James Lovejoy on detecting and mitigating double-spends (EP.111)
On The Brink with Castle Island
Release Date: 08/10/2020
Justin and Hannah (Asymmetry Finance) on Stablecoins, Yield, & Risk in DeFi (EP.619)
On The Brink with Castle Island
Wyatt sits down with and of In this episode, we cover: The evolution of yield in DeFi Primitives users want Crypto risk assessment Learn more about
info_outline
Weekly Roundup 05/02/25 (OP_RETURN wars, Mastercard and Visa push stables, quantum revisited) (EP.618)
On The Brink with Castle Island
Matt and Nic are back with another week of news and deals. In this episode: Will stablecoins disrupt credit cards? The US Treasury Advisory Committee drops a report on stablecoins Mastercard and Visa launch stablecoin integrations Movement labs has more scandals Are quantum timelines accelerating? The real risk of quantum to Bitcoin Could a quantum break fix Bitcoin’s security budget? Are any Bitcoin purists left? Circle turns down Ripple’s acquisition offer Machinsky is facing a 20-year sentence Arizona passes an SBR bill Cambridge releases a new report on bitcoin mining...
info_outline
Kedian Sun (Level Money) on Stablecoin Expansion in DeFi (EP.617)
On The Brink with Castle Island
Wyatt sits down with , the founder of In this episode: Stablecoin usage in DeFi today Fiat-backed stablecoins vs other "stable" assets Ethereum vs other blockchains for stablecoins
info_outline
Weekly Roundup 04/25/25 (Decoupling, Fed Rescinds guidance, 21 Capital) (EP.616)
On The Brink with Castle Island
Matt and Nic are back for another week of news and deals. In this episode: Is Bitcoin decoupling? The Fed rescinds anti-crypto letters from 2022 and 2023 Upexi raises $100m PIPE to invest in Solana Cantor, Tether, Softbank and Bitfinex inject $3.6b into 21 Capital, a Bitcoin acquisition vehicle Bitcoin ETFs versus bitcoin acquisition companies Trump is hosting a dinner for $TRUMP holders Charles Schwab wants to launch crypto trading Citi thinks stablecoins could reach $3.7T in supply by 2030
info_outline
Weekly Roundup 04/18/25 (Signature Postmortem, Mantra collapse, Powell on stablecoins) (EP.615)
On The Brink with Castle Island
Matt and Nic are back with another week of news and deals. In this episode: We recap Nic’s article on why Signature collapsed Crypto exchange OKX their plans to expand to the US Kraken that US equities are now supported on the exchange MANTRA, a layer 1 network focused on RWAs, saw the price of its native token 90% in a matter of hours Global Payments agreed to Worldpay, a payments processor, for $24 billion from FIS and private equity firm GTCR The US Department of Homeland Security has launched a into Anchorage,...
info_outline
Fred Hsu and Michael Ho (D3) on Creating Efficient Domain Name Markets (EP.614)
On The Brink with Castle Island
Wyatt sits down with Fred Hsu and Michael Ho of to talk domain markets. In this episode: The existing domain name industry and legacy systems An interoperable marketplace for domains New financial promitives around domains and RWAs
info_outline
Yuval Rooz and Eric Saraniecki (Digital Asset) on the Canton Network (EP.613)
On The Brink with Castle Island
Yuval Rooz and Eric Saraniecki, co-founders of Digital Asset join the show. In this episode we discuss: The origins of Digital Asset and the path to starting the firm. Views on privacy in the context of public blockchains. How enterprises and financial institutions are approaching tokenizing assets and leveraging blockchain technology. Examples of how on-chain privacy enables use cases in collateral management and stablecoin payments. The role of the Canton Network public blockchain for enabling institutional use cases. How Canton Network works from a design perspective. To learn...
info_outline
Weekly Roundup 04/11/25 (Tether’s new stablecoin, Signature, dedollarization, DoJ disbands crypto team) (EP.612)
On The Brink with Castle Island
Matt and Nic are back with another week of news and deals. In this episode: Is dedollarization happening? The SEC's Division of Corporate Finance released a "" The US Justice Department has its National Cryptocurrency Enforcement team The SEC releases new guidance on securities offerings in crypto markets FDIC Chair relaxes rules on crypto activities at banks Paul Atkins is confirmed The SEC has approved options trading for spot ETH ETFs Tether is exploring a US stablecoin Janover is doing a Microstrategy for SOL strategy Michelle Bowman is launching a review...
info_outline
Wyatt Lonergan and Juan Lopez (Vaneck Ventures) on Stablecoin Adoption and The Institutionalization of Crypto (EP.611)
On The Brink with Castle Island
and of join the show to talk stablecoins and institutionalization. In this episode, we cover: The landscape of stablecoin growth and activity A world with many stablecoins vs few stablecoins Winning/losing companies in the new stablecoin era Impact on the longer tail of altcoins
info_outline
Hoolie Tejwani (Coinbase) on The Evolution of Coinbase Ventures (EP.610)
On The Brink with Castle Island
, the head of Coinbase Ventures joins the show. In this episode we discuss: The history and rationale behind the launch of Coinbase Ventures. The evolution of the crypto venture category. Areas of focus for Coinbase Ventures. Stablecoins, Crypto/AI and consumer startup category. The regulatory landscape in the United States. Operation Chokepoint 2.0 and the impact on startups. The rise of the Coinbase Mafia. To learn more visit
info_outlineJames Lovejoy, recent MEng MIT grad and former graduate researcher at the MIT Digital Currency Initiative, joins the show to talk about his masters thesis and associated project focusing on detecting double-spends in proof of work cryptocurrencies. Previously, little data was collected in a systematic way to detect double-spends and reorganizations across many cryptocurrencies. James' project sheds light on previously unknown security properties of PoW. In this episode:
- How James came to work on Vertcoin
- Why James thinks ASIC resistance is valuable
- James' blockchain monitoring project and why it matters
- Why reorgs are challenging to detect
- Why investigating the economic damage of reorgs is difficult
- How James noticed a 51% attack in progress on Vertcoin and intervened to save Bittrex money – and how this can be replicated
- Why understanding Nicehash is critical to detecting and dealing with 51% attacks
- James' critiques of dominant theoretical models of PoW security
- How James found reorgs and counterattacks happening on BTG in real time
- Why exchange processes like KYC might actually help protect blockchains from reorgs
- How permissionless trading and leverage makes certain blockchains more vulnerable to attacks
- Rules of thumb for confirmation requirements for exchanges
- The issue with calling coins "Nicehash-able" – and why it's likely a lowball
- How exchanges can proactively mitigate the risk of 51% attacks and what they should be targeting
- How BTG developers finally defeated deep reorgs
- Whether James is confident in the long-term prospects of PoW
- Whether James still believes in GPU mining
Content referenced in this episode
- James Lovejoy, An Empirical Analysis of Chain Reorganizations and Double-Spend Attacks on Proof-of-Work Cryptocurrencies
- Raphael Auer, Beyond the doomsday economics of “proof-of work” in cryptocurrencies
- Eric Budish, The Economic Limits of Bitcoin and the Blockchain
- Hasu, Prestwich, and Curtis, A model for Bitcoin's security and the declining block subsidy
- Carlsten, Kalodner, Narayanan, Weinberg, On the Instability of Bitcoin Without the Block Reward
- Moroz, Aronoff, Narula, Parkes, Double-Spend Counterattacks: Threat of Retaliation in Proof-of-Work Systems
- Judmayer et al, Pay-To-Win: Cheap, Crowdfundable, Cross-chain Incentive Manipulation Attacks on Cryptocurrencies
- Liao and Katz, Incentivizing Blockchain Forks via Whale Transactions
- James Lovejoy and David Vorick, ASICs and cryptocurrencies: benefits and drawbacks [debate]
- Nic Carter, It's the settlement assurances, stupid [blog]
- Elaine Ou, Cryptocurrency Deals can Always be Erased, for a Price [article]