We build and run the software your business depends on.

CLR3 is a software consulting, advisory and product development company. We design, build and run production systems for our clients, and we run our own products on the same foundations.

Start a conversationSee what we operate

What we do

  • Software consulting
  • Technical advisory
  • Product development
  • Managed operations

Senior engineers only. We work in your repositories, in your cloud and with your process.

Products built and operated by CLR3

Three ways to work with us

Most engagements start with one and grow into the others. All of them are staffed by senior engineers who have shipped and run systems like yours.

Consulting

Senior engineers working inside your team, from architecture to production.

We take on the hard, well-defined problems: systems that need to be faster, cheaper, more reliable, or simply finished. We work in your codebase and follow your process, and we leave things better documented than we found them.

  • Architecture and system design
  • Distributed and event-driven systems
  • Performance and reliability engineering
  • Platform, infrastructure and DevOps

Advisory

Technical judgment for founders, boards and leadership teams.

Fractional CTO and advisory work for companies facing decisions they can't easily undo. What to build, what to buy, who to hire, and when to rewrite. You get direct opinions from people who have run these systems themselves.

  • Fractional CTO and technical leadership
  • Technical due diligence
  • Roadmap, build-vs-buy and vendor strategy
  • Engineering organisation and hiring

Product development

Complete software products, from the first commit to day-to-day operations.

We design, build and run whole products: APIs, data pipelines, real-time systems and the interfaces on top of them. The team that builds it also ships it, monitors it and owns it in production.

  • Zero-to-one product builds
  • Real-time data and streaming platforms
  • AI-enabled product features
  • Managed operations and SRE

Products we build and operate

These are not side projects. Each one runs in production for paying customers, on infrastructure we own and operate. They are the best evidence of how we work.

How an engagement runs

Four phases, the same whether we are advising, building for you or building with you. The order matters. We don’t write code for a system we don’t understand yet.

  1. 1Discover

    Understand the system before touching it

    A short, focused look at your code, infrastructure, data and the people running it. You get a written assessment and a plan with honest estimates.

  2. 2Design

    Decide what to build, and what not to

    We agree on architecture, interfaces and trade-offs up front, in documents you keep. Boring technology where it works, new technology where it earns its place.

  3. 3Build

    Ship in weeks, in your repository

    Small senior teams, continuous delivery, visible progress every week. There is no hand-off at the end because there is no separate delivery team.

  4. 4Operate

    Run it, measure it, improve it

    Monitoring, on-call and cost discipline from day one. We run our own products this way and we bring the same habits to yours.

What you can expect

Operators, not just builders
Every product listed here is run by us, in production, for paying customers. Our advice comes from on-call hours, not slide decks.
Senior by default
Small teams of experienced engineers. You talk to the people writing the code.
Performance is a feature
Most of our work lives in latency-sensitive, high-throughput systems. We measure everything and design for the p99.
Your code, your cloud, your IP
We work in your repositories and your accounts. When the engagement ends, nothing is held hostage.

Tell us what you’re building.

A short note is enough. A senior engineer replies, usually within one business day.

Email
hello@clr3.org
Careers
8 open roles

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