2nd Edition · Updated for 2026

A baking guide for people who ship.

Sourdough, finally explained in a language you already speak. Your starter is a long-running process. Proofing is a race condition. The oven is production, and production runs hot.

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v2.0.1 · stable release
Sourdough for Developers
A field manual for shipping bread on a schedule — written for people who already understand systems, and are tired of recipes that say “until it feels right.”
Marta Okonkwo
148 pages
no YAML
The problem

You can debug a distributed system. You cannot make bread.

It’s not a skill gap. It’s a documentation problem. Every sourdough guide was written for people who bake by intuition, and you were trained to distrust intuition.

🕯️

“Until it feels right”

Not a spec. Not a threshold. Not testable. You need numbers, tolerances, and a definition of done — and every recipe refuses to give you one.

⏱️

Twelve-hour feedback loops

You change one variable and find out whether it worked half a day later. That’s the slowest test suite you have ever run, and you can’t parallelize it.

🧫

Nobody explains the state

Your starter is a live culture with a memory of everything you’ve done to it. Every guide treats it as an ingredient. It’s a process, and it has uptime.

What’s inside

Eleven chapters. Zero vibes.

Every step has a target number, a failure mode, and a way to tell whether it worked before you commit six more hours to it.

01Prerequisites & Environment SetupFlour, water, a jar, and a kitchen that holds temperature. That’s the whole dependency tree.p. 9
02Bootstrapping a Starter From NothingFourteen days, day by day, including the three where it looks dead and isn’t.p. 17
03Your Starter Is a Long-Running ProcessUptime, health checks, and what actually happens when you leave it unattended for a month.p. 31
04Feeding Schedules as Cron JobsThree schedules for three lifestyles, and how to migrate between them without a restart.p. 43
05Hydration: The Only Config Value That MattersWhy 70% behaves nothing like 75%, and how to change it without rewriting everything downstream.p. 47
06Proofing Is a Race ConditionTemperature and time are competing for the same resource. Chapter 6 is about who wins.p. 61
07Reading the Crumb: Debugging by Cross-SectionForty annotated photographs. Each one is a stack trace. Learn to read them.p. 78
08Rollback: What to Do at 2 A.M.The dough is over-proofed, you’re tired, and there is still a recoverable path. Usually.p. 94
09Shipping to ProductionYour oven runs hot, lies about its temperature, and has no staging environment. Plan accordingly.p. 103
10Scaling Without Doubling the BugsFour loaves is not 4× one loaf. What scales linearly, what doesn’t, and where it breaks.p. 118
11Appendix A — Error Messages, DecodedDense. Flat. Gummy. Sour in the wrong way. Twenty-three symptoms mapped to root causes.p. 131
Read a page

This is what the whole book sounds like.

No mysticism, no grandmothers, no “you’ll just know.” Targets, tolerances, and what to do when you miss them.

6.2 — Why Your Timer Is Lying to You

Every recipe you’ve read gives bulk fermentation as a duration. Four hours. Five hours. Overnight. This is the single most misleading number in baking, because duration isn’t the input — it’s the output.

The actual input is temperature. Fermentation roughly doubles in speed for every 8°C you add. Your kitchen in July and your kitchen in January are two different runtimes:

# same dough, same starter, same flour
kitchen_temp = 18°C → bulk ≈ 7h 30m
kitchen_temp = 22°C → bulk ≈ 4h 45m
kitchen_temp = 26°C → bulk ≈ 3h 00m
Stop timing. Start measuring. Bulk is done at 50–75% volume increase, full stop. Mark the level on the container with tape at minute zero. The tape is your assertion; the clock is a rough estimate you should be prepared to throw away.
The package

Four files. One download.

Delivered instantly. Yours permanently. Free updates for as long as the book exists.

📕

The book — PDF & EPUB

148 pages, 40 annotated crumb photographs, fully cross-referenced. DRM-free, both formats, one download.

📊

The hydration calculator

A spreadsheet. Enter your flour weight and target hydration, get every other number. Handles starter contribution properly, which most don’t.

🗓️

Timing cheat sheet

One printable page. Bulk fermentation times by kitchen temperature, from 16°C to 28°C. Designed to be taped inside a cupboard door.

🔍

The failure atlas

Twenty-three ways a loaf goes wrong, photographed, with the root cause and the fix for the next attempt. Sorted by symptom, not by cause.

Reviews

From people who have read it.

★★★★★

“Chapter 6 reframed proofing as a race condition and something in my brain finally clicked. I had been treating a temperature problem as a time problem for three years. Three years.”

DR
Devon Reyes
Backend engineer, Lisbon
★★★★★

“I have bought nine sourdough books. This is the only one that told me what number to look for instead of describing a feeling I was supposed to already have.”

PS
Priya Sunderam
SRE, Bangalore
★★★★☆

“The failure atlas alone is worth the money. I matched my loaf to photo 14, found the cause, and fixed it on the next bake. Docking a star because I now bake constantly and own a scale that measures to 0.1g.”

TL
Tomás Lindqvist
Frontend developer, Malmö
M
The author

Marta Okonkwo

Twelve years as a systems engineer, four of them on-call. Then a bakery in Rotterdam, where she spent two years discovering that a production kitchen and a production environment fail in remarkably similar ways.

She wrote this book because she kept explaining fermentation to her former colleagues in terms of retry logic and cache invalidation, and it kept working when nothing else did.

She still bakes on Tuesdays. She still doesn’t own a proofing box.

Get the book

One price. No subscription. No course.

A book, three tools, and a permanent download link.

$49 $29
One-time payment · Launch week pricing ends Sunday
  • Sourdough for Developers — 148 pages, PDF and EPUB
  • The hydration calculator spreadsheet
  • Printable timing cheat sheet
  • The failure atlas — 23 photographed failure modes
  • Free updates for the life of the book
  • DRM-free. Yours to keep, on every device you own.
Buy now — instant download
30-day refund, no questions. Read the whole thing, bake three loaves, and if it hasn’t helped, email me and I’ll refund you. You keep the files.
Questions

Before you buy

Do I need to be a developer to read this?

No, but it helps. The book leans on systems concepts — state, scheduling, race conditions, rollback — as a way of explaining fermentation. If those words mean something to you, the explanations will land faster. If they don’t, everything is still defined in plain language the first time it appears.

Do I need special equipment?

A digital scale and a way to read your kitchen’s temperature. That’s genuinely it. There’s a short section on what’s worth buying later and a much longer one on what isn’t — a proofing box, a banneton set, and a $200 Dutch oven are all on the second list.

I’ve already killed two starters. Is this too late?

Chapter 2 exists specifically for you. Most starters aren’t killed, they’re abandoned on day 4 or 5, during the stall that every new culture goes through and almost no guide warns you about. There’s a day-by-day account of what should be happening, including the days where nothing appears to be.

What format is it, and can I print it?

PDF and EPUB, both included, both DRM-free. The PDF is laid out for A4 and US Letter and prints cleanly in black and white, apart from the crumb photographs, which you’ll want in colour. Print as many copies as you like for your own use.

Is there a course, a community, or a coaching upsell?

No, no, and no. It’s a book with three tools attached. You buy it once, you download it, and I will never email you about a masterclass.

Sourdough/dev
© 2026 Marta Okonkwo. All rights reserved. · This is a demo page created for a tutorial — the book, the author, and the reviews are fictional. No bread was harmed.