SaaS & Product Development · UK & US

Ship the product. Then survive its success.

We design, build and scale multi-tenant SaaS platforms — from a first release that proves the market to an architecture that holds up under enterprise buyers, real security reviews and ten times the load.

10–12 wks to first usable release2 wks sprint cadence100% of the IP is yours
UK company — Registered in England & WalesDelivery — United Kingdom & United StatesResponse — Within 1 working hour
An idea No code yet An MVP Starting to strain Customers Asking for more FITSOL Product Engine SHAPEARCHITECTBUILDSCALE In production Shipping fortnightly Enterprise-ready SSO, RBAC, audit Handed over Docs, tests, runbook YOUR REPOS, YOUR CLOUD, YOUR IP WHAT YOU BRING An idea · An MVP · Customers waiting FITSOL Product Engine SHAPEARCHITECTBUILDSCALE Shipped · Enterprise-ready · Handed over YOUR REPOS, YOUR CLOUD, YOUR IP
Fortnightly
working software, every time
Yours
code, cloud and roadmap

Book a free architecture review

45 minutes with a principal engineer. Bring an idea, a codebase or a stalled roadmap — you will leave with a straight answer about what to build and what to fix first.

The problem

The four ways SaaS builds go wrong

We are usually called in at the point where one of these has already happened. All four are cheaper to design against at the start than to fix at scale.

An MVP that became the architecture

It got you to first revenue, then every new feature took twice as long as the last, and now a rewrite is on the table.

The first enterprise deal you cannot close

They want SSO, audit logs, role-based permissions, data residency and a completed security questionnaire. You have none of it.

Cloud costs rising faster than revenue

Nobody designed for cost, so the infrastructure bill grows with usage in a way the pricing model never anticipated.

An agency that owned your product

Undocumented code, no handover, no tests, and a dependency you cannot leave without starting again.

What you achieve

What you end up owning, not just renting

The outcomes we design towards from the first sprint, agreed in the architecture review before anyone writes code.

10–12 wks

To first usable release

In real customers' hands, on foundations that will carry version five rather than a prototype you throw away.

2 wks

Sprint cadence

Working software demoed every fortnight, so you always know exactly what your money bought.

100%

Your intellectual property

Code, designs, infrastructure and documentation in your repositories and your cloud account from the first commit.

1

Principal engineer

The same senior technical owner on your account from the first call through to handover.

Where most builds end up
Every new feature takes longer than the last and nobody knows why
The first enterprise prospect asks for SSO and audit logs, and the deal stalls
Cloud spend grows faster than revenue because cost was never designed for
There are no tests, so nobody dares refactor anything
The code lives in an agency's account and leaving means starting again
With FITSOL product engineering
Multi-tenancy, billing and permissions designed before the first sprint
SSO, RBAC, audit trails and a security evidence pack ready when asked
Infrastructure cost per tenant modelled against your pricing, not discovered
Automated tests and CI/CD, so shipping stays fast at version five
Your repositories, your cloud account, your IP — from the first commit
Scope it yourself

How long would your first release actually take?

Move the sliders to match what you have in mind. A rough shape only — the architecture review gives you a real sequence and a real timeline.

Core features in v1
External integrations
User roles & permission tiers
Enterprise requirements
Indicative first release
from kick-off to customers using it
Two-week sprints
Suggested squad size
Get a real timeline for your product

Assumes a dedicated cross-functional squad and a decision-maker available weekly. Scope discipline moves this number more than team size does.

Capability

What we build

Product engineering with commercial instincts — because architecture decisions are pricing, sales and hiring decisions in disguise.

MVP and first release

The smallest thing that proves the market, built on foundations that will carry version five — not a prototype you have to throw away.

Multi-tenant SaaS platforms

Tenant isolation, subscription billing, usage metering, provisioning, admin tooling and the operational plumbing every SaaS eventually needs.

Enterprise readiness

SSO and SCIM, role-based access control, audit trails, data residency, penetration testing and the evidence pack that gets you through security review.

Modernisation & rescue

Legacy monoliths untangled, technical debt paid down in a sequence that keeps shipping features, stalled builds diagnosed and restarted.

AI-native product features

Copilots, semantic search, generative workflows and agents designed into your product as differentiators, with unit economics that work at scale.

Dedicated product teams

A cross-functional squad — product, design, engineering, QA and DevOps — working to your roadmap and inside your process.

How it fits together

The blueprint we build to

Every engagement is designed as a system, not a feature. This is the shape of it — reviewed and agreed with you before a line of code is written.

What you bring
A market insight or an idea
An existing codebase or MVP
Customers asking for more
FITSOL Product Engineering
01
ShapeDiscovery, user research, scope cut to what actually proves the thesis
02
ArchitectMulti-tenancy, data model, security and cost designed before code is written
03
Build & shipTwo-week sprints, CI/CD, automated tests, demoable software every fortnight
04
Scale & hardenPerformance, observability, enterprise controls and cost optimisation
What you end up owning
A product in your customers' hands
Documented code in your repository
A team that can take it on
· Your IP, your cloud account, your repositories· Fixed-scope or dedicated-team models· Handover documentation as a contractual deliverable
How we deliver

A clear route from idea to impact

Every engagement follows the same five stages, so you always know where you are, what comes next and what you are paying for. No mystery, no drift.

01

Discover

User research, competitive reality check, and scope cut hard to what genuinely proves the thesis.

Weeks 1–2
02

Define

Roadmap, success measures and the commercial constraints — pricing, tenancy, compliance — written down.

Week 2
03

Design

Multi-tenancy, data model, security, cost per tenant and the user experience, decided before code.

Weeks 2–4
04

Deliver

Two-week sprints with working software demoed every fortnight, CI/CD and tests from sprint one.

Weeks 4–12
05

Optimise

Performance, observability, enterprise controls, cost tuning — and a clean handover to your team.

Week 12 onward
Start with stage one — book an architecture review
Technology

Built on the platforms you already license

We pick boring, well-supported technology for the parts that must last, and we are happy to explain any choice to your CTO, your investors or your next engineering hire.

Front end

  • React
  • Next.js
  • TypeScript
  • Vue
  • React Native
  • Tailwind CSS
  • Design systems

Back end

  • Node.js
  • Python
  • FastAPI
  • .NET
  • Go
  • Java
  • GraphQL & REST

Data

  • PostgreSQL
  • SQL Server
  • MongoDB
  • Redis
  • Elasticsearch
  • pgvector
  • Event streaming

Cloud & DevOps

  • Azure
  • AWS
  • Google Cloud
  • Kubernetes
  • Docker
  • Terraform
  • GitHub Actions

SaaS foundations

  • Multi-tenancy patterns
  • Stripe billing
  • Usage metering
  • Auth0 & Entra ID
  • SSO & SCIM
  • Feature flags

AI in product

  • Anthropic Claude
  • OpenAI
  • Vector search
  • RAG pipelines
  • Agent tooling
  • Evaluation harnesses
Why FITSOL

Why founders and product leaders work with us

Most agencies optimise for the build. We optimise for what you own when the build ends — because that is what decides whether version five ships in a fortnight or a quarter. Six reasons that matters:

Speak to a consultant 0161 883 7701

FITSOL is the trading name of Future IT Consultancy Limited, registered in England & Wales (No. 07644491), headquartered in Manchester and delivering across the UK and United States.

Before you call

The questions we are always asked

Who owns the code and the IP?
You do, from the first commit. We work in your repositories and your cloud accounts wherever possible, and full ownership of code, designs and documentation transfers to you under contract. There is no scenario in which your product is hostage to our relationship.
Fixed price or a dedicated team?
Fixed scope and price suits a well-defined first build. A dedicated team works better once you have customers and a moving roadmap, because scope changes weekly and fixed-price contracts turn every change into a negotiation. We will tell you which fits your situation.
Can you take over an existing codebase?
Yes, and we do it often. We start with a technical audit — code quality, architecture, security, test coverage and the real cost of the debt — then give you an honest recommendation on repairing versus rebuilding, including when rebuilding is the wrong answer.
How do you handle enterprise security requirements?
By designing for them early. SSO and SCIM, role-based access control, audit logging, encryption, tenant isolation and data residency, plus support through penetration testing and the security questionnaires that arrive with every large deal.
Do we need AI in our product?
Only where it genuinely improves the job your users are doing. We have the capability in-house and we will happily build it — but we will also tell you when a well-designed feature beats a language model, which is more often than the market currently admits.
What happens when the engagement ends?
You get documented code, infrastructure as code, runbooks, architecture decision records and a structured handover to your own team or a new partner. Many clients keep us on a light support retainer; none are obliged to.
Can you work with our existing developers?
Yes. We regularly embed alongside in-house teams, taking a workstream, providing specialist skills, or setting up the engineering practices — CI/CD, testing, code review — that let a growing team keep shipping.
Next step

Get a straight answer about what to build

Bring an idea, a codebase or a roadmap that has stalled. Forty-five minutes with a principal engineer and you will know what to build first, what it will cost you in time, and which decisions you cannot afford to defer.

Or call us directly 0161 883 7701
UK company — Registered in England & WalesDelivery — United Kingdom & United StatesResponse — Within 1 working hour

Book an architecture review

Tell us where you are starting from and we will bring the right principal engineer.

Goes straight to our team and we reply within one working hour during UK and US business hours. No newsletter, no list, no sharing your details.

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