in that order and the sequencer always has the power to keep that promise but fundamentally you're relying on it to keep the promise if you're relying on

that fee or you can wait until the transaction sequence is recorded on the ethereum chain and that is going to take as long as ethereum finality does so the sequencer then sends the compressed data to the ethereum main chain um so i mean it has to pay gaps for that and basically there's no there's no way of forcing um validators or miners to include a transaction right so how do you guys make sure that you can you can definitely have that call data on every ethereum doc yeah so

the first so this gets to what happens in the second sort of the back end phase or the execution phase of the protocol and there's kind of two ways of thinking about this but the key idea in the in the sort of the execution phase is that you have this sequence of transactions and everybody knows and agrees on what the sequence is because it's recorded on ethereum right now given that sequence of transactions there's um there's there's something called the state transition function the state transition function is a deterministic function which takes the next transaction and the current state of the chain and produces some changes to the state

of the chain possibly and then also possibly emits a block on the arbitrary chain so that's a fully deterministic function and what that means is the result of it depends only on the current state and the next transaction and of course the current state only depends on the genesis state and all of the transactions in between right so the current state at any time is fully determinable from the sequence of transactions that have been recorded and that's actually really important one of the things that makes this a rollup is that anybody can start with the genesis state of the arbitrary chain and replay all of the transactions just on by themselves without needing to sync to anything and then know what the

current state is but also if you're in real time if you're a node and you're just watching to see which transactions arrive in the sequence you can execute that state transition function yourself without needing to synchronize or get to consensus with anybody and you can know what the correct result of executing that sequence of transactions is right and there is a single correct result because the state transition function is fully deterministic so most of the time what nodes do is they watch the sequence and then they execute the state transition function themselves privately and any honest party can do that um by executing the protocol and you could do that using you know software

that we'll give to you for free and you can like look at the source code for and so on so that's how all honest parties can know what the result of executing the chain is and that's sort of the common case of what happens but at this point every honest party in the universe in principle knows what the correct outcome of the chain is except the ethereum chain doesn't know and the reason the ethereum chain doesn't know is it doesn't have enough gas to execute all of the arbitram transactions right the whole point of something like arbitram is to be able to do more work than ethereum can do and sort of you know by definition follows from that that ethereum can't

emulate the false the full execution of the arbitrary chain so we have this other piece we call the roll-up protocol which is how participants in the protocol can can cooperatively convince or prove to the ethereum chain what the result of executing these transaction is in other words like what is the the block header hash of the of of you know the next block of the arbitrary chain so there's a so we have the the settlement protocol which does that so does that sort of make sense there's like two two aspects of this if you're an honest party you can just watch the

sequence and execute everything for yourself and you know what the unique correct answer is but also on the side there's this protocol going on to convince the ethereum chain what the result is and that's necessary for things like bridging or if some party wants to be able to wants to know the result without needing to emulate everything themselves right you can go to the ethereum chain and say look the ethereum chain has confirmed or sort of notarized a particular block header hash for the arbitram chain and so you know that that's good and how do you make sure that the block header hash is included in each ethereum block so i mean basically you have no

control over the miners right or the validator so in principle they could exclude you right so it's not included in every ethereum block it's just included periodically in practice it's every few hours there's a checkpoint of the arbitrary chain will get recorded onto the ethereum chain and so you don't need to get it into every block you just need to sort of get a checkpoint in periodically okay so basically the hard finality is is then not a minute um like the soft finality but a couple of hours until it's included on the main chain so uh but no actually so finality if if if by finality you mean that every

honest party knows and agrees on what the result is then you have that back in the beginning once your transaction is sequenced right because once your transaction has been sequenced then the result of your transaction is is deterministically knowable to everyone that is every honest party knows what the can figure out for themselves what the result of your transaction is and this sort of final recording of the checkpoint on ethereum this is just ethereum finding out what the correct result is which everyone else already knew the the thing is basically if you say you inherit security from ethereum then um then basically you you need to you need to wait until it's been

included um in the main chain ah so there's one there's one more piece that i haven't said yet which i hope will close this loop and that is that this the piece of the protocol that records these checkpoints back onto ethereum this piece is fully trustless what that means is any one honest party can force the correct result to be recorded and so that means that you don't need to rely on anyone else to ensure that your transaction will be recorded back on to the ethereum chain you yourself can force that to happen in fact any any party can force the correct recorded the recording of the correct

result so if you believe that ethereum it will operate securely and if you believe that at least one participant in the arbitrary protocol is honest then you have a guarantee that only the correct the correct result and only the correct result will be recorded on ethereum and so you need there to be just one honest party and that can be you that's assuming the sequencer has uh given the honest has sort of broadcast the honest ordering of transactions well so the sequencer in effect the sequencers the sequencers ordering is well the sequencer's ordering is [Music]

by definition the truth of the order of transactions in other words the sequencer decides the order and then this execution layer determines what is the correct result of executing the transactions in that order the sequencer doesn't doesn't make any claims about the results of executing those transactions it just says um here's a set of transactions you can think of it like a like an ordered mempool if you're thinking in um analogy to ethereum right ethereum has the mempool which is all the transactions that have been submitted but not yet executed right so the arbitrary sequencer produces something that's like an

ordered mempool it's a set of transactions that have been submitted and they're in some order and then what the execution phase of the protocol does is it takes those transactions and runs them or tries to run them in order right so the sequencer has established an order and then the job of the execution and settlement phase is to figure out what is the one correct result of executing those transactions in that order yeah so that makes sense but of course uh you know you said before the sequencer does uh you know sort of uh first in

you know orders it by the or the received and of course that's something uh they could lie about no yes that's right the sequencer can lie about ordering um we believe that a sequencer that does that regularly would get caught but over time you know as we move to a distributed sequencer the idea is you have a set of sequencers and you brought you multicast your transaction to all of them and then each of the sequencers publishes its order which it claims was the order of arrival at it and then there's a kind of so then you have like the published sequence of each of the sequencer

instances and then there's a sort of fair merging algorithm which merges those sequences and it it produces a pr the fair merge algorithm has this property which is which is roughly that if transaction a is ahead of transaction b in a super majority of those sequencers outputs then it will be ahead a will be ahead of b in the the merge so if you believe that uh you know that a super majority of the sequencer instances are honestly doing first come first served then the sort of whole distributed sequencer part of the protocol will produce first come first served

and this will actually in effect solve the mev issue right so basically currently the in in the centralized in the centralized uh sequencer in principle the sequencer could extract everything that would on maintain been known as mev in principle that's put in principle yeah and i mean i'll take your word for it that it currently doesn't but basically if you have that sequency sequencer competition where basically the relative ordering is kind of um uh is uh kind of compared between lots of different sequences that entire can of worms is closed right that's right that's that's exactly right both parts of that a dishonest sequencer

could extract a lot of value presumably by um by reordering or by selling auctioning off position and so on uh it could that we currently run the sequencer and we do not do that but long run the solution is to move to a distributed sequencer um and that way you don't have to trust any one party um it is the case now that the sequence we produce is visible to everyone and so if we cheated blatantly it would be evident um also you know we we the arbitrary team have a real incentive to not make our system terrible in that way um by by cheating our users um but nonetheless right um obviously

distributed sequencer is uh is better and that is where we are headed i'm i'm curious since we brought up the topic of mev which you know i think's definitely become like a huge topic right that like lots of people think about uh this does sound like pretty elegant actually but i'm curious does that actually you know what federica said does that fully remove mev or is there still some degree of mbv there well that's a super that's a super deep question um because it partly depends what you mean by mev right um certainly timing matters and there are circumstances where if

alice can see that the thing happens and get a transaction in in reaction to it faster than bob can that alice will be benefited right and so the ability to react quickly to events more quickly than other people and get a transaction in faster than someone else actually does benefit people and the thing about it a first arrival policy is that you know someone can't get an advantage by being close in network distance to uh to the sequencer of course when you distribute the sequencer if the instances are all over the world you know that becomes a more complicated game so there are issues around ordering the other thing to say about mev is that

there or the idea that of sort of exploiting order for in order to get to make money um there are circumstances where people where like a regular user can benefit from uh either reordering or from selling a position in the order so here's here's a good example suppose that you want to do a trade in an amm like say uniswap or or or an equivalent and your trade is big enough that it would actually move the price in that you know in that automated market um so if the price was sort of at the sort of global market equilibrium price

and your trade would move the price a little way away from that there's an arbitrage opportunity that is available to whoever can get a transaction in immediately behind yours right so if you're the person who's going to do this first trade it sure would be nice so you might say well um great i'll i'll do the first trade and then i'll exploit that arbitrage opportunity myself and make some profit the thing is to exploit the arbitrage opportunity you have to do the opposite of your initial trade so um you know if you wanted to do the initial trade you're not going to do that but there is a profitable opportunity to be right behind you in the sequence and if you could sell that then you would actually you could

actually benefit from it right you the end user and in fact the economics of this get a little complicated but if you do a trade that is big enough to move the market you've suffered a little bit of loss due this to slippage in the terminal in the in the jargon and you can actually regain that by selling the position right behind you in the ordering so there are cases where um like clever ordering or bundling of transactions can be beneficial to users and not just a way to sort of a drain value away from from users um and so personally i'm a believer in opt-in um transaction bundling and i think that's the direction this is

going to go in systems that emphasize fairness that is you as a user can submit your transaction directly to the sequencer and get um you know first in first out um ordering or if you think that there's an if you think that you might benefit from having your transaction bundled with other people's by some party you you trust you could submit your transaction through them send it to them and they you know produce a bundle in and submit it so this gets kind of complicated but the bottom line is that there are circumstances where it's beneficial to users to be able to do bundling of transactions

and if that is purely voluntary a thing that happens for you because you opt into it um i think that's a good thing but the idea that someone is sitting there watching your transactions and like reordering it so that they can steal some um you know some fractional eats from you every time you do a thing um that's really harmful um so yeah so i mean we've been thinking a lot about how can we minimize um mev and how could we make it so that people who want to opt in to transaction ordering can do it and we've been trying to build a kind of ecosystem that allows that to happen but a big part of that is this sort of first in first out or first come first served

approach to sequencing which we think is really important an important part of our model and makes it not completely resistant to meve um but um much more resistant than alternatives i think that's really commendable so i think i mean in this space there's this prevalent narrative that mev is actually good because it secures the network and i think this is a false narrative and i don't i don't understand why more people don't call it out because obviously it's the user who pays for it if if you actually do the analysis of how much is spent on mvv it's it's around one percent of total transaction volume so it's huge it's actually it's it's humongous so basically if you guys were to uh where

to tweak your sequencer uh you could be enormously rich with this but yeah so it's i mean it's it's a huge it's a huge market and i think basically finding finding ways that are provably fair and that kind of trick to that super important i need i feel like i need to do a a mini rant here because i think you're exactly right that this like mev extraction is it's a tax on users but it's a text that's hidden you don't know how much was extracted from you or when um and i think that's not how fees that's not how networks should fund themselves if you're going to fund your network you should do it from fees that

are visible to users so you users know what they're paying so that it's in that wallet pop-up that when you do this transaction this is what you pay for the transaction that it's visible and you know i'm a big believer in that the cost of transactions should be visible they should be fair and they should be related to the cost of operating the network and i think mev is none of those things mov extraction is not visible it's not designed with fairness in mind and there's no reason to believe that it collects the right amount to fund the network right the right amount is enough to actually pay for operating the network but not more i just think mev is a really poor way of funding anything

uh yeah sorry and with apologies for no i'm we're totally on the same page yet this is uh this is exactly my stance so yeah um let's back up a little bit um and talk about the arbitrary nodes though so basically so basically when i have a i have a transaction i will send it to a node who is that node what does it do and how is it incentivized sure the node could be anyone can run a node you can run a node um you know you can just download the software and run it we have um so um i mean the answer of who is the node is it could be anybody um a lot of people will use a service provider i think it's a lot like ethereum you can

run a node yourself or you could use a you know big service provider an inferior alchemy or you know any of the companies in that space it's kind of up to you in terms of how they get paid there's different answers to that um if you run the node yourself you know you're running it for your own reasons and you don't have to pay yourself um if you're using a commercial service that runs nodes then you know they're going to have some kind of business model maybe they have a free tier and you pay if you use it a lot maybe you use a node that's run by an application provider and their business model is they want you to use their application they have some way of making money from their application and they're

going to run a node to make that easier for you um so i mean it's essentially the same answer is on ethereum and there needs to be some reason for a person to run a node and it might just be self-interest or might be part of either it might be part of a business model where they're you know they want people they want to see this activity and happen more and so they want to facilitate it i know we run we the arbitrary team we run uh we run some some nodes node services ourselves but if i run an ethereum node i make money off of it right if yeah if you're mining you do although it's not a great business to be in if you just have a regular computer right you can buy a mining rig and then maybe

the economics of that workout totally but if i mistake her for instance on east 2 yeah you do make some money um and we we don't have an incentive program for nodes um we found that we don't really need it as of yet so the other thing to say is they're different just like in ethereum there are different roles that a node can play it can be a regular node which is mostly servicing user requests keeping track of the state it could be what's called a validator which means that it participates in the protocol the settlement protocol to settle the results of transactions to um to ethereum or it could play a special role like the sequencer

there's only one of those and someday there will be there'll be a limited committee of them someday but most nodes are just are like non-um are like non-staking nodes in ethereum okay and the staking notes what about those so the staking nodes currently um right again anyone can let's see so the protocol allows anyone to run it we currently have a limited list of parties who are doing it um but the um the direction we're going is toward a model where anyone can run a validator and there are some parties who are invited to run a validator and they're

compensated for that with you know some funds that come from from from the user fees from the transaction piece because it's trustless um and anyone can sorry anyone can run a validator um we actually don't know who in general you you don't know and can't know who's running validators and that's actually a feature that you know if you put yourself in the shoes of a person who's thinking of cheating and they're gonna ask they're asking is there a validator who's gonna call me out and uh and take my stake the fact that you can't know who might be running a validator is actually um pretty valuable the sort of submarine

validators are an important aspect of the security model so what happens to the transaction fees that users pay because basically um sending transactions on arbitrary i mean it's it's substantially cheaper than on main net but it's not free it's like on the order of like a dollar per transaction or so yeah so the the the short answer is it goes to pay the costs of operating the chain but let me give you the long answer which explains what those are the biggest cost of operating the chain is recording that sequence of transactions on the ethereum chain it's ethereum gas

right and so um the sequencer uh pays the the biggest the biggest source of cost is the l1 gas that the sequencer has to pay to record uh the the biggest part of the fees that you pay actually go to the sequencer to reimburse it for those costs other fees go to to to to cover other parties costs and so basically that money all goes to pay for the sequencer's costs it goes to um validators and it goes to sort of a core set of nodes um and over time this will over time

we're moving toward more transparency in where those fees go the algorithm for determining the fees is you know we're fully transparent about what that is and we've talked about why the fees are set the way they are but basically the the short the short and the short version of that is the fees part of the fees go to reimbursing the sequencer for l1 gas costs and the rest is l2 gas which goes which is paying for the sort of the core nodes and and and uh and some validators so if you think of like the transaction fees that users pay in arbitram uh are will these kind of be

proportional to you know roughly the ethereum transaction fees that you know like you know some kind of percentage well roughly speaking yes that the component of transaction fees that is covering l1 gas um you know how much you have to pay for the l1 cost of your transaction that is going to depend on what is the l1 base fee right if the l1 base fee goes up then the sequencer has to pay more to record your transaction and you're going to end up or you or other l2 transactions are going to end up paying for that right so because that's the biggest

component in practice when the ethereum gas price base fee goes up the cost of arbitrary transactions goes up as well it lags a little bit for some technical reasons um it takes a little while for the arbitrary mechanism to adjust but fundamentally the arbitrary costs follow the ethereum gas costs and essentially it's the cost of recording data now ethereum is moving toward changing its data model in ways that reduce the cost of the kind of data that roll-ups need and so this so-called this is the the dunk sharding or proto-dunk sharding

stuff that people talk about in ethereum research circles and once that gets deployed on ethereum then um the cost of recording roll up data on ethereum will get much lower we think and therefore that the cost of arbitrary transactions and transactions on other roll-ups too will go down a lot but that's basically right the first approximation most of your transaction fee goes to paying to record your transactions data on the launching you you said earlier that um basically i can force a settlement on l1 as an as a position participant in l2 is there any way i can actually grief the synthesizer

by forcing it to settle much more often than it usually would and thus driving up the fees so if you agree you can post more um checkpoints um as a validator um but that's only going to cost you that's only going to cost you money because as a validator if you're getting paid as a validator you're getting paid per time not paid per per post so that's only going to raise your own costs um and if if the checkpoints that you publish are honest then it doesn't require anyone else to respond on chain

this is the optimistic part of arbitrary is an optimistic rollup and the optimistic part is the idea that if somebody posts a correct checkpoint that um everyone else just does nothing and the system after then there's then there's a challenge window a window of time in which after someone posts a claim about what the checkpoint should be um there's a window of time in which anyone else can object right the person who posted the initial claim is staked on that claim and they they will lose that stake if they're lying but basically there's a window of time in which anyone else can object to it and if no one objects after that window

of time challenge window is passed then the system will accept it and that's obviously the common case because as a validator your incentive is to not post a false checkpoint if you do you're going to lose lose your stake um and so your incentive is to post a correct checkpoint and then everyone else's incentive is to look at that checkpoint say yeah it's correct i'm i'm going to just wait um until for the system to accept it and then the system will accept it that's sort of the common case but if someone posts a false checkpoint then you can come in and say no that's wrong here's the right result and you can stake on that and then there's going to be a challenge protocol that happens between the false staker and

you the honest staker you will win that challenge because an honest party can't always win the challenge protocol that's sort of a guarantee of the protocol and then you'll take half the stake of the loser and the other half gets burned so you as an honest party can post a correct checkpoint you can do that whether or not anyone else posts an incorrect one and if anyone disagrees with you assuming you're behaving honestly you will defeat them and take their stake okay fair enough but how as an honest validator am i incentivized to post a checkpoint do i get extra credit for that or because i i incur the gas fees right

that's right that's right so whoever does that incurs a gas fee and we don't currently have a mechanism to reimburse that gas fee currently we post we are our team post correct checkpoints ourselves and we just eat the cost of doing that um but if we don't then someone else can do it and they can they would have to absorb the cost themselves of posting the checkpoint the checkpoint gets posted every few hours so it's not a large cost it's a it's a you know medium-sized ethereum transaction every few hours the biggest cost of l1 gas cost of the system by far is is the data recording that the sequencer does and it does get reimbursed by fees

we will probably eventually move to a scheme where the system reimburses the gas costs of someone who posts a checkpoint as long as they don't post it too often you started talking about the optimistic part of the roll-up so um kind of putting this into the larger context so we've actually had several other guests on before to talk about roll up so basically we've we've we've spoken with um alec lukowski from uh ck sync and eli ben's son and uh from the optimism we've also had the optimism team on so um i i understand the fundamental difference between um zk roll ups so basically you you post a

fundamental proof and basically that that proof is final you get instant finality it only doesn't work for all kinds of transactions but whatever um and then you have the optimistic rollup so how does how is arbitram designed differently from how optimism works so there's a bunch of differences one of the biggest differences with optimism in particular is that arbitrarum is a arbitrary has a fully working and integrated fraud proof system that is and we've had that since the beginning right so we actually have the fraud proof system

in existence and turned on um and it's integrated with the rest of the system um so that's a pretty significant difference um you know it's not something that we say we're going to integrate in the future in fact we're proud of this we are the only rollups evm compatible roll-up system on ethereum that actually has its security proof mechanism turned on and working this is one of the harder parts of not only just building a fraud proof or correctness proof mechanism but actually getting a complete protocol that includes it is pretty hard to do and that's a reason why a lot of projects either haven't done it or are just

promising for the future but we're you know we're proud of having every version of arbitrary has had fully working and integrated fraud groups i think that's a significant difference you can talk about differences in design for a long time the biggest design difference between arbitram and optimism was that we used interactive fraud proofs and they used a non-interactive fraud proof mechanism that is they had it was an optimistic system but if there was a dispute between parties we would resolve it in different ways but about six months ago maybe a bit more optimism pivoted and started using or said they would use um interactive

fraud proofs which is the arbitrary um i mean i think there's some technical differences between how the system work um we one of them is the first come first served sequencing system which um you know we talked about a bunch before that's a thing that um arbitrary does and optimism has a different approach that involves auctioning off the right to to reorder transactions but probably the system that is closest in design to arbitrary among the ones that are out there is his optimism and of course you know other systems that um the other systems that you mentioned uh use zk uh technology which is a very different type of thing which and there the main difference is between

optimistic and ck is in my mind is cost optimistic systems are much cheaper by orders of magnitude to produce the proof and the reason is that the whole part of the protocol where you generate a very complicated cryptographic proof and you know the zk folks always talk about how cheap it is to verify the proof but producing a zk proof is extremely expensive and an optimistic system you don't have to do that the um even in the worst case the optimistic system the cost of proving is much much lower you could you could do proving on an ordinary machine

for an optimistic system in the case of a dispute but because of the optimistic nature of it if there's not a dispute you don't have to produce a proof at all um and that of course is the common case and it's uh it's vastly cheaper cool thanks that's very helpful i i wanted to kind of come back to the topic that we touched on a little bit before which is sort of the topic of like economics of it so you know we talked about that you know this is fee and most of the fee goes towards paying the l1 gas uh but of course there's also you know l2 you know some some additional fee right that's there and

uh so i'd love to maybe if you could speak a little bit about that and then i'm also curious for example optimism right they they launched the optimism token i'm curious also if you have plans for i don't know arbitrary token or like how do you see sort of the economic system evolve in the longer run sure yeah let me talk about the fees um you know as i said before the biggest component of fees is is l1 cost the there is l2 gas there has to be gas right because you need the economic you need to align incentives for users uh because when a user submits a transaction they are imposing cost on other parties and they're using a resource that's limited namely the throughput of the

chain right so you need to have some kind of gas or charging in order to align those incentives in order to keep users from just spamming the chain with junk transactions right and so arbitrary does that in a way that's pretty similar to ethereum we count gas and we the gas fee is normally low it will go up if the chain is busy is congested that is if if people if the transactions that are arriving are um more than the chain the chain's capacity then uh just like ethereum we have this automatic mechanism that raises the base fee um so that you get um essentially use

the use use that price mechanism to ration the limited limited resource but most of the time um you're running at that sort of the minimum base fee so that's kind of how those fees are charged and you know we believe in a scheme where the fees should correspond to the cost of operating the system um and and that that's where that that should go in terms of a token um you know we have not launched a token we have not felt the need to do it all the growth that we've gotten is has been organic we haven't paid anyone to use the system um you know we haven't done tokenomics stuff to try to get people to use the system we've really focused on building a system that meets the needs of users

and developers the one thing we've said for sure is that we are is that if we do ever introduce a token it's not going to be something that generates friction for users it's not going to be something that every user of the system has to have or use or own we're not going to charge fees in an arbitrary token um we think that you know there's huge advantages both in compatibility and just practically for user experience to have the native token of our chain be eth and to have fees charged beneath um you know we haven't you know we haven't found we haven't seen the need to introduce a token you know we are thinking about

decentralization and how governance could work going forward and what are the options there um but um but yeah it's not um uh it's not uh it's not a decision we've you know we've made to do because right now those ex those fees basically go to like off chain labs and then off chain labs pays like the different parties yeah right well so the sequencer fees get go directly to the sequencers account and then the rest right we we distribute to those who are uh who are involved in running um in running the network yeah over time um you know we're moving toward more transparency about that as we um

uh you know as we line up uh say uh a suite of paid validators and and we're and we're thinking through how to um what's the best way to have our community participate in these this sort of decision making that's definitely the you know the end point that we're aiming for is community participation in this and we need to have there needs to be an economic model that's sustainable that covers the costs and so on but you know we want the community to feel like they um they have a role in uh in talking through these issues and getting to us and getting to an outcome that that meets their needs okay so let's talk about um the larger ecosystem and bridges so

obviously you didn't design arbitrary as a standalone system but it kind of works in conjunction with ethereum and there are also um bridges between arbitram and ethereum to kind of bridge acids also i mean basically there are no native at native assets that live on arbitrarium right so basically everything's bridged i assume ah there are some actually yeah so there are some um there are some assets that were built natively on arbitrary um there's some some applications that are arbitrary native that have chosen to mint their their projects tokens on arbitrary so there are some of those but uh most of the value on arbitrary has been bridged over from ethereum

and how does so basically you guys build and uh and operate bridge how how does that bridge work and how how do you envisage the bridge landscape in the future yeah so we have a we have a basic bridge that can bridge eth and erc20s back and forth um and to bridge from l1 to l2 it's a i think a pretty typical kind of architecture so um you make a call to a contract on l1 so if you're say you're depositing eth um i'll tell the story in terms of each but it works pretty similarly if you're using a token um so uh you make a call to a bridging contract on l1 and you pay those eth to

that l1 contract it will hold those eats it will lock them up and your call to to do that transfer you said what address on the l2 chain you wanted those given to usually your own address right um so when that bridge contract receives those eth it will lock them up and then it will send a trusted message up to l2 which causes the same number of eth to be minted up on the l2 chain by the arbitrary code and then deposit it into the account that you asked it to go into um and so um and then in the reverse direction it's kind of a similar thing there is um you make a call to a trusted um

pre-compile contract on the l2 arbitrary chain saying that you want to transfer each that you own on the arbitrary chain down to some address on l1 and that will cause a trusted message to get sent from the arbitrary code on the arbitrary chain to a contract on l1 which will cause those eth that you deposited back at the beginning of my story to get unlocked and paid out so basically you lock the assets on l1 they get passed up to l2 and get minted up there and then you can do the reverse operation as well and we provide a bridge that does that um one of the things that's important for eth the story is relatively simple for erc20s you need to be a little bit careful to make sure that

people don't that each yes each token address on l1 corresponds to a single token address on the layer 2 chain and so you know we have some functionality that lets people do that but basically we provide a basic bridge and then other people can provide more advanced bridging services on top of that and so we see for example one of the issues with an optimistic roll-up is that withdrawing assets from layer two back to layer one has a delay and that's because of that challenge period that i talked about before in the protocol which in practice is seven days and so if you don't wanna wait seven days for your assets to get from the arbitrary chain back onto ethereum

then there's a number of different fast fastbridge services that you can use that will basically you can give them assets on on the layer 2 chain and they will right away emit those assets back to you on the layer one chain right and so um these third-party bridging services provide a bunch of value that people like but they're kind of built on top of the basic bridge that we provide which is the basic way that assets can be moved back and forth in a way that the service that they're providing is a liquidity intervention service and not a bridging service right not so much bridging yeah but there are also people who build bridges between arbitram and other layer 2 chains or

between arbitrarium and other l1s besides ethereum what we provide in our basic bridge is just a bridge between ethereum and and and the arbitrary chain and then other people can build other things um around it on top of that and there's a lot of value for users in those in those sort of third-party bridgings and liquidity services yeah yeah absolutely so um i i have uh an hour worth of questions about bridges at least unfortunately we don't have an hour so basically i will kind of cut this down to one question so um in in the future um how do you how do you think about different scaling solutions coexisting

do you think that i mean will there be roll up to roll up bridges um i i mean how do you see that working yeah i think there will be so you know there's a huge demand for scaling and we expect a large number of people to come into the space and some um you know web 2 companies and others to come in and bring a lot of demand and as much as you could you know as much as we and everyone and a lot of other teams are doing to try to scale up what you can do on one chain um the demand is going to be more than that and so we're going to see i think multiple chains that are coexisting and some of them will be from the same

technology from the same provider and some maybe different technologies from different providers but anyway there's going to be a need to bridge and so i think we're going to see more sophisticated bridging systems and more sophisticated thinking about bridging i know that in our research team we're thinking a lot about the multi-chain future and how bridging can work and what is the optimal way to do it without sacrificing security and so on i think we're going to see a lot of innovation sort of at the protocol level in designing better bridging protocols and that's going to provide a ton of value because i do think we're headed for a multi-chain a future of multiple chains and not just like a single chain that wins

cool well i mean we've covered a lot about arbitrary right a lot of different aspects i'm curious maybe sort of as a final thing can you talk a little bit about you know what are the biggest things that are left to do you know what what does the arbitrary roadmap look like so we have a few things that are coming up soon um the first one is our nitro upgrade so this is kind of a rewrite of our entire software stack which is which is going to lower costs and increase scalability by a large factor and it's better in a bunch of ways and that's currently on test net but we'll be migrating our arbitrary one our sort

of main chain over on to it is a sort of seamless migration um and that's coming up pretty soon we're not talking dates yet but um but it won't be too long uh after that we're we're we're gonna roll out another technology which we call arbitrarium any trust which is a way if if you're willing to make a mild trust assumption in addition to trusting ethereum in particular if you're willing to trust that two out of end members of a data availability committee are honest then we can provide you with considerably lower cost by

moving the recording of transaction data off of the ethereum chain and onto a sort of replicated committee of data availability servers that's arbitrary any trust and we're going to be rolling that out as well those two things are on our shorter term roadmap after that it's really about driving scalability we've we have a bunch of uh cool things in the pipeline which are going to drive scalability up further on a single chain uh you know we're thinking a lot about cross chain bridging um and we're thinking about um you know ways of supporting a multi-chain world because we think the demand is going to be there um and i think there's going to be a lot

of innovation in that area um that's kind of where we're headed it's mostly about driving scale up and driving costs down you know i'm fundamentally a tech i'm fundamentally a tech person not everyone in our team is you know we to be to be successful in the space you need a lot of different uh a lot of different uh types of skill and uh an activity and but for me it's all about sort of driving the fundamentals of our technology forward um and that's really what i'm you know going to continue to be to be focused on we have some really really interesting things in the pipeline right now we're heads down getting nitro and any trust to delivered and after that i think it's an open field we're going to do a lot and i think we can drive costs

down a lot in scalability up a lot perfect sounds exciting ed um where can people go to find out more about aberdrome uh well you can go to arbitram.io and to get information if you're a developer it's developer.orbitrum.io if you wanted you could look at the block explorer or block explorer if you want to see what's happening on our main chain it's arbitscan.io it's that's like the marriage of arbitrary ether scan it's the ether scans teams big block explorer built by the ether scan team that that that lets you follow arbitrarium you can follow us on twitter at arbitram or off chain labs

um or if you're interested in the nitro technology you can probably just google arbitrary nitro and get a bunch of information about about that including information on how to get on the the test chain that you know that is our roll-up tech of the future and a roll-up check of the near future so yeah that's all available if you're interested in following me i'm ed felton f-e-l-t-e-n on twitter or uh or you know you can find me online fantastic thank you ed it's been an absolute pleasure to have you on um i learned a lot thanks a lot for having me this has been fun thank you so much and thanks so much for our listeners as

well and we look forward to being back next week