Napkin Math #23: Serial & Dumb > Smart & Random
In the past few months, we’ve made a push for blog posts at my company turbopuffer. We’re building a search engine that powers Anthropic, Cursor, Notion,...
Napkin Math #22: turbopuffer, fast search on object storage
A little more than a year ago, I started hacking on a new search engine on object storage, starting with vector search: turbopuffer. Today, we’re a full-...
Napkin Math #21: Index Merges vs Composite Indexes in Postgres and MySQ
While working with Readwise on optimizing their database, I found myself asking the question: How much faster is a composite index compared to letting the...
Napkin Math #20: Scaling Causal's Spreadsheet Engine from Thousands to Billions of Cells: From Maps to Arrays
Earlier this year, I spent a few weeks working with Causal on their core spreadsheet engine. Causal is a spreadsheet built for the 21st century to help...
Napkin Math #19: Metrics For Your Web Application's Dashboards
In the beginning of the year I was helping readwise.io get some of their observability up to snuff. A few weeks later "What should I monitor?" came up on...
Napkin Math #18: Neural Net from Scratch
Happy new year everyone! In this most recent post, we will establish a mental model for how a neural network works by building one from scratch! In a future...
Careful Trading Complexity for Improvement
Whenever you find yourself arguing for improving infrastructure by yanking up complexity, you need to be very careful. Published a new article this morning...
Napkin Problem 16: When To Write a Simulator
My rule for when to write a simulator: Simulate anything that involves more than one probability, probabilities over time, or queues. Anything involving...
Napkin Problem 15: Increase Performance by Fitting In the Initial TCP Slow Start Window
Did you know that if your site’s under ~12kb the first page will load significantly faster? Servers only send a few packets (typically 10) in the initial...
Napkin Problem 14: Using checksums to verify syncing 100M database records
A common problem you've almost certainly faced is to sync two datastores. This problem comes up in numerous shapes and forms: Receiving webhooks and writing...
Napkin Problem 13: Filtering with Inverted Indexes
Database queries are all about filtering. Whether you're finding rows with a particular name, within a price-range, or those created within a time-window....
Napkin Problem 12: Recommendations
Since last, I sat down with Adam and Jerod from The Changelog podcast to discuss Napkin Math! This ended up yielding quite a few new subscribers, welcome...
Napkin Problem 11: Circuit Breakers
You may have heard of a “circuit breaker” in the context of building resilient systems: the art of building reliable systems from unreliable components. But...
Napkin Problem 10: MySQL transactions per second vs fsyncs per second
Napkin friends, from near and far, it’s time for another napkin problem! Since the beginning of this newsletter I've posed problems for you to try to answer....
Napkin Problem 9
Napkin friends, from near and far, it’s time for another napkin problem! As always, consult sirupsen/napkin-math to solve today’s problem, which has all the...
Napkin Problem 8
Napkin friends, from near and far, it’s time for another napkin problem! As always, consult sirupsen/napkin-math to solve today's problem, which has all the...
Napkin Problem 7
Napkin friends, from near and far, it’s time for another napkin problem! As always, consult sirupsen/napkin-math to solve today's problem, which has all the...
Napkin Problem 6
Napkin friends, from near and far, it’s time for napkin problem number 6! As always, consult sirupsen/napkin-math to solve today's problem, which has all the...
Napkin Problem 5
Napkin friends, from near and far, it's time for napkin problem number 5! If you are wondering why you're receiving this email, you likely watched my talk on...
Napkin Problem 4
Napkin friends, from near and far, it's time for napkin problem number four! If you are wondering why you're receiving this email, you likely watched my talk...