The past few days delivered some big-name announcements that have triggered a renewed focus on blockchain architecture. One came from stablecoin issuer Circle, which used the occasion of its Q2 results to reveal plans to launch a blockchain called Arc, powered by Circle’s stablecoin USDC. According to Circle’s statement, Arc will be “designed from the ground up to serve the next era of stablecoin-native applications,” such as tokenization, foreign exchange swaps and derivatives, to name just a few. Another was more inadvertent — payments giant Stripe posted an open role for a product marketer for its Tempo blockchain, still in stealth. A journalist noticed, wrote about it and although the ad was swiftly taken down, Stripe has not denied the report. The posting described Tempo as a “high-performance, payments-focused blockchain” being developed in conjunction with VC firm Paradigm. Its head will reportedly be Paradigm co-founder and managing partner Matt Huang. Both announcements raise an obvious question: Why build a new blockchain from scratch when there are already many to choose from in the market? Assuming that customization is the answer, why not at least work within an existing ecosystem? For instance, ethereum is the largest smart