The quick version
How Clarvia Dev and Stack Builders position themselves — in their own words, and ours.
AI-first product development agency. We build AI products from the ground up — strategy, architecture, engineering, and deployment. AI is not something we added to an existing consultancy. It is what we were built to do.
NY + Ecuador-based software consultancy known for functional programming (particularly Haskell) and rigorous engineering practices. Stack Builders has a 6-year average client engagement length, offers a 2-week AI results guarantee, and focuses on code quality and reliability. They serve clients who value correctness and long-term maintainability.
Detailed comparison
A fair, category-by-category breakdown of how Clarvia Dev and Stack Builders compare.
Clarvia Dev
AI product development. We build products where AI is the core value proposition — not a module added to existing software. From LLM-powered applications to computer vision systems to AI automation tools.
Stack Builders
Software consultancy with strong functional programming roots and a growing AI practice. Stack Builders built their reputation on Haskell, Elm, and rigorous engineering. Their AI services — including a 2-week results guarantee — are a newer addition to a consultancy grounded in traditional software development.
Clarvia if AI is the core of what you are building. Stack Builders if you need a broader software consultancy with strong engineering practices and some AI capability.
Clarvia Dev
AI-native. Our team works with LLMs, ML pipelines, vector databases, embedding systems, and production AI infrastructure daily. We hire and train for AI product development specifically.
Stack Builders
Stack Builders has added AI services to their consultancy offering and their 2-week results guarantee shows commitment. Their engineering rigour is genuine. However, their DNA is functional programming and traditional software — AI is an acquired capability rather than a founding one.
Clarvia for deep, native AI expertise. Stack Builders if engineering rigour and code quality matter more than AI-specific depth.
Clarvia Dev
Project-based and retainer engagements. We focus on delivering a product outcome, then either hand off or continue iterating. Engagements are defined by what gets built, not by how long we stay.
Stack Builders
Long-term partnerships. Stack Builders' 6-year average client engagement length is remarkable and speaks to genuine relationship quality. They become embedded partners in their clients' technology teams. This is a real strength for ongoing software development.
Stack Builders if you want a long-term technology partner embedded in your organisation. Clarvia if you want a focused AI product engagement with a clear deliverable and timeline.
Clarvia Dev
Working AI prototype in 2-4 weeks. We move fast because we know AI product patterns and can apply them immediately. Less time planning, more time building.
Stack Builders
2-week results guarantee for AI work. This is a strong promise and shorter than many competitors. However, "results" in their context typically means demonstrating feasibility, not shipping a production-ready product.
Both deliver early results quickly. Clarvia if you need a production-bound prototype. Stack Builders if a feasibility demonstration within 2 weeks gives you the confidence to proceed.
Clarvia Dev
Pragmatic and product-focused. We choose technologies that are best for the AI product being built — Python, TypeScript, Rust, whatever fits. Correctness matters, but so does shipping.
Stack Builders
Functional programming heritage with emphasis on correctness and type safety. If your project benefits from Haskell or Elm, Stack Builders is one of the best in the world. If your AI project needs the broader Python/ML ecosystem, their FP-first approach may not be the ideal fit.
Clarvia for AI-optimised technology choices. Stack Builders if you value functional programming rigour and have a project where Haskell or similar languages are a good fit.
The honest recommendation
Both companies do good work. The right choice depends on what you actually need.
Choose Clarvia Dev when...
AI is the core of your product, not a feature added to existing software
You need deep expertise in LLMs, ML pipelines, and AI product architecture
You want a focused product engagement with clear deliverables and a defined timeline
Your project lives in the Python/ML ecosystem and needs AI-native tooling decisions
Speed to a production AI product matters more than long-term consulting partnership
Choose Stack Builders when...
You value long-term consulting partnerships — their 6-year average engagement speaks volumes
Your project benefits from functional programming and strong type safety (Haskell, Elm)
Engineering rigour and code correctness are your top priorities
You want a consultancy that becomes a deeply embedded part of your technology team
You need both traditional software development and some AI capability from one partner
Common questions
Stack Builders has a 2-week AI results guarantee. How does that compare to Clarvia?
Both Clarvia and Stack Builders commit to showing results fast. The difference is in what you get. Stack Builders' 2-week guarantee typically delivers a feasibility demonstration — proof that AI can work for your use case. Clarvia's 2-4 week prototype is a working product that users can interact with and provide feedback on. Both have value; the question is what stage your project is at.
Does Stack Builders' functional programming background make them better at AI?
Functional programming produces excellent software engineers. The rigour, type safety, and correctness focus that Stack Builders brings is genuinely valuable. However, the AI/ML ecosystem is overwhelmingly Python-based. Most ML frameworks, model libraries, and data tools are built for Python. An AI-native team working in the native ecosystem of ML tooling will generally move faster on AI-specific work.
Stack Builders keeps clients for 6 years on average. Why should I consider a project-based agency instead?
That retention rate is impressive and reflects real quality. Long-term partnerships work well for ongoing software development. But if your need is "build an AI product and ship it," you may not need a 6-year relationship. Clarvia delivers a focused product engagement, then either transitions to a retainer or hands off. Not every project needs a lifelong partner.
Can Clarvia match Stack Builders' code quality?
Stack Builders' Haskell heritage means they take code quality seriously — that is a real cultural strength. Clarvia also prioritises production quality, test coverage, and maintainability, but with AI-specific tooling and patterns. The code quality question is less about who writes better code and more about who writes the right code for AI products specifically.
Building an AI product that needs AI-native expertise?
Book a free 30-minute call. We will discuss your project and show you what a focused AI product engagement looks like.