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21Day
Studio

Wedon'tpitch.
Weship.

Product studio for anyone who needs a product, not a slide deck. Founders, ops teams, line-of-business owners, professional firms, company size doesn't change the method.

The cycle
Week 01
D 01 · Scope signed
Week 02
D 12 · v 0.1 testable
Week 03
D 21 · Shipped · code handed over

§ 01Why 21 days

Not too short, not too long

Three weeks is the unit where a product takes shape without drifting.

01

Short enough to stay focused

Three weeks force you to cut everything that isn't essential. No scope creep, no months lost debating secondary features.

02

Long enough to ship a real product

Not a prototype, not a demo. A product in production with authentication, payment, dedicated hosting, monitoring. Your users can touch it on day 22.

03

Matches your decision pace

You don't lose a quarter waiting. You decide Monday, we sign Wednesday, you test the product before the month is over.

04

Fixed price, signed scope

Price set at the quote. No scope creep. If we cannot deliver in 21 days, we take the loss, not you.

§ 02Day by day

30 days end-to-end · friction included

Here's what we actually do.

A call, a quote, a signature, an onboarding, 21 days of building, a launch, a warranty. We also dropped in the two days that bit us on recent projects, so you know what to expect.

Pre-cycleBuildReviewLaunchWarrantyFriction

§ 03The team

Zero middlemen between you and the code

Direct line to the founders. No sales rep, no project manager.

01CMO
Portrait of Loris Gautier

Loris Gautier

Marketing, client relationship, operations. First contact, last contact.

02CEO
Portrait of Maxence Foulon

Maxence Foulon

Product vision, scoping, architecture. Makes sure the shipped version stays useful, clear and maintainable.

03CTO
Portrait of Robin

Robin

Cybersecurity, infrastructure, data protection. He locks down risk on sensitive projects.

043 developers · 1 product designer · 1 SRE
ET

Engineering team

Assigned project by project depending on scope. All Europe-based, on 21Day contracts.

§ 04What they say

Shipped clients · 2026

Founders and operators who saw their product live before the end of the month.

01March 2026
« Three months stuck with a freelance before 21Day. They shipped a working version in three weeks. The quote did not move by a single euro. »
Marc · Founder
SouverainIA
AI assistant · B2B
02April 2026
« We had four spreadsheets and an Access database falling apart. 21Day shipped a single multi-warehouse interface. We save about 15 hours a week on data entry. »
Christian · Founder
Ornauto
Internal app · stock management
03May 2026
« An AI advisor plugged into 500 PrestaShop products, shipped without breaking the existing setup. Cost held to the cent, live on day 22 as promised. »
Élise · E-commerce lead
Canoopea
Pet retail e-commerce

§ 05Our expertise

Five areas, one studio

What we know how to build.Shipped in 21 days.

01

Web development

Custom web apps, SaaS, dashboards. From interface to backend, shipped as one lot.

See expertise
02

AI

Conversational assistants, business agents, generative AI plugged into your data. Your code, no SaaS black box.

See expertise
03

Automation

Business workflows, agents, custom orchestration. Maintainable code that you own, not duct-taped Zapier.

See expertise
04

SaaS

Multi-tenant platforms, billing, user accounts, advanced permissions. B2B-ready to scale from launch day.

See expertise
05

Internal tools

Internal apps for your ops, HR, finance teams. Replaces the 4 spreadsheets and the Access database falling apart.

See expertise

All built to live inside the 21-day, fixed-price, your-code frame

§ 06FAQ

Questions that come up

Five questions. Five straight answers.

01
Do I need a spec document to start?
No. A 30-minute first call is enough to scope the project. We draft the quote and Scope Document from the call, you validate, we start.
02
What happens if you miss the 21-day deadline?
We size the scope to hit it. If the blocker is on us, we flag it on day 7 or 14 and align next steps, partial-refund clauses included. The scope signed at the first call is our guard rail.
03
Do I own the source code?
Yes, from day one. Source code, deployment files and hosting accounts are yours, handed over at delivery. No lock-in on 21Day to evolve the product later.
04
What happens after delivery?
Thirty days of functional warranty, included in the package. After that, your choice: monthly maintenance with 21Day, handover to your in-house team, or nothing if it's running fine.
05
Do you take every project?
No. We say no often. If your need doesn't fit 21 days or we're not the right team (pure e-commerce, video games, hardware), we tell you at the first call and point you elsewhere.
When you're ready

Tell us about your project. Quote within 24 hours.

Q3 2026 · 2 slotsLet's talk →
Let's talk →