SaaS Development · Paris & France

Transform your SaaS vision into a product that scales

You have the idea, the market, maybe the first customers. But building a SaaS that handles load, secures data and evolves without technical debt is a different skill set. We architect and develop your product so it grows with your ambition.

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The challenge

Why so many SaaS projects fail technically

80% of SaaS projects accumulate critical technical debt within the first 18 months. Architecture mistakes at the start cost exponentially more later:

  1. 01 Monolithic architecture that cannot handle scaling
  2. 02 Multi-tenancy absent or poorly implemented: data mixed between customers
  3. 03 No CI/CD: every deployment is a risk, releases are rare and stressful
  4. 04 Makeshift billing: manual subscription management, no reliable revenue metrics
  5. 05 Insufficient security: no SSO, no audit logs, GDPR non-compliant
  6. 06 Degraded performance with the first real users (> 100 active accounts)
  7. 07 Infrastructure costs exploding without correlation to customer count
  8. 08 Technical team overwhelmed by maintenance instead of building features

Solution comparison

Which stack for your SaaS?

We choose the most suitable stack for your context: business complexity, performance constraints, target team profile, and scaling strategy.

Next.js + Vercel

Strengths
  • Full-stack React with native SSR/SSG/ISR
  • Zero-config deployment on Vercel, PR previews
  • Edge Functions for global performance
  • Rich ecosystem: Auth.js, Prisma, tRPC
Limitations
  • Strong coupling with the Vercel ecosystem for certain features
  • Vercel costs that increase quickly at scale (bandwidth, functions)
  • Server Components complex to master
  • Vendor lock-in on edge/middleware features
Ideal for: B2B/B2C SaaS with strong front-end component, time-to-market priority

Remix / React Router 7

Strengths
  • Web standards first: native progressive enhancement
  • Optimized data loading (nested routes, parallel loaders)
  • Deployable everywhere (Node, Deno, Cloudflare Workers)
  • Simplified form handling and mutations
Limitations
  • Younger ecosystem than Next.js, fewer third-party resources
  • Smaller community, more targeted hiring
  • Fewer turnkey hosting solutions
  • Non-trivial migration from Next.js
Ideal for: SaaS with heavy user interaction, complex forms, multi-cloud

NestJS + React/Vue

Strengths
  • Enterprise-grade backend architecture (DDD, CQRS, microservices)
  • Full-stack TypeScript, end-to-end typing
  • Clear front/back separation, specialized teams
  • Proven scalability on distributed architectures
Limitations
  • Two projects to maintain (front + back), more coordination
  • Heavier initial setup than a full-stack framework
  • Requires solid backend expertise (enterprise patterns)
  • More complex deployment (2 services minimum)
Ideal for: Enterprise SaaS with complex business logic, advanced multi-tenant, API-first

Supabase + React/Next.js

Strengths
  • Complete Backend-as-a-Service (auth, DB, storage, realtime)
  • Native PostgreSQL with Row Level Security
  • Drastically reduced development time
  • Open-source, self-hostable, no absolute vendor lock-in
Limitations
  • Complex business logic difficult to implement client-side
  • Limits on advanced backend workflows (jobs, queues)
  • Limited horizontal scaling on free plan
  • Less control over underlying infrastructure
Ideal for: Rapid MVP, early-stage startups, SaaS with standard business logic
No technology dogma. We recommend the solution best suited to your context, constraints and ambitions. Every choice is documented and justified.

Our methodology

How we deliver

Architects with twenty years behind them, and a delivery process instrumented by AI: scoping, code review, quality and security tooled at every phase. Each step produces concrete deliverables, and we stay through the run.

01
2 to 4 weeks

Product Discovery & Scoping

Understand the market, validate positioning, define MVP scope and target architecture. We don't code before having a clear vision.
Deliverables
  • Product scoping workshops (value proposition, personas, jobs-to-be-done)
  • Feature mapping and MoSCoW prioritization
  • MVP definition: minimum scope to validate market fit
  • Target technical architecture (multi-tenant, API, data model)
  • Documented and justified technology stack choice
  • Pricing model and monetization strategy
  • Budget estimate and macro planning
  • Risk matrix and mitigation plan
02
3 to 4 weeks

Architecture & Foundations

Lay the SaaS technical foundations: multi-tenancy, authentication, billing, CI/CD. Decisions made here determine the ability to scale.
Deliverables
  • Multi-tenant architecture (data isolation, per-tenant configuration)
  • Authentication and authorization system (SSO, RBAC, SAML/OIDC)
  • API architecture (REST/GraphQL, versioning, rate limiting)
  • Billing and subscription management integration (Stripe)
  • Complete CI/CD pipeline with automatic quality gates
  • Infrastructure as Code (Terraform/Pulumi) and environments
  • Design system and base UI components
  • Architecture documentation and ADR (Architecture Decision Records)
03
2 to 4 months

MVP Build

Build the MVP in iterative sprints with regular demos. Each sprint delivers testable value. The goal: a product usable by real customers.
Deliverables
  • Iterative development (2-week sprints, regular demos)
  • Optimized user onboarding (time-to-value < 5 minutes)
  • Dashboard and core product features
  • Payment integration and subscription management
  • Automated tests (unit, integration, e2e, coverage > 80%)
  • Monitoring and observability from the MVP
  • Beta testing with first users
  • Iterations based on user feedback
04
2 to 4 months

Scale-up & Growth

Prepare the product for growth: performance, multi-region, advanced features, third-party integrations. Move from MVP to scalable product.
Deliverables
  • Performance optimization and response time (P95 < 200ms)
  • Multi-region architecture if needed (EU, US, APAC)
  • Documented public API for third-party integrations
  • Webhooks and event system for the ecosystem
  • Enterprise features (SSO, audit logs, custom branding)
  • Self-service administration and team management
  • Product analytics and usage tracking (feature adoption)
  • Migration program for beta customers
05
Ongoing

Operations & Continuous Improvement

Operate the product in production with enterprise reliability. Continuously optimize the product, performance and costs.
Deliverables
  • 99.9%+ SLA with 24/7 monitoring and alerting
  • FinOps: continuous infrastructure cost optimization
  • Product roadmap driven by usage data
  • A/B testing and continuous experimentation
  • Security: regular pentests, SOC 2 / GDPR compliance
  • Incident management and structured post-mortems
  • Auto-scaling and capacity planning
  • Knowledge transfer and operational documentation

Business value

What you concretely gain

Expected results

MVP in 3 to 4 months, not 12

Architecture that scales from 10 to 10,000 customers

CI/CD and quality from day 1

  1. 01

    MVP in 3 to 4 months, not 12

    Precise scope, adapted architecture, iterative sprints. Your product is in the hands of real users within months, not a year.

  2. 02

    Architecture that scales from 10 to 10,000 customers

    Multi-tenant from day 1, autoscaling, data isolation. Your architecture grows with your business without major refactoring.

  3. 03

    CI/CD and quality from day 1

    Automated tests, continuous deployment, quality gates. No silently accumulated technical debt while you search for product-market fit.

  4. 04

    Integrated billing and subscriptions

    Stripe, plans, upgrades, invoices, revenue metrics. Monetization is built into the foundations, not bolted on afterwards.

  5. 05

    Enterprise-grade security

    SSO/SAML, RBAC, encryption, audit logs, GDPR/SOC 2 compliance. Your enterprise customers sign with confidence.

  6. 06

    Transfer and autonomy

    Clean code, complete documentation, team training. You take back control when you are ready.

Frequently asked questions

Your questions, our answers

01 How much does SaaS development cost?
A functional MVP with authentication, billing and core features ranges from 80K to 200K EUR depending on complexity. The discovery phase (2-4 weeks) refines the estimate with a precise scope. We always provide a complete TCO including infrastructure and operating costs.
02 Should we start with an MVP or build the full version?
Always the MVP. 70% of initially planned features are never used. We start with the core that validates product-market fit, then enrich through iterations based on user feedback. It's faster, cheaper, and the final product is better.
03 How do you handle multi-tenancy?
We design isolation from the architecture stage: shared schema with tenant ID (most common), schema per tenant (more isolated), or database per tenant (maximum isolation). The choice depends on your security, performance and compliance requirements. PostgreSQL Row Level Security is often the best compromise.
04 What happens after the MVP launch?
We support the growth phase: product iterations based on usage data, performance optimization, adding enterprise features (SSO, audit logs), and preparing for scaling. The goal is to progressively make you autonomous while maintaining a safety net.
05 Can you take over a struggling existing SaaS?
Yes. We first conduct an audit of the existing system (architecture, technical debt, performance, costs) to provide an objective diagnosis. Then we propose a remediation plan: progressive refactoring, migration if necessary, stabilization and optimization. We avoid big-bang rewrites when possible.
06 How do you handle GDPR and SOC 2 compliance?
Compliance is built in from the design phase: data encryption, consent management, right to erasure, audit logs, retention policy. For SOC 2, we implement the required technical controls (access, monitoring, backup, incident response) and document procedures.

Ready to build your SaaS on solid foundations?

Thirty minutes with an architect - the person who will scope your project, and ship it. We analyze your project, your current or desired stack, and give you an initial direction - no commitment.

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