Software systems, built and maintained to hold up.
An independent practice for web applications, integrations, and the business systems underneath them.
Services
Web application development
Custom applications built around how the work actually gets done, not around a template. Delivered in working increments, so the shape of the thing is visible long before it is finished.
Systems and API integration
Connecting tools, services, and data that were never designed to talk to each other. The goal is that records move reliably and that failures surface loudly instead of quietly.
Platform maintenance and modernization
Keeping working software working as dependencies, traffic, and requirements change underneath it. Aging systems are modernized in place where that is the honest answer, and replaced only where it is not.
Technical consulting
Architecture review, feasibility assessment, and a second opinion before a decision becomes expensive to reverse. The deliverable is a written recommendation you can act on without me.
Approach
Direct collaboration
You talk to the person writing the code. Nothing is relayed through an account manager, and no context is lost on the way.
Clear scope, honest estimates
Scope is written down before work starts. When an estimate is uncertain, that gets said plainly rather than padded quietly.
Documentation as delivery
Handoff notes, runbooks, and architecture decisions ship with the code. A project is not done when it works, it is done when someone else can run it.
Maintainability over speed
Code is written to be read a year from now, by someone who was not in the original conversation. Short-term velocity that costs long-term clarity is not a trade worth making.
About
Invariant Systems is an independent practice run by a senior full-stack engineer with more than twelve years across e-commerce platforms, ERP integrations, and custom business systems. Navy veteran. Based in Central Florida, working remotely worldwide.
An invariant is a condition that holds true at every step of a program’s execution. That is the standard the work is built to.
Contact
Invariant Systems, LLC is a Florida limited liability company and is fully insured. To describe a project in detail, use the project form.