Illustration développement SaaS
Custom SaaS development

Custom SaaS development, from idea to a product built to grow

We design and develop your SaaS end to end: multi-tenant architecture, subscription management, dashboards, API. From MVP to a version that handles real load, with no rewrite in between.

Launch my SaaS
AFPG
Artelia
Chambre d'Agriculture Eure-et-Loir
Credit Advisor
Geodeep
Hôpitaux de Strasbourg
Inserm
Solène
Université de Strasbourg
Université Lyon 2
AFPG
Artelia
Chambre d'Agriculture Eure-et-Loir
Credit Advisor
Geodeep
Hôpitaux de Strasbourg
Inserm
Solène
Université de Strasbourg
Université Lyon 2
AFPG
Artelia
Chambre d'Agriculture Eure-et-Loir
Credit Advisor
Geodeep
Hôpitaux de Strasbourg
Inserm
Solène
Université de Strasbourg
Université Lyon 2

Have a SaaS idea?

The SaaS (Software as a Service) model turns your solution into a monthly or annual subscription. No install at the client's end, everything runs in the browser, and updates land at the same time for everyone.

We build the back-office you'd expect from a 2026 SaaS: account creation, organisation management, roles and permissions, recurring Stripe billing, dashboards, API for third-party integrations. No need to stitch ten tools together, we start from a consistent base.

We deliver iteratively: we ship an MVP quickly to test the idea against the market, then grow the product based on real user feedback. More useful than spending six months polishing in the dark.

We start with a free first scoping, then project scoping goes on to frame the MVP scope, figure out which modules add value from v1 and which can wait. Scoping gives you a number you can hold us to, not a figure that doubles mid-project.

Launch my SaaS
Use cases

With custom SaaS development, you control your product, your data and your user experience.

User account

Manage user accounts

Registration, authentication, roles, permissions...

Manage user accounts
API

Communicate via API

with your internal tools or partners.

Communicate via API
Stripe

Integrate Stripe payments and subscriptions

Smooth and automated billing.

Integrate Stripe payments and subscriptions
Clients

Offer a complete client portal

Dynamic dashboards, multi-role access.

Offer a complete client portal

Examples.

Situations we come across often, and the tool we can make of them.

Customer onboarding on a single page

TodaySix documents to email back, a mandate to print and scan, and three weeks of reminders.
TomorrowA link to a page in their name: they upload documents and sign online, you see what is missing.

A customer area with no password

TodayUsername, password, captcha: for a space opened three times a year, customers give up before getting in.
TomorrowA Google button or a link sent by email: they get in with one click and find what is waiting for them.
Commitments.

What we hold to, from the MVP to the version that takes real load.

Tenant isolation

Pool, bridge or silo: the isolation level is settled before the first line of code.

Billing that runs itself

The subscription cycle runs on Stripe, with its customer portal reachable from your app.

A number you can hold us to

Scoping sets a range for your scope, not a figure that doubles mid-project.

Your code, your repository

We push to your repo from day one. No locked layer, no captive licence.

Ready for the auditor

Architecture aligned with your certification target, controls documented for your CISO.

Releases that don't break

The automated test suite is in place from the start, not the day production goes down.

Scaling decided upfront

Auto-scaling and database replication are settled at architecture time, not when traffic spikes.

Readable contracting

Fixed price on scoped phases, then time-and-materials with a monthly day quota.

Projects.

Concrete custom development achievements

+ 150 projects delivered+ 10 years of experience
See all projects
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Identify levers to strengthen farm autonomy

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An extranet to centralize all information and documentary resources

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Offer a mortgage simulation that matches real lending conditions

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Provide tools to master energy consumption

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Carry out genomic sequencing projects

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Identify levers to strengthen farm autonomy

Logo

An extranet to centralize all information and documentary resources

Logo

Offer a mortgage simulation that matches real lending conditions

Logo

Provide tools to master energy consumption

Logo

Carry out genomic sequencing projects

Logo

Identify levers to strengthen farm autonomy

Logo

An extranet to centralize all information and documentary resources

Logo

Offer a mortgage simulation that matches real lending conditions

Logo

Provide tools to master energy consumption

Logo

Carry out genomic sequencing projects

Our approach.

How we build a SaaS that holds up past the MVP stage.

A single instance of the app serves all your clients, with strict data isolation per organisation. We decide together on the level of isolation (logical via a tenant_id, or physical via a dedicated schema) based on your industry: a SaaS in health or finance doesn't face the same constraints as a general productivity tool. The choice happens during the software architecture phase, before the first line of code.

We plug Stripe into the full cycle: multiple plans, trial periods, upgrades/downgrades, expired card handling, payment retries. The Stripe customer portal is directly accessible from your app, which saves you from building a full billing self-service in-house. Stripe webhooks feed your internal dashboards through a dedicated API.

We deploy on AWS, GCP or Vercel depending on context, with auto-scaling on the app layer and a database that can be replicated. In practice, scaling is prepared at architecture time, not the day traffic explodes. We set up a solid automated test suite from the start so deployments don't break production.

The budget depends on the number of business modules, the multi-tenant model, billing and third-party integrations. Upfront scoping lets us break the scope down into priorities using the MoSCoW method so the budget stays tight without dropping the features that carry the value.

For an MVP in production with paying early adopters, expect 3 to 5 months. We ship a first usable version in 4 to 8 weeks so your early users can start paying for it. We then extend the product on the back of their feedback rather than assumptions, which avoids building features that end up in the graveyard.

No-code saves time on early prototypes but hits a ceiling on performance, customisation and vendor independence. A custom-built SaaS costs more upfront, but you own it, the stack fits your business, and infrastructure costs stay linear instead of spiking with your row count. The right call as soon as the product carries a serious share of your revenue.

Benefits.

What you get with a custom-built SaaS.

A custom SaaS means predictable recurring revenue first. It also means a product you fully control — the roadmap, the pricing, the integrations, the terms of service.

Compared to no-code or template-based solutions, a custom SaaS doesn't hit a ceiling on cases the base tool can't handle. When your business has a specific rule, we write it; when a client needs an integration, we add it.

On the technical side, the architecture is built to carry you smoothly from your first ten users to your ten thousandth, without a rewrite midway.

What a custom SaaS gives you, in practice:

An app available 24/7 from any browser

End-to-end recurring billing handled by Stripe

Multi-user management with roles configurable per client

An infrastructure that absorbs growth without rebuilding

Dashboards tracking MRR, churn and LTV over time

An interface that stays usable on mobile and tablet

Frequently asked questions.

What clients ask us most often before launching a SaaS.

The budget depends on the scope: tenant model, integrations, billing, SSO, administration. The initial scoping gives you a range you can hold us to, not a figure that doubles mid-project.

Between 4 and 8 weeks after kick-off for a B2B MVP with authentication, one tenant model, and the main usage scenario. The condition: a clean scoping phase, which rarely takes more than a week.

By isolation requirement and customer profile. Healthcare or finance customers typically require silo (database per tenant). SMB SaaS usually starts in pool (shared database, tenant_id column). Bridge fits regulated industries that need physical separation per region.

Backend: Django, FastAPI, Node.js (NestJS) — chosen by team familiarity and use case. Frontend: Next.js, React, TypeScript. Database: PostgreSQL with row-level security for tenant isolation when relevant. Hosting: AWS, Scaleway, Vercel, or your existing cloud.

You do. Every line. We push to your repository from day one. There's no locked layer, no captive licence. If you decide to bring it all in-house in 18 months, we document, train and walk away.

We deliver an architecture compatible with the certification target, document the controls, and work with your CISO or compliance lead. We don't issue the certificate ourselves.

Fixed price for scoped phases (scoping, MVP, clearly specified modules). Time-and-materials for ongoing evolution post-launch, with a monthly day quota and short sprints.

A process to digitize?

The first scoping is free, with no commitment.

Describe it in a few lines: you get a first reading of the need, the points to decide and a budget range.

Let's talk about your project