Custom software development
Software built around your operation, not the other way round
We build and maintain web applications, APIs and internal tools for companies that move physical goods and sell online. Our stack is .NET and SQL, our habit is to ship small and often.
Off-the-shelf software covers the first 80% of most businesses. The remaining 20% is where margins, speed and customer experience are decided: the pricing rule that depends on three systems, the report your warehouse manager rebuilds in a spreadsheet every Monday, the handover between your store and your carrier that still needs a human.
That is the work we take on. We design the data model, write the code, run it in production and keep it running. Clients own their data; the platforms and libraries we bring stay ours, so you never pay to rebuild commodity parts.
Projects are scoped in writing and delivered in increments you can test with real orders. Larger systems typically start as a small vertical slice that goes live early and grows from there.
What's included
- Discovery, data model and architecture
- Web applications and admin back-offices (ASP.NET Core)
- REST APIs, webhooks and EDI endpoints
- Automation of repetitive operational tasks
- Reporting and dashboards on SQL Server or PostgreSQL
- Deployment on Linux/Docker or Windows/IIS
- Maintenance, monitoring and version updates
How we work
A project in four moves
Understand
We shadow the process, read the existing data and write down the real requirements, including the inconvenient ones.
Slice
The first release is the thinnest useful version of the system, live within weeks, so feedback comes from use, not from slides.
Grow
Features are added in short cycles with automated tests behind them. You see progress in a running system every week.
Operate
We keep the system patched, monitored and documented, and we train the people who use it.
A good fit if
This service fits you if
- You run a warehouse, a fulfilment business or an online store with workflows software vendors don't cover
- You need an API or integration layer between systems that were never meant to talk
- You have a spreadsheet or a manual process that has become business-critical
- You want one team to design, build and operate the system long term
Not sure whether to build or buy?
Tell us what you are trying to do. If a product on the market already solves it, we will say so and help you set it up.
Get in touchFAQ
Frequently asked questions
Which technologies do you use?
Mostly .NET (C#, ASP.NET Core) with SQL Server or PostgreSQL, running on Linux containers or Windows/IIS. For front-ends we use server-rendered pages or React, depending on the product. We prefer boring, well-supported technology over novelty.
Who owns the code?
Data entered into the system is yours. Software, libraries and integrations we develop remain GuneSys intellectual property and are licensed to you for the term of the agreement, which keeps fees low because commodity parts are reused across clients. Full assignment of custom code can be agreed separately for bespoke projects.
How do you price projects?
After a discovery call you receive a written scope with a fixed price or a capped time-and-materials estimate. Ongoing operation is a fixed monthly fee. All invoices are in USD.
Can you take over an existing system?
Yes. We regularly inherit legacy .NET and SQL systems, stabilise them, add monitoring and then modernise them step by step while they keep running.
Have a project, an integration or a warehouse to run?
Tell us what you are building. We reply within one business day with a clear next step.