An Interview with the Architect — Kleros CTO Clément Lesaege.

Stuart James
May 30, 2018 · 6 min read
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Clément at work.

Clément Lesaege is the CTO at Kleros which is a blockchain dispute resolution layer providing fast, secure and affordable arbitration for virtually everything. To find out more about Kleros check out our site here. Questions were asked by Kleros Community Manager Stuart.

When you’re not thinking about Game Theoretical problems what do you like to do in your spare time?

I play Magic the Gathering at a competitive level. It’s a card game where you are a wizard which can invoke creatures and cast spells in order to try to kill your opponent. It’s really interesting as it is quite complex, involves strategy and bluff. But you could argue that it does not really answer the question as game theory can be applied to Magic (see this and this article) but in practice, we have a limited time to think during a match so we can’t use techniques that complex.

I also like to travel and often stay a bit more in countries I visit for work.

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You’re a member of the Pirate Party and ran for office twice in legislative elections, when did you become a supporter and why?

I became a Pirate Party member in 2012. The main reasons are:

  1. Reform of state governance to make it more democratic (referendum of popular initiative, local democracy, open gov, participative democracy).

I was introduced to cryptocurrencies by the writings of pirate party members Rick Falkvinge and Ploum. There is a lot of similarity between pirate and crypto philosophy: decentralization, open source (or with Ethereum even open execution). But state and blockchains are different, mostly because you can fork a blockchain, but forking a state is harder (even if some seasteading projects like Blue Frontiers could allow “forking” states). So for a state we have to focus on democratic governance while with blockchain systems, the choice can be an individual one (which system to use, which fork to follow).

You’re one of leading smart contract developers in the scene, tell me a little about your beginnings with tech, first computers, hacks, gaming etc?

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Turtle graphics.

The first “programs” I made were simple drawing programs with turtle graphics when I was in primary school. I learned HTML and PHP on my own when I was in high school (don’t ask me to do any web development though as the way people do it now is quite different and my skills would be obsolete…).

I like gaming and spent quite some time on it when I was younger (especially strategy games, I think the best game I played was Sid Meier’s Alpha Centauri). Now, I don’t have that much time for gaming anymore, but still play video games once in a while (the last game I played was Rim World).

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The legendary Alpha Centauri — 1999

I was not particularly drawn to hacking (I was in the only group on my network security class to do the course project on how to protect from malicious intruders instead of hacking) but it changed with the DAO hack.

When it happened, I learned more about solidity and about how the hack took place. I had a plan to withdraw my ETH from the DAO and even to hack back the hackers. But finally, the fork decision came and I just got my ETH back.

One of the fundamental pillars of Kleros is the Schelling point and the game theoretical background. Tell us more where this interest came from and when you realised this could function to incentivize jurors to vote honestly?

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The classic Game Theory conundrum.

A lot of Kleros was inspired by the Truthcoin paper which was a project to create a prediction market blockchain including a decentralized Oracle. We built on top of that to allow arbitrary dispute resolution and to make it scale.

As for game theory, I was introduced to it during political discussions. Applying this to blockchain projects seems quite exciting as politics is mostly about how to change the rules to the rules you support, while in blockchain projects, we are in a brand new world and we can focus on determining what would be the best “rules of the game” instead of having to fight for “our rules”.

When did you start in crypto?

I started in 2013 with Bitcoin. I bought a few and sold some on LocalBitcoin while teaching the buyers how to use it. I also played a bit with multi-signature wallets for a student project.

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Tell us some stories about your crypto experience?

I had some coins on mtgox but withdrew them before the exchange blocked withdrawals. I have been lucky. Since then I never kept a significant amount of coins on custodian exchanges. Before that there were also stories of DDOS attacks which provoked some BTC price drop (see the song Blame it on Mtgox).

The DAO hack was also quite a story as explained in a previous question. I had put ⅓ of my ETH in the DAO. Even without a fork I had some open split proposal and would have been able to use it to withdraw my ETH from the DAO but I still consider myself lucky.

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The DAO in pictures.

In the crypto space we never get bored, but after all those years I’ve learnt to be quite relaxed about price swings as those happen all the time and should not be too much of a distraction.

Did you mine?

No, I never mined, mostly to avoid having a permanent noise at my place, but I’ll stake when Proof Of Stake will be there.

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What’s the biggest challenge for crypto to become mainstream?

Crypto is becoming mainstream. The challenge now is to have crypto become mainstream for good. We now see a lot of projects, made for banking industry (like ripple) or governments (like the petro) trying to surf on the hype of cryptocurrencies for goals quite different to the ideals of decentralization most people involved in crypto had in the beginning. Cryptocurrencies are not the “revolution”, decentralized ledger technology is.

So the challenge is to get mainstream adoption without losing what crypto was initially made for (i.e. decentralized permissionless systems).

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Clement and trippy Pyramids: Writing Smart Contracts since 2686BC.

You can view a number of Clements recent presentations at Devcon Cancun, ETHLDN and ETHCC by clicking the respective links. Find out more about Kleros and our IICO (Interactive Coin Offering) here.

Learn More

Join the community chat on Telegram.

Visit our website.

Follow us on Twitter.

Join our Slack for developer conversations.

Contribute on Github.

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