Custom Software Development

Software Shaped Around Your Business

When the off-the-shelf tool almost fits, the gap is where your margin goes. We build the system that closes it — and hand you the keys, the tests and the documentation with it.

Scope Your Platform See how we work

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Overview

Bespoke systems, built to be handed over

Custom software earns its cost when it encodes something specific to how you operate. It loses that cost the moment only one team can maintain it. We build for the handover from the first commit — clear boundaries, real tests, and documentation written while the reasoning is still fresh.

What that means in practice

Domain before framework. We model your process first and pick the stack second. The reverse is how you end up shaping the business around a tool.
Seams you can replace. Clear module boundaries and explicit interfaces, so swapping a payment provider or a warehouse system is a contained change.
Tests that mean something. Coverage on the logic that would cost you money if it broke, not a percentage chased for its own sake.
No lock-in to us. Your repository, your infrastructure, your runbooks. If you take the system in-house next year, that is a successful outcome.

Yours to keepCode, tests and runbooks

Start With A Discovery Call

What we build

Systems, integrations and the migrations

Ten engagements covering greenfield platforms, the legacy estate around them, and the route from one to the other.

Screens showing performance charts and metrics

Why teams pick us

Why choose SysStacks?

We model the domain first

Your process, in your language, agreed before code. Frameworks are an implementation detail and get picked later.

Boundaries you can act on

Explicit modules and interfaces, so replacing one supplier or subsystem does not mean re-opening the whole platform.

Tests where the money is

Pricing, permissions, billing, state transitions — the logic that hurts when it is wrong gets covered first.

Documentation as you go

Decisions recorded when they are made, not reconstructed at handover from memory and commit messages.

Built for your team to own

Runbooks, environments and onboarding notes included. Continuing with us should be a choice, never a dependency.

How we deliver

How a custom build proceeds

Six stages, one continuous loop — software you keep needs a rhythm, not a finish line.

Discovery & domain mapping

We sit with the people doing the work, map the process as it really runs, and write down the rules that are currently in someone’s head.

Architecture & sequencing

A design with the boundaries drawn, plus a build order that puts the riskiest assumption first rather than the easiest feature.

Iterative build

Two-week increments against working software, with the domain model and tests evolving together instead of one chasing the other.

Verification & UAT

Automated coverage on the critical logic, plus structured user testing with the people who will live in the system daily.

Migration & cutover

Data moved with reconciliation, users trained, and a parallel-run period where the old system is still there if we are wrong.

Support & handover

We operate it, document it, and — when you want — teach your team to take it. The exit path is part of the plan from day one.

Industries we focus on

Custom systems we build for operating businesses

Manufacturing & industrial

Production scheduling, quality and non-conformance tracking, and OEE reporting built around the line as it actually runs, not the diagram of it.

Logistics & supply chain

Dispatch, exception handling and carrier integration, with the edge cases that consume a planner’s day treated as core flows.

Financial services

Reconciliation, approval workflows and audit trails, designed so every state change can be explained to a regulator later.

Healthcare & clinical operations

Scheduling, records and referral systems built around HIPAA and GDPR obligations, with data handling agreed before development starts.

Property & professional services

Matter, portfolio and case management for firms whose process is their product and does not fit a generic CRM.

Talk Through Your Requirements

Our tech stack

The languages and platforms we build in

Chosen for the shape of the problem, the team that will inherit it, and how long it needs to run.

TypeScript

Node.js

Python

Java

.NET

Rust

PHP

Laravel

Django

Spring

PostgreSQL

MySQL

SQL Server

MongoDB

Redis

Kafka

RabbitMQ

Docker

Kubernetes

Terraform

GitHub Actions

SonarQube

Featured insights

Stories of our transformations across services and industries

From concept to completion.

Explore More

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Case StudySilver Jeans — a commerce platform rebuilt around the customer

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BlogA governance checklist to clear before your first fine-tune

BlogThe uptime math behind a 99.98% commitment

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Case StudyMeridian Freight — visibility across a fragmented network

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Case StudyHalcyon Insurance — claims handling rebuilt end to end

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Case StudyArgent Energy — operations data in one place at last

Get in touch

Tell us what your business does that no product quite handles. An engineer — not a sales rep — replies within one business day.