The Playbook's 2026 Beach Reads

Time flies when you’re on the beach.

The sun on your skin, the salty breeze, the pulse of the tide. You sense the sand on your feet as you turn the pages, and your reading slowly pulls you somewhere else.

The day is no longer measured in hours, but in chapters, until you finally realize that the light has softened and the day has quietly carried on, without you.

Last year, I put together a reading list for the summer, and enough of you replied back to tell me it made their flight, their train ride, or their time on the hammock a bit nicer.

Hence, I’m making this a tradition.

This week, I’m putting together a list of the most engaging articles from The Payments Engineer Playbook for you to read, peruse, and immerse into. I’ve organized them into topics so that going from one article to the next is seamless. And I’ve included at least a free article in each of those sections, in case you’re not a paid subscriber yet.

Enough intro, let’s, today more than ever, dive in.

What is a ledger anyway?

Most engineers building ledgers have a lot of confidence on their abilities and their expertise. They understand that a ledger is just another software system, and are sure that they can build one using the patterns they’ve learned elsewhere just fine.

And then something breaks spectacularly.

If this has happened to you, or you don’t want that to happen, this articles will put you on the right track to gain the specialized knowledge you need to build ledgers.

• You Don’t Know What a Ledger Is For (free)

• Why Ledgers Must Be Immutable

• How to Explain Accounting to Payments Engineers

• The Only Accounting You Need to Know to Build a Ledger

How to be Double-Entry safe

Double-entry safety is the core invariant in a ledger system. You know, the “sum of debits equals some of credits” that keeps the books balanced and all the funds accounted for.

The problem many engineers encounter is that they approach this invariant from their own perspective about money. These intuitions are very cash-centric, and therefore they fail to understand that accounting isn’t really about moving money, but about transferring ownership.

These articles will help you build the correct intuitions about how to think about double-entry safety, debug problems faster and build ledger systems better.

• Source-Destination Pairs Need Imaginary Accounts to Work

• Ledger Transactions Don’t Have to Be Atomic

• Virtual Bank Accounts Are Virtually Inexhaustible (free)

• No Such Thing As a Currency of Reference

The noise around stablecoins

I’ve been skeptical about the adoption of cryptocurrency as a widespread alternative to money.

Stablecoins are interesting precisely because they’re the closest any crypto can get to fiat money. The point isn’t to become an alternative to fiat, but to bring what’s good about crypto to the real economy.

In other words: what’s disruptive about stablecoins is that they aren’t disruptive.

In the following articles, I’ve articulated a vision for this interesting new technology and its potential for new products and payment methods.

• Stablecoins for Skeptics (free)

• TigerBeetle’s Stablecoin Mistake

• Forget Agents: Here’s What’s Great About x402

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Hope you have a wonderful summer. I’ll see you next week.