Field Guide ships focused, four-week courses on the systems you skim over but should understand. Twelve lessons. Real exercises. Office hours with people who built the thing.
Every Field Guide is exactly four weeks long. The lessons add up. By Friday of week three you can do something on Monday of week one you couldn't have explained in a code review.
-- before · 1.18s SELECT id, total FROM orders WHERE customer_id = 38402 AND status = 'paid' ORDER BY created_at DESC LIMIT 20;
CREATE INDEX orders_cust_status_created ON orders (customer_id, status, created_at DESC);
Every Field Guide ships with fixture databases and a sandboxed runner. Type your SQL, see EXPLAIN ANALYZE rendered, find out whether you actually moved the needle.
Opt into a four-week cohort and you get a live office-hour every Thursday, a private Discord with the instructor, and a shared weekly capstone review. Or stay solo — same lessons, your timetable.
Every code block in a Field Guide lesson can have side notes that point at specific lines. Hover a margin note, the line lights up. Read once, learn once.
-- before: 1.18s on 1.4M rows EXPLAIN ANALYZE SELECT id, total FROM orders WHERE customer_id = 38402 AND status = 'paid' ORDER BY created_at DESC LIMIT 20; Seq Scan on orders (cost=0..38402.18 rows=18) Filter: (customer_id = 38402 AND status = 'paid') Rows Removed by Filter: 1,408,118 Planning Time: 0.18 ms · Execution Time: 1184.42 ms
Type what you actually need to learn. Field Guide returns lessons, exercises, and the specific minute marks in office-hour recordings where it was discussed.
Indexes, MVCC, vacuum, replication — the four things you wish your senior had explained.
Consensus, replication, CAP without the buzzwords. By the end you can read a paper and explain it.
Borrow checker, lifetimes, async. We build a small server and break it on purpose, six times.
From "what is a sum type" to ADTs, GADTs, and HKTs — with TypeScript snippets, not papers.
Profiler, suspense, server components — and how to tell which of them you actually need.
What's actually on the wire when you open google.com — handshake, multiplexing, QUIC, ALPN.
Every plan includes lifetime access to lesson material, the sandbox runner, and the alumni Discord. Refunds within 14 days, no form.
Pick one, own it forever. Solo by default — cohort access is +$49.
Browse the catalog →Everything in the catalog, plus every new guide we ship.
Start the 14-day trial →For engineering managers who want learning to show up in their reports.
Book a 20-min call →I'd been "doing SQL" for nine years and reading EXPLAIN was still a vibe check. After Week 1 I rewrote a query at work, 1.18s → 4.2ms. Paid for the cohort in one afternoon.
The pacing is the whole magic. I bounced off Designing Data-Intensive Applications twice. Four weeks of 3.4 hours got me further than four months of "I'll read it on the weekend".
We put six engineers through the Postgres guide as a team cohort. The shared capstone became our weekly internal lunch-and-learn. Three months later, our P95 query latency is down 42%.
Try Lesson 01 of any guide for free — no email required.