Services
The kinds of work we do
Kestrel Systems builds software for companies that move goods or money. Three kinds of work, one engineering team — below is what each one means in practice and who it is for.
Custom software development
Product teams that take an idea from a whiteboard to a system your business runs on — web applications, internal tools and the APIs behind them, built to be handed over and maintained.
What it is
We design and build software that does not come out of a box: web applications, internal tools, back-office systems and the APIs that hold them together. A small team takes the work from the first scoping conversation through architecture, delivery and release, so the people writing the code are the people who understood the problem. We work in short cycles with something runnable at the end of each one, which is how a plan survives contact with reality. Everything is documented, tested and handed over so your own team can keep it running after we step back.
Who it is for
For companies whose work no longer fits a standard product, and who need a bespoke system they will own.
- Companies that need a bespoke product rather than an off-the-shelf tool
- Teams replacing spreadsheets or an ageing internal system
- Businesses with no in-house engineering team, or one that is already at capacity
Integration for logistics companies
Warehouse, transport and delivery systems rarely speak the same language. We connect them — carrier APIs, EDI, tracking and ERP data — so an order stays one order from pick-up to proof of delivery.
What it is
Logistics runs on systems that were never designed to talk to each other: a warehouse management system here, a transport planner there, a dozen carrier APIs and a customer who wants one tracking link. We build the integration layer in between — carrier and courier APIs, EDI messages, ERP and WMS data, event feeds and tracking updates — and we make it observable, so a failed message is something you can see and replay instead of a parcel that quietly disappears. We work with the volumes and the peaks that come with the industry, and we test against the messy data that real operations produce.
Who it is for
For logistics and freight operators whose systems have to agree with each other before an order can move.
- Logistics, transport and freight operators
- Carriers, couriers and freight forwarders
- Warehouse, fulfilment and last-mile delivery businesses
Payments and fintech engineering
Payment flows, ledgers and banking integrations built for money that has to balance: careful reconciliation, auditable records and engineers who are comfortable working inside a regulated environment.
What it is
Software that moves money has a different standard of done: it has to balance, it has to be auditable, and it has to behave predictably when something upstream fails. We build payment flows, ledgers, reconciliation and reporting, and we integrate with payment providers, card schemes and banking APIs. Idempotency, retries, settlement and a clear audit trail are designed in from the start rather than added after the first mismatch. We are used to working alongside compliance and finance teams, and to writing the kind of documentation an auditor will ask for.
Who it is for
For fintech, payment and e-commerce businesses that need money flows they can reconcile and explain.
- Fintech and payment companies
- Banking and financial services teams building new products
- E-commerce and marketplace businesses handling payouts
Not sure which of these you need?
Most projects touch more than one of them. Describe the problem in a few lines and we will tell you honestly whether it is work we should be doing.