Skip to content
21Day
21Day · Product studio
Now bookingQ3 2026 · 2 slots

21 days / fixed price / your code

We ship your productin 21 days.

Web, mobile, software, automation, infra.We ship. No slide deck.

Book a callSee shipped products

01

21 days, shipped

02

Fixed price, no scope creep

03

Your code, day 1

04

Functional warranty, 30 d

The numbers

No empty promises.Just measurable units.

01
0
Project shipped
Since 2026
02
0
Days per project
No slip
03
0%
Code ownership
Yours, day one
04
0 d
Functional warranty
Bug fixes included
21
Why 21Day exists

Builtwhereinfra,product
andsecuritymeet.

Systems and network discipline, turned into a product method: scope clearly, ship fast, keep the base clean.

Origin

Three responsibilities. One short cycle.

At EKOD in Le Mans, Maxence, Loris and Robin aligned on one simple idea: product, cadence, security.

  • Product
  • Cadence
  • Security
Version

Clarify

Less

Fog

More

Version

Lessfog.Moreversion.

We do not turn a vague intent into an infinite backlog. We choose a useful, visible, shippable version.

Frame

Limit

Less

Scope

More

Frame

Lessscope.Moreframe.

Every addition has to replace something else. The cycle protects momentum from the meeting that makes everything bigger.

Ownership

Transfer

Less

Dependency

More

Ownership

Lessdependency.Moreownership.

At handoff, you get the code, access, decisions and a base another team can pick up.

Fiveguardrails.
Onecyclethatdoesnotdrift.

01Before D 01

Signed scope

We write what is in, what is out, and who validates. The cycle starts when that frame is accepted.

Guardrail

Scope document

Guardrail · 01 / 05Next →
02D 03 → 07

Visible version early

The first screens and flows arrive quickly. You do not discover the product at the last minute.

Guardrail

Testable URL

Guardrail · 02 / 05Next →
03All cycle

Short decisions

When a decision blocks, we lay out the options and choose. No validation tunnel.

Guardrail

24h decision

Guardrail · 03 / 05Next →
04D 14 → 18

Real-world review

Review happens on a running product, with data, roles, payments or integrations when the scope requires them.

Guardrail

Live product

Guardrail · 04 / 05Next →
05D 21

Clean handoff

We hand over code, access, decision notes and deployment instructions. The warranty starts after that.

Guardrail

Code + access

Guardrail · 05 / 05Locked
Held cycle

Less drift.
More product.

The process is not here to fill time. It protects delivery when details start pulling in every direction.

Cycle guardrails
01 · AI assistant · B2B
Project 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
Projet 003
Overview
Routes
Counterparties
Reconcile
Webhooks
Volume · 24h
€ 482 k
+12%
Success rate
98.4%
+0.6 pt
Orchestrations
1,204
stable
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
Project 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.
Your account is live. Patients can book starting tomorrow.
Open dashboard
4 min · 4 steps · Day 21
10
Signature lines

Tenlineswe
repeatwithoutapologising.

We don't pitch. We deliver.

Repeated · varied · never abused

02

Three weeks. Flat price. Premium quality.

03

Founders are the captains. We're the co-pilots.

04

Ship with us. Then keep flying.

05

We say no often. It's how we stay good.

06

Your code is yours from day one.

07

The product speaks. Not the slides.

08

Custom software, made considered.

09

Modern tools. Human craft.

10

Quiet conviction. Durable work.

When you're ready
Now bookingQ3 2026 · 2 slots

Threeweeks.
Notthreequarters.

Six fields, two minutes, a direct slot. Fixed-price quote within 24 hours. Scope locked at the call. No follow-up emails, unless you want them.

01
Form
2 min online
02
Quote
Within 24 h, flat fee
03
Kickoff
Day +2 after signing
Let's talk See the work first→
Let's talk →