Due diligence that stalls
The outsourcing questionnaire comes back half-answered: nobody can say who has production access, where data is processed or what happens on exit.
Fintech software development · UK
Fintech Software Development Company in the UK
We build software for UK fintechs and financial services firms with the delivery habits regulated work needs — audit trails, controlled releases, separated environments — and plain answers when your compliance team assesses us as a supplier.
- Change control and audit trails by default
- Open Banking and KYC via established providers
- You own the code and the cloud accounts
Choosing a fintech supplier
Where software suppliers let regulated firms down.
The code is rarely what fails the review. It is the supplier’s access controls, change history, data handling or exit terms — found out when your compliance team or a partner bank starts asking questions.
What a fintech supplier should give you
- Honest answers about what they can and cannot provide
- Named, logged and reviewed production access
- A reviewed and approved route for every change
- Your ownership of the code, accounts and documentation
Shared logins and forgotten access
Production credentials passed around a chat group, and people who left the project months ago still able to reach live systems.
Releases nobody approved
Changes go live straight from a developer’s machine, with no review, no test record and no named approver when something goes wrong.
Customer data in test
Copies of live customer records in development environments and on laptops — an avoidable UK GDPR problem, and a hard one to explain.
Lock-in by accident
The supplier holds the cloud account, the repository or the only copy of the documentation, so your exit plan exists only on paper.
Advice they are not qualified to give
A supplier tells you a design is “compliant”. That is your compliance function’s call, and a supplier who blurs the line adds risk rather than removing it.
Who it is for
Who we work with in financial services.
The firms differ in size and permissions, but share one need: software delivered in a way their compliance team can oversee.
Launching under a partner’s permissions
Products built on a bank or e-money partner’s platform, where the partner’s technical and security requirements shape the build as much as your own.
Adding products and channels
New customer journeys, integrations and operational tooling for authorised firms that need change delivered under control.
Applications and servicing
Application journeys, decision workflows and customer servicing portals, with every decision and override recorded.
Client portals and reporting
Onboarding, information capture, statements and client reporting for firms whose customers expect clarity.
Modernising without disruption
Legacy tools and spreadsheets replaced step by step, with change control strong enough for internal audit.
Selling into banks
Suppliers whose own customers are regulated — and who need their software, and their delivery, to survive a bank’s vendor review.
How we deliver
Delivery practices that stand up to scrutiny.
Regulated firms do not just need working software; they need to show how it came to be, who approved it and who can touch it. So we make the evidence a by-product of the way we work, rather than a document written the week before an audit.
Every change starts as a ticket, goes through a pull request reviewed by a second engineer, runs automated tests and reaches production only through the deployment pipeline — as a release you approve, with a rollback plan. Development, staging and production are separate environments with separate credentials; live customer data stays in production, and testing uses masked or synthetic data. Access to production is limited to named people, logged, and reviewed with you.
Inside the application, audit trails are part of the data model: who viewed or changed a customer record, who approved a payment or overrode a check, and when. Those records are what let you answer a complaint, an auditor or a partner bank with facts rather than recollection.
- Ticket, review, test and release linked for every change
- Separate environments and credentials, no live data in test
- Named, logged and reviewed production access
- Application audit logs designed with your compliance team
Supplier due diligence
When your compliance team assesses us as a supplier.
If your firm is regulated by the FCA, bringing in a software supplier is a third-party risk decision — and if the software supports one of your important business services, it touches your operational resilience work as well. Your firm stays responsible for the outcome, so your compliance team will want to understand who we are, how we work and how you would leave.
Tell us at the start what your policy requires from a supplier, and we will go through it with you and say plainly what we can provide and what we cannot — before either side spends time on a proposal. Our engineers are based in the UK and India, so expect your DPO to ask who can reach which environment, from where, and how any international transfer of personal data would be covered; those questions need answers before anyone is given access.
Exit planning is the easy part: you own the code, cloud accounts and documentation from day one, so leaving us is a handover, not a negotiation. What we will not do is tell you the arrangement meets your regulatory obligations. That judgement belongs to your compliance function; our job is to give them accurate information to make it.
- Your requirements reviewed before a proposal, not after
- A straight answer on anything we cannot provide
- Code, cloud accounts and documentation owned by you
- Regulatory judgement left with your compliance team
Clear responsibilities
Who does what in a regulated build.
A lot of trouble in fintech projects starts with blurred responsibilities. We agree this split in writing at the start, so nobody assumes someone else has it covered.
Your firm
Holds the permissions, sets policy and risk appetite, decides whether the product meets your regulatory obligations, and approves each release.
Your regulated providers
Banking, e-money, Open Banking, card and identity partners provide the regulated services under their own permissions, through their APIs and terms.
Techsleight
Designs, builds, tests and documents the software — onboarding with KYC and KYB checks, Open Banking and payment integrations, back-office tools — to your requirements, and evidences how it was done.
Fintech solutions we build
Independent testers and auditors
Penetration testers, internal audit and external auditors check the work independently. We prepare environments, answer their questions and fix what they find.
How we work
How we deliver under change control.
Our usual seven stages, with the control points a regulated firm needs made explicit — and your compliance team involved where their input changes the design.
- 01
Discovery
Users, products and money flows mapped alongside the regulatory touchpoints: which providers hold which permissions, what data is processed, and who in your firm signs off what.
Scope, data map and sign-off owners
- 02
Strategy
Supplier due diligence runs in parallel with scoping, and we agree the controls — environments, access, audit logging, release approval — before quoting the build.
Agreed controls and fixed quote
- 03
UX & architecture
Your compliance team reviews prototypes and customer-facing wording before build, and journeys are instrumented with the events your Consumer Duty outcome monitoring needs.
Reviewed journeys and event plan
- 04
Development
Two-week sprints in which every change is ticketed, peer-reviewed and deployed through the pipeline, with a demo to you at the end of each sprint.
Traceable changes every sprint
- 05
Testing
Automated tests on money movement and permissions, duplicate and out-of-order events, and user acceptance testing in staging with your sign-off recorded.
Test evidence and UAT sign-off
- 06
Launch
Production deployment with monitoring, backups and a rollback plan, followed by a handover of code, credentials and documentation.
A live, documented product
- 07
Optimisation & support
Incidents handled to an agreed process, dependencies and security patches kept current, and production access reviewed with you on a set rhythm.
Support with an audit trail
Typical timeline
What the first months typically look like.
An example for a new customer-facing product built on a regulated partner’s APIs. The assurance steps run alongside the build, not after it.
An illustration, not a promise. Partner onboarding, due diligence and independent testing each have their own timelines, which often set the launch date more than the build does. You get a dated plan after discovery.
- Weeks 1–2
Discovery and due diligence
Journeys, money flows and data mapped; your supplier review started in parallel; controls, environments and sign-off owners agreed.
Scope, controls and fixed quote
- Weeks 2–4
Prototype and partner sandbox
Customer journeys prototyped and reviewed by compliance, and the partner’s sandbox APIs integrated to prove the riskiest flows early.
Reviewed prototype, working sandbox
- Build sprints
Build under change control
Two-week sprints, every change ticketed, reviewed and tested, with a demo to you at the end of each sprint.
Traceable, working software
- Before launch
Independent test and UAT
Penetration testing by an independent firm where you or your partner require it, findings fixed, and user acceptance testing signed off in staging.
Test evidence and sign-offs
- Launch and after
Controlled release
A release you approve, limits and monitoring in place, then access reviews, patching and incident handling on an agreed rhythm.
Live product with an audit trail
Engagement models
Ways to work with us on fintech.
Fintech work starts with a discovery sprint, where scope, controls and supplier due diligence are settled together. The build is then a fixed-price project, or a managed team for a longer roadmap.
Discovery sprint
From £2,000 fixed fee
You have an idea or a problem, but not yet a scope you would trust a quote against.
- Workshops with your team
- Prototype or technical spike
- Written scope, plan and estimate
Fixed-scope project
Quoted after discovery
A defined build — an MVP, a rebuild or a feature set — with milestones and a fixed budget.
- Agreed milestones and deliverables
- Milestone-based billing
- A demo at the end of every sprint
Managed product team
From £9,500 per month
A small cross-functional pod — engineering, QA and delivery lead — that owns an outcome.
- One accountable delivery owner
- Sprint planning and reporting
- QA and code review included
Prices are in GBP. Every estimate is confirmed in writing after a discovery call — the figures above are where engagements start, not a quote.
Relevant work
Fintech products we have built.
Payments, banking and wallet apps. Each case study covers the brief, the approach and the stack.
All case studiesFintech · Mobile
Sendora
Mobile-first money transfer and card app for a cross-border fintech.
React NativeNode.jsMapboxStripe
Read the case studyFinance · Mobile
Equity Bank
Digital banking app: accounts, bill payments, loans and investments.
React NativeNode.jsPostgreSQLAWS
Read the case studyFintech · Payments
e-Wallet
Multi-bank digital wallet with transfers, analytics and virtual cards.
React NativeNode.jsStripePostgreSQL
Read the case studyWhy Techsleight
What your compliance team will want to know.
Plain answers to the questions supplier due diligence usually asks.
Who you are contracting with
Techsleight Labs is a trading name of Krapton IT Consultancy, a UK company registered at 128 City Road, London EC1V 2NX. Your contract is with that company.
Where the work is done
By engineers based in the UK and India, on UK business hours, with production access limited to a named few.
How changes reach production
Through reviewed pull requests, automated tests, staging and a release you approve — the same route, faster, for urgent fixes.
What evidence exists
Ticket-to-release traceability, test results, release notes and access reviews, kept as a by-product of how we work.
How data is protected
Encryption in transit and at rest, secrets kept out of code, masked data outside production, and access removed when people leave the project.
How you would exit
You already own the code, cloud accounts and documentation, so an exit plan is a handover checklist rather than a negotiation.
What we will not do
Give legal or regulatory advice, or tell you a design meets FCA rules. Your compliance function decides; we build and evidence what they specify.
FAQs
Questions from compliance and procurement.
Straight answers on scope, cost, timelines and how we work. If yours is not here, ask us directly.
What can you provide for our outsourcing review?
Tell us what your policy requires at the start. We will go through it with you and say plainly what we can provide and what we cannot, before you commit to anything. What never needs negotiating is ownership: the code, cloud accounts and documentation are yours from day one.
How do you control who can access production?
Access is limited to named people you have agreed, granted per person rather than through shared logins, logged, and reviewed with you on a set rhythm. People lose access when they leave the project. Most engineering work needs no production access at all, which is how we prefer it.
How is a change approved before it reaches customers?
Every change is ticketed, reviewed by a second engineer, tested automatically and deployed through the pipeline to staging. You approve the release to production, and the approver is recorded against it. Urgent fixes follow the same route, just faster — never around it.
Do you use real customer data in development or testing?
No. We develop and test with synthetic or masked data, and live customer data stays in production. When investigating a production issue genuinely requires looking at live records, it happens under access you have approved, and it is logged.
Where are your engineers, and where will our data be processed?
Our engineers are based in the UK and India and work UK business hours. Your platform and data sit in your own cloud accounts — typically AWS’s London region for UK firms — and we document any access from outside the UK so your DPO can assess how it is covered.
What happens to our code and systems if we stop working with you?
They stay with you, because they were always yours: code, cloud accounts, documentation and credentials. We hand over a walkthrough of how everything is built, deployed and monitored, remove our own access, and confirm when that is done.
Can you work to our partner bank’s technical requirements?
Yes. Banking and e-money partners usually set requirements for security, data handling, testing and change notification, and may review how their programme partners work. We build to those requirements and join technical calls with the partner when that helps; if a requirement is something we cannot meet, we tell you early.
Will you support an independent penetration test?
Yes. Regulated firms and their partners often expect an independent test before launch and after major changes. We prepare a suitable environment, answer the testers’ questions, fix the findings and support the retest. We can run our own security testing too, but that would not count as independent.
How is a fintech project priced?
A discovery sprint starts from £2,000 and settles scope and controls; the build is then quoted as a fixed price with milestone billing. Longer roadmaps suit a managed team, from £9,500 a month. Documentation and control work appears as its own line in the quote, so you can see what it costs.
How long before we can launch?
The build is usually not the longest step. Partner onboarding, due diligence, independent testing and your own approvals each have their own timelines, so we plan them alongside the build from the first week. You get a dated plan after discovery that shows both tracks.
Start a project
Looking for a fintech software partner?
Tell us what you are building, which regulated providers are involved and what your compliance team will need from a supplier. We will reply with questions, a first view on approach and what discovery would cover.
What happens next
- 1A senior engineer reads your brief within one working day, and replies with questions or a first view.
- 2A 30-minute call to understand the goal, constraints and what good looks like — no sales script.
- 3A written proposal with scope, milestones, team and a GBP estimate you can take to your board.
Techsleight Labs is a trading name of Krapton IT Consultancy.
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