01Day 00
Brief
Describe your problem in eight minutes. Foundations laid before you finish your coffee.
Step · 01 / 05Next →
21Day · Product studio · v 1
Now bookingQ3 2026 · 2 slots
Twenty-one days.One productin real hands.
A product studio for founders who ship. We don't pitch. We deliver — one cycle at a time, in three weeks.
01 — Cadence
Three weeks is not arbitrary. It is the unit at which momentum compounds and product-market fit becomes legible.
02 — Restraint
A studio earns trust by what it removes. We design the smallest version of the right thing and ship it.
03 — Evidence
Every cycle ends with a working artefact, not a deck. The proof is in the version number.
The numbers
Noemptypromises.Justmeasurableunits.
010
Cycle in flight
Since 2026
020
Days per cycle
No slip
030%
Code ownership
Yours, day one
040 d
Functional warranty
Bug fixes included
01
Concreteoverclever.
"Three weeks. Working app. Real users." Not "we unlock velocity." Language is precise or it is false.
02
Quietconviction,durablework.
No exclamation marks. No "we're excited to announce." We show the work. Trust comes from what is shipped, not what is promised.
03
Timeisourunit.
Days, weeks, sprints, builds. The number is always present. It is the only honest way to talk about a product.
Fivesteps.Threeweeks.
02Day 01
Quote
Fixed-price quote within 24 hours. No surprises. No scope-creep ladders.
Step · 02 / 05Next →
03Days 02 → 14
Build
Focused production. Daily standups. Mid-cycle review on day 14, on a build that runs.
Step · 03 / 05Next →
04Days 15 → 18
Review
You test on a live build. We fix. Unlimited iterations within the locked scope.
Step · 04 / 05Next →
05Day 21
Ship
We deploy, hand over the keys, and stay reachable for thirty days.
Step · 05 / 05Shipped
Day 21 · ShippedOne product.
One product.
In hand.
Three weeks end-to-end. The brand quiets down and the product starts working.
Cycle progress
01 · AI assistant · B2B
Cycle 001 · 2026 · shipped
SouverainIA
A digital exec assistant for French SMB leaders — watches inbox, drafts replies, generates quotes. In production, 10-day trial.
nexus.21day.studio / orchestration
Cycle 003
Overview
Routes
Counterparties
Reconcile
Webhooks
Volume · 24h
€ 482 k
+12%
Success rate
98.4%
+0.6 pt
Orchestrations
1,204
—
Throughput · last 7 days
Hourly
CounterpartyRouteAmountStatus
Maven Healthstripe → sepa€ 8,420settled
Forma Inc.stripe → ach€ 2,160in flight
Atlas Logisticslemonsqueezy€ 14,200settled
02 · Pet retail e-commerce
Cycle 002 · 2026 · in flight
Canoopea
An AI advisor assistant for 500 products, integrated in the PrestaShop catalog. Advises every visitor like a passionate, 24/7.
9:41
Step 02 / 04
Tell us about your practice.
Speciality
General practitioner
Practice type
Solo
Group
Patient volume
0~ 240 / week500+
Continue
9:43
Onboarding complete
Welcome,
Dr. Aronson.
Dr. Aronson.
Your account is live. Patients can book starting tomorrow.
Open dashboard
4 min · 4 steps · Day 21
Signature lines
Tenlineswerepeatwithoutapologising.
Repeated · varied · never abused
- 01We don't pitch. We deliver.
- 02Two weeks. Flat price. Premium quality.
- 03Founders are the captains. We're the co-pilots.
- 04Ship with us. Then keep flying.
- 05We say no often. It's how we stay good.
- 06Your code is yours from day one.
- 07The product speaks. Not the slides.
- 08Custom software, made considered.
- 09Modern tools. Human craft.
- 10Quiet conviction. Durable work.
Whatwesayoutloud.Inwriting.
The principles behind the work, made public. Three pillars: doctrine, case studies, field reports.
When you're ready
Now bookingQ3 2026 · 2 slots
Threeweeks.Notthreequarters.
Brief in eight minutes. Fixed-price quote within 24 hours. Scope locked at brief. No follow-up emails — unless you want them.
01
Brief
8 min online
02
Quote
Within 24 h, flat fee
03
Cycle
21 days, 30-day warranty