/services · 04 / 10

Multi-tenant, from the first commit.

Zero to one: multi-tenant scalable maintainable products, built as if they were ours. No MVPs that become legacy by week eight.

Engagement12 — 32 weeks
Team2 — 3 senior
OutputSaaS in production
DisciplineXP + Extreme Contracts
01 · The premise

An MVP isn't an excuse to write badly. It's a promise to scale when the market asks.

We build SaaS products as if we had to maintain them for five years — because that's often what the founder wants. Multi-tenancy, billing, auth, admin panel, observability: we don't wait for "phase 2", we design them from the first commit with the right discipline for the current stage.

The approach is pure Extreme Programming: pair-engineering on critical pieces, TDD on anything that isn't throwaway UI, CI/CD from the first push, refactor as continuous practice, simple design revisited every sprint.

We apply Extreme Contracts externally (toward the client, toward users) and internally (toward the future maintainer). Every API has explicit versioning, every schema has reversible migrations, every feature has a kill-switch.

02 · What we deliver

What we deliver.

/01

Multi-tenant architecture

Isolation strategy, tenant routing, billing-aware, observability per tenant. No shortcuts that you pay for at Series A.

/02

Auth, billing, admin

Auth with SSO/OAuth, billing with a serious provider (Stripe, Lago), admin panel for support and operations. The real foundations.

/03

CI/CD pipeline

Tests in CI, automatic deploy to staging, feature-flagged deploy to production. One-click rollback.

/04

Observability stack

Structured logging, distributed tracing, metrics, error tracking. Operational unknowns are debt that will mature.

/05

Operator runbook

Living documentation for the team operating the SaaS. Onboarding a new engineer in under a day.

03 · XP in action

How we operate.

XP / Pair Programming
Pair on critical pieces, always.

Billing, auth, multi-tenancy: zero solo coding. Two pairs of eyes before merge.

XP / TDD
Tests as executable spec.

Tests describe how the system behaves. Documentation is written with the client, not for the client.

XP / Small Releases
Daily deploys, never weekly.

The smaller the deploy, the less risky it is. The more frequent the deploy, the more you learn about real risks.

Contracts / API Versioning
No silent breaking changes.

Explicit versioning. Deprecation cycles. Migration guides. Future-you thanks you.

04 · The contract

Pre-conditions, post-conditions, invariants.

Every engagement has explicit pre-conditions, measurable post-conditions, and invariants we never violate. You know what we need at the start, what comes out at the end, and what we don't negotiate in the middle.

Pre-conditions / what we need from you
  • Founder or technical stakeholder available for weekly sync.
  • Design system or basic visual lines (even just rough Figma).
  • Explicit decision on stack constraints (e.g., preferred cloud, region, compliance constraints).
  • Agreed infrastructure budget — cloud isn't free and needs sizing.
Post-conditions / what we guarantee
  • SaaS live, with the first real tenants (not just demos) onboarded and billed.
  • Repository, infrastructure and access owned by the client.
  • Working CI/CD, live observability, written runbook.
  • Formal knowledge transfer: the internal team can take the ball within 30 days.
05 · When it works

Right fit, wrong fit.

YESRight fit if…
  • You're building a B2B SaaS from scratch and want to do it right the first time.
  • You have a live product but technical debt is slowing you down — you want a serious replatform or extension.
  • You have real users incoming and can't afford an MVP that collapses at first load.
  • You want a partner that thinks like a founder, not like a vendor.
NOWrong fit if…
  • You need to validate an idea before building. For that you need other figures, not us.
  • You want a team that executes specs written by others. We only work when we participate in decisions.
  • The timeline is "two weeks until investor demo". We can, but we'd compromise quality — we'd rather wait.
/start

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