In this AMA, we had the pleasure of interviewing Dean Tribble. Dean is the CEO of Agoric, and had a vast journey in tech by being involved in various software projects and startups since the 80s. He has been pursuing a vision of large-scale networked computer systems and that led him to smart contracts.
This Slogging thread by Sara Pinto, Dean Tribble, Dimitar Bochvarovski, Pawan Sharma, MĂłnica Freitas and Limarc Ambalina occurred in slogging's official #amas channel, and has been edited for readability.
Hey @channel, please join me in welcoming our next AMA guest, Dean Tribble, the CEO of http://agoric.com. Agoric is an open-source development company launching an interoperable Proof-of-Stake chain and economy.
Please feel free to ask Dean anything about:
Please feel free to ask Dean anything about:
- JavaScript smart contracts for better composability
- Scaling web3 through the 10M+ JavaScript developers across the globe
- Reducing common smart contracts vulnerabilities
- Building an economy in the decentralized finance (DeFi) industry
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Dean Tribble
Hello! Thank you for having me!
Hey Dean Tribble, it's great to have you here with us. Can we start off with you telling us a bit about your background?
Dean Tribble
I had my first computer job when I was 15, my first startup (funded by the founder of Atari, Nolan Bushnell) when I was 17. So Iâve been doing software and startups since the 80s. Much of it has been in building large scale distributed systems.
Dean Tribble
I have been pursuing a vision of large scale networked computer systems for literally decades. I worked at Xerox PARC (with a few of my colleagues here at Agoric) on early secure distributed programming languages and operating systems. Modern-day promises in JavaScript and RUST descend from that work. I then went and worked on hypertext (before the web) at Xanadu. Somewhere in there in 1989 I worked on the first production smart contract (yes, 5 years before Vitalik was born đ.
Dean Tribble
Since then Iâve worked on lots of large scale systems from early brokerage information systems in Java to my previous gig of a multibillion dollar payment instrument. Usually itâs about bringing new tech to market to enable mo stranger to cooperate more successfully!
Dean Tribble
That is what got me into smart contracts in the first place: âsoftware enforcing the terms of a contract-like arrangement between multiple partiesâ just enables so much more cooperation in the world. All the businesses from eBay and PayPal to AirBNB and Lyft are that kind of business.
Dean Tribble
Those all require a trusted intermediary, and as we know they arenât always trustworthy đ. But then along came blockchain that enables independent computers in different jurisdictions to run the same software and verify each others work, and suddenly you can run smart contract businesses without the trusted intermediary. Thatâs what got me into building smart contract infrastructure for next generation of blockchains. And here we are đ
Dean Tribble
That makes me realize I skipped Sun and Microsoft in there.
Dean Tribble
At Sun Labs in the 90s, we had a project to build a smart contract platform. Thatâs a big part of the early design work that led to elements of Agoricâs JavaScript smart contract platform.
Dean Tribble
At Microsoft, I was an architect on the Midori (research) operating system, a research operating system using the same aysnc message/ocap/promise based architecture approach that we now use in the Agoric vm/kernel.
Dimitar Bochvarovski
What a career đ
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Dimitar Bochvarovski
Why JavaScript? I mean, me personally am a Web Developer and use JS in my day to day life, and is the language that I won't change for anything else, but there is a lot of discussion about the issues that come with JS, such as dynamic types, and the ease of making mistakes with memory management...
Dimitar Bochvarovski
And I am a big fan of Kyle Simpson, to mention. He has interesting courses for object capabilities in js
Dean Tribble
I love that question because it has both unsurprising and surprising answers.
Dean Tribble
The unsurprising answer is in the ââŠis the language that I wonât change for anything elseâŠâ. 13.9M developers! I want to see more cooperation in the world, and smart contracts are an incredibly powerful tool for helping that happen. For that to matter though, itâs got to be available to most of the programmers in the world. Itâs not much help if, to get a smart contract built, you have to go pray to the priesthood of 10k expensive Solidity developers. Itâs easier to find a good lawyer and do it the old-fashioned way! So we set out to meet devs where they are at and empower them to build smart contracts.
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Dean Tribble
The surprising answer is that JavaScript is more securable than most other programming languages, due in large measure to the contributions of our, Chief Scientist, Mark Miller. Heâs has been driving the needed elements into JavaScript from our earlier secure language work since the beginning. His 2015 paper at financial cryptography on âCapability-based Financial Instrumentsâ showed examples in the E programming language that you can now write in JavaScript on Agoric.
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Dean Tribble
The reason JS is more securable is also partly an accident of history: the JS language was standardized in ECMA, whereas the browser host environment for it was standardized in W3C. That corresponds to a user-mode/system-mode separation that is required for secure operating systems. You have never seen a design boundary as well defended as committees defend their turf đ. So the only way that a JS program/module/whatever gets authority to anything in the system is if itâs put into the global object used for evaluation. In the browser, that global includes
documentfsprocessfreezeDean Tribble
thatâs the âhardened JavaScriptâ. Itâs open-source, available for web2 and web3 at https://github.com/endojs/endo, and runs in any standard JS environment. Itâs the backbone of MetaMaskâs next gen wallet, used in Salesforceâs AppExchange, and of course used for our smart contract platform.
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Dean Tribble, thatâs incredible! You had quite the journey. I have to ask, in the name of the not-so-tech-savvy folks, could you elaborate on smart contracts on the blockchain? And what do you mean by composability?
Dean Tribble
As for what a smart contract is: âsoftware enforcing the terms of a contract-like arrangement between multiple partiesâ. That it! Hence eBay and PayPal and Lyft and StubHub all are largely smart contract business deployed by a âtrusted intermediaryâ. So smart contracts were $1T+ market cap *before* blockchain. We rely on the intermediaries to faithfully execute their software, and most transactions go through without any human involvement by the hosting company.
Dean Tribble
Such businesses took off much faster once there were good libraries and platforms to rapidly compose new businesses without coding everything from scratch (e.g., shopify, stripe, etc. all provided components that developers could reuse).
Dimitar Bochvarovski
Why was it so hard to came up with a "code that can be executed on the blockchain", which is what the smart contract is in general (correct me if I am wrong), and we needed to wait for Ethereum to come with this solution?
Dean Tribble
But my favorite component model example is in the UI space (I worked on UIs as an intern in the Smalltalk group at PARC after all). Before React/vue/etc., experts could build some pretty cool stuff in JavaScript. BUT itâs a nightmare to debug fancy apps written in raw HTML/JS (I still recall my last round of trying to debug why the tax rate of some purchase page wasnât changing when the user changed their zip code). React provides a component framework for user interface components that completely addresses many of the hard problems in building fancy UIs, and more, enables components built by multiple parties to work together extremely well.
Dean Tribble
The result is that shortly after React came out, new developers can build fancier, safer, more responsive, more helpful applications than experts could the year before React. Thatâs what a component framework gets you.
Dean Tribble
Our goal is a framework that provides the same kind of support, but for smart contracts that handle digital assets, pricing, etc. (instead of ouse clicks and rendering). In platforms like Ethereum, there are security hazards that are frankly too high-risk for cryptoexperts, let alone application programmers just trying to solve their business problem. Our framework is designed to protect developers from those hazards.
Dean Tribble
So a smart contract is not âcode that can be executed on a blockchainâ, since there was $1T+ of value in smart contracts before blockchains!
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Dean Tribble
Bitcoin is itself a smart contract; itâs software thatâs enforcing rules for transfer of BTC. Itâs the first smart contract that didnât need a trusted intermediary.
Dean Tribble
Eth brought support for running other peopleâs software. There were a couple of requirements for that. The gold standard of blockchain is
multiple computers in different jurisdictions and different administrative domains all coming to consensus about data, choices, and computation.
Iâll unpack that, and then talk about why itâs important đ.
Pawan Sharma
Hey Dean Tribble Could you please explain a bit about offer safety in Agoric and does it refunds the original asset plus the transaction fee or just the original asset ?
Dean Tribble
multiple computers in different jurisdictions and different administrative domains all coming to consensus
Means that no human, organization, or government can unilaterally change the systems behavior. They would have to simultaneously compromise a majority of machines (which are controlled by other parties) to compromise the integrity of computation.
about data, choices, and computation.
Data: âDean has $100 in his accountâ
Choices: âDean tried to withdraw his offer before the auction closed. Did he win the auction and spend his money or did he get his money back?â
Computation: âthe auction ran and determined that Dean would be the winnerâ
Choices: âDean tried to withdraw his offer before the auction closed. Did he win the auction and spend his money or did he get his money back?â
Computation: âthe auction ran and determined that Dean would be the winnerâ
Dean Tribble
The novel hard technical part is âall coming to consensusâ. If you know all the computers (you donât) and you can rely on them all to not cheat (you canât), then we know how to count votes and make sure itâs a majority. The area of Byzantine Fault Tolerance covers handling the âwhat if they cheatâ. The most brilliant insight in BitCoin was how to address consensus when you donât know all the participating computers.
Dean Tribble
Finally, for those computer to all check that they agree, they have to actually agree! So the same program run with the same arguments multiple times in multiple places have to produce the same answers (this is called âdeterministicâ). That turns out to be hard! If they can see the clock, they can behave differently. If they can see any memory address, they can behave differently. If they can see when garbage collection happens,âŠyou get the idea.
Dean Tribble
So Solidity has a lot of issues, and is very low-level, but it does execute deterministically. Our hardened JavaScript lets you run JavaScript deterministically! That will make all this accessible to a lot more developers
Dean Tribble
Pawan Sharma asks about âoffer safetyâ in Agoric. Thatâs one of the critical properties of the smart contract framework. Familiar safety properties are things like memory safety and type safety, where they just completely eliminate some large class of bugs. They donât solve everything but they can take 80% of bugs off the table.
Dean Tribble
Offer safety is a safety property at the economic level.
First the setting: In existing blockchains smart contract systems, you execute transactions by sending money to a ârandom numberâ (an account address) and hoping something good happens. People have sent (and lost) assets to âaddressesâ that werenât real accounts, that were wrong accounts, to contracts that then had failures, etc. This model is both error-prone and a horrible user interaction. I want to send money to my friend John, not to 0x234ag3453.
First the setting: In existing blockchains smart contract systems, you execute transactions by sending money to a ârandom numberâ (an account address) and hoping something good happens. People have sent (and lost) assets to âaddressesâ that werenât real accounts, that were wrong accounts, to contracts that then had failures, etc. This model is both error-prone and a horrible user interaction. I want to send money to my friend John, not to 0x234ag3453.
Dean Tribble
Real business involves quid pro quo: âI will give you $X if you give me concert ticket Yâ. We support that directly. So in our API, clients invoke smart contracts by making
offerwantgiveexitDean Tribble
So whatâs offer safety look like for an auction?
- seller makes an offer to the auction smart contract in which they want at least $40 and they will give a concert ticket X
- each bidder makes an offer in which they want the concert ticket X, and give an amount corresponding to their bid.
Zoe holds all the assets, and notified the contract of each offer. When the auction closes, the auction contract atomically
No misbehavior, bug, etc. on the part of the auction contract can enable it to take money from the bidders that are not getting the concert ticket.
reallocatesNo misbehavior, bug, etc. on the part of the auction contract can enable it to take money from the bidders that are not getting the concert ticket.
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Dean Tribble
That means that the clients of the auction are MUCH safer. They donât need to read the auction code to know that they get their desired ticket or their money back.
Dean Tribble
Also the creator of the auction contract is happy too: many of the hazards in Solidity are around handling money that you are not supposed to hold onto. There have been literally $1B+ lost/stolen due to sloppy handling of returning money from contracts. With Zoe and offer safety, you donât need to write a single line of code in the contract to deal with that safely.
Dean Tribble
A related property is âpayout livenessâ: remember each off has an
exitwantDean Tribble, thank you so much for your detailed answer! What about the smart contracts vulnerabilities? How can they be reduced?
Pawan Sharma
Dean Tribble Great explanation !!
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Dean Tribble
For ways to reduce smart contract vulnerabilities, we discussed
- offer safety
- payout liveness
Additional critical ways:
- async coupling to prevent reentrancy
- component reuse to avoid reimplementing everything
Dean Tribble
In Ethereum and other chains (most recently PolyNetwork), billions in losses have come from âre-entrancyâ. Thatâs where if there are 2 components (or contracts) A plans to call B and then do something X, but B calls back into a (re-enters A) before it can get to X. For example, A is an auction, an B requests a refund from bid. B says âsend me my refundâ, and so A looks it up, and sends the refund to B, and then records that it has given a refund to B. BUT when B is sent the refund, instead of replying âthanksâ, it immediately send the âsend me a refundâ message to A again. Since A has not yet recorded that B has received its refund, it goes ahead and sends the refund again. And again, B reacts to that with âsend me a refundâ. The A service never gets to the point of recording that B has received its refund, so B just does this until it has drained Aâs account. It sounds absurb when said like this, but this was exactly the bug in 2017 that got folks wondering whether the tech behind Agoric could help blockchain. And one $660M exploit last year was the same basic problem. Itâs because the architecture of Eth allows, supports, and even requires reentrancy.
Dean Tribble
The Agoric model is fundamentally asynchronous, meaning that when A sends a message to B, it doesnât sit there waiting for B to do something. It moves on and finishes recording what it needs to record. It means that trivial example arenât quite as trivial, but it also means that non-trivial examples (like DeFi) arenât fraught with security hazards.
Hey Dean Tribble! Great to have you with us! What would you say are the main challenges when it comes to building an economy in DeFi?
Oh, I see. Thanks for explaining, Dean Tribble. Reentrancy can cause a lot of trouble. Is there any way to know when we are dealing with a reentrancy system?
Dean Tribble
re rentrancy; itâs part of the system architecture, and so cannot be papered over with different languages or helper libraries. A system in which calls between contracts or contract components are call-return (A calls B and waits for the answer) are almost always reentrant. If while A is calling B (âhey get me my refundâ), someone else can call into A, then itâs likely reentrant. The architectures that arenât either use asynchronous messaging (like agoric) or just have limited semantics (like e.g., Kadena).
Dean Tribble
re challenges in building an economy in DeFi
- building a solid platform of course. We are finishing that now.
- bootstrapping the liquidity. Markets work because thereâs money of some form providing grease for the gears. Believers need to bring that âgreaseâ up front so that itâs easy for users to trade with each other rather than struggling with the system.
- navigating regulatory issues. ânuff said.
Dean Tribble, what about scaling web3 through JavaScrip developers? What do you mean by that? Is something Agoric is working on?
Dean Tribble
Itâs at the heart of what we are working on. Lots of folks talk about scaling transaction speed or blocksize or latency. But the hardest thing to scale is the developer base. To reach a significantly larger community of developers, we cannot expect that they will drop their current languages and tools and work on yet another programming language. We must âmeet them where they are atâ.
Dean Tribble
So with agoric:
- developer in the most popular programming language on the planet
- using the most popular development environments and tools
- with programming models that they are familiar with (event loops with promises, react-style components, etc.)
Dean Tribble
The specifics matter (e.g., JavaScript with async execution and such) but it also matters that the priority is enabling developers that just want to get something done. Our platform should grow like JS and Node did: from teh ground up because it enables programmers to get stuff done! :)
Dean Tribble
My goal is that âif you can build a web2 application for the cloud, you can build a web3 application for agoricâ. Itâs early, so we arenât there yet, but we will be.
Hi Dean Tribble thanks for joining us! My question is: why open source? What benefits and cons does this model have and how do the pros outweigh the cons?
Dean Tribble
Lots of reasons for open source.
Personal motivation: Iâve had the opportunity to work on some amazing projects. The problem is that some of the most amazing didnât ship, and so that part of my life had some fun, interesting, but ultimately much less valuable time spent. Much of what we are doing is finally building an open source version of really useful tech that weâve built in multiple incarnations, but havenât been able to easily carry forward into new projects.
Personal motivation: Iâve had the opportunity to work on some amazing projects. The problem is that some of the most amazing didnât ship, and so that part of my life had some fun, interesting, but ultimately much less valuable time spent. Much of what we are doing is finally building an open source version of really useful tech that weâve built in multiple incarnations, but havenât been able to easily carry forward into new projects.
Dean Tribble
Cultural motivation: JavaScript is a largely open-source world. And we want lots of reusable components. Historically, that kind of reuse flourishes best in an open source environment: devs know that other devs are goign to the same tech stack for components, so thatâs where they will build and contribute their components.
Dean Tribble
And finally: the core value prop of blockchain is high integrity via decentralization: smart contracts are executed on multiple computers run by independent operators in different jurisdictions. If they are all running the same, closed-source software, then we would get essentially no decentralization. The implementors are a single source of failure. And really it needs to grow into community-owned code. Thatonly really works with open-source.
That's a wrap! Thank you so much for being here answering our questions, Dean Tribble. Do you have any final thoughts or is there anything you'd like to promote?
Dean Tribble
We will be launching our âmainnet1â to provide a community-backed stable token for the interchain environment. Come participate with the community in http://agoric.com/discord and sign up for the newsletter and http://agoric.com/newsletter ! And if you are web2 developer, checkout endojs. Thanks for having me!
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Dean Tribble
And of course our Agoric announcement channels,
Telegram (https://t.me/agoric_ann) and Twitter (https://twitter.com/agoric).
Telegram (https://t.me/agoric_ann) and Twitter (https://twitter.com/agoric).
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