MVPs, architected to survive success
Fast to market without decisions that trap you later. Specifically: a tenancy model chosen deliberately at day one, because it’s the one thing that’s genuinely painful to change afterwards.
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CUSTOM SAAS ENGINEERINGSaaS platforms built for customer one hundred, not customer ten.
The MVP that proved your market is rarely the architecture that carries it. We build multi-tenant platforms where onboarding a customer is a configuration change, billing runs itself, and the enterprise checklist stops being a blocker.
Tenant isolation · Automated billing · RBAC · Documented public API
MVPs succeed and then become the constraint.
The rebuild always arrives at the worst possible moment.
The pattern is consistent enough to predict.
You built fast to validate, and it worked. Now onboarding a customer takes an engineer half a day. Billing is a spreadsheet and three manual Stripe actions. Every support question needs a developer with database access, because there’s no admin tooling. And the first serious enterprise prospect has asked for SSO, audit logs and data residency — none of which the original architecture can support without significant rework.
None of this means the MVP was built wrong. It means it was built for a different question. The problem is that the rebuild always arrives at the worst possible moment: when demand is finally real and the roadmap has no room.
The decision that matters is which parts genuinely need rebuilding and which can be extended. That’s what discovery answers, and it’s usually a smaller answer than founders fear.
What we build.
MVP-to-scale rebuilds
Taking a validated product and re-architecting the parts that won’t hold. Usually staged so the live product keeps serving customers throughout.
Multi-tenant architecture
Data isolation between customers, tenant-aware queries, per-tenant configuration, and provisioning that doesn’t require engineering.
Subscription billing
Plans, trials, usage metering, upgrades and downgrades with proration, dunning, failed-payment recovery, invoicing and tax handling. Built on Stripe or your provider of choice, with the state machine handled properly — billing bugs cost revenue and trust simultaneously.
Admin and support tooling
So your support and success teams resolve issues without a developer. The most consistently under-scoped part of a SaaS build, and the one that quietly determines your support cost per customer.
Public APIs and integrations
Documented, versioned, rate-limited APIs with authentication for your customers and integration partners. Webhooks that retry properly.
Four decisions that determine what the product costs to run.
| Decision | We recommend it when |
|---|---|
| Tenancy model | Shared schema with tenant IDs, schema-per-tenant, or database-per-tenant. Each has different cost, isolation and compliance characteristics. Shared schema is cheapest and most common; database-per-tenant is what enterprise and regulated customers eventually ask for. Changing this later is the most expensive migration in SaaS, so we decide it explicitly and document the reasoning. |
| Permissions model | Role-based access designed for the org structures your customers actually have — teams, sub-accounts, custom roles, delegated admin. Retrofitting a second dimension of permissions touches every endpoint you’ve written. |
| Billing state machine | Subscription state is the hardest correctness problem in most SaaS products. Trials, upgrades mid-cycle, proration, failed payments, grace periods, reactivation. We build it as an explicit state machine with tests, not as conditionals accumulated over time. |
| Data model for reporting | Customers will ask for analytics. If the transactional model can’t support aggregate queries without degrading the product, you end up building a second pipeline under time pressure. Planned upfront, this is cheap. |
Each of these is cheap to decide at the start and expensive to revisit. They are the four questions discovery exists to answer.
The checklist that unlocks bigger contracts.
At some point a prospect sends a security questionnaire and the deal stalls on things nobody prioritised. These are the recurring items, and they’re much cheaper built in than retrofitted.
We scope these against your actual sales pipeline rather than building all of them speculatively. If nobody’s asking for data residency, it can wait.
SSO / SAML and directory provisioning
Audit logs — immutable, exportable, covering every state change
Granular permissions and delegated administration
Data residency and regional deployment options
Data export and deletion on request
Uptime commitments with the monitoring to evidence them
Encryption at rest and in transit, with key management
Standards on every platform.
Load profile modelled first
Tenants, users per tenant, transaction volume and data growth at launch and at 10x. Infrastructure follows from that, not from a default.
Tenant isolation tested, not assumed
Automated tests that specifically attempt cross-tenant data access.
Billing covered by tests
Every subscription state transition, because these bugs are found by customers otherwise.
Observability from day one
Logging, error tracking, per-tenant performance metrics, alerting.
CI/CD with staged deployment
You ship without ceremony and roll back without drama.
API documentation as a deliverable
Versioned, published, treated as part of the product.
At handover.
Everything below is a deliverable, not an upsell.
Full source code in your repository
Infrastructure as code, deployed to your cloud accounts
API documentation, published and versioned
Architecture documentation including the tenancy reasoning
Admin tooling your non-technical team can use
Monitoring and alerting configured to your team
Handover session with the engineers who built it
30 days of post-launch defect fixes at no cost
GOOD FIT
- You have a validated MVP that’s becoming hard to operate
- Onboarding a customer currently requires an engineer
- Enterprise prospects are asking for things you can’t yet offer
- You’re building a SaaS product and want the tenancy decision made properly at the start
- You need a dedicated team on a continuing roadmap
PROBABLY NOT A FIT
- You want an MVP built as cheaply as possible to test an idea — a no-code prototype may validate it faster and for less
- There’s no in-house product owner. SaaS is a continuing product, not a project, and it needs someone owning direction
RELATED INDUSTRIES & SERVICES
Questions about SaaS builds.
How much does it cost to build a SaaS platform?+
An MVP with proper multi-tenant foundations typically runs $40,000–$100,000. A rebuild of an existing product depends heavily on how much is salvageable — often less than expected. Fixed figure after discovery.
How long until we can launch?+
Usually 12–20 weeks to a launchable first version including billing and admin tooling. Rebuilds are staged so the existing product keeps running throughout.
Should we rebuild or extend what we have?+
Extend, in most cases. The audit tells us which components can carry the next stage and which can’t. A full rebuild is warranted mainly when the tenancy model or data architecture fundamentally can’t support where you’re going — and we show the reasoning either way.
Which tenancy model should we use?+
Shared schema with tenant IDs suits most B2B SaaS: cheapest to run, simplest to operate. Database-per-tenant becomes worth it for regulated industries or enterprise customers demanding hard isolation. We model both against your target customer profile during discovery.
Can you work as our engineering team long term?+
Yes — dedicated teams are the most common model for SaaS. A ring-fenced team on your roadmap, billed monthly, with the same senior engineers throughout rather than rotating resources.
Do you build the billing, or do we use a service?+
We integrate with Stripe, Paddle or your provider — nobody should build payment processing. What we build is the subscription logic around it: plan changes, proration, trials, dunning and grace periods. That layer is where the correctness problems live.
What about SOC 2 or ISO 27001?+
We build to the technical controls those frameworks require — audit logging, access control, encryption, change management. Certification itself involves auditors and organisational process beyond the codebase. We make sure the architecture doesn’t become the blocker.
How long does it take to onboard your next customer?
If the answer involves an engineer, that’s the constraint on your growth and it compounds with every customer you add. Thirty minutes with an engineer will tell you what removing it involves.