Turn your product uncertainty into evidence investors trust.

That's completely fine. Many founders arrive with rough concepts, early prototypes, or hypotheses they want to explore. Part of the process is helping clarify the idea, define the core assumptions, and turn it into something testable. A fully formed product is not required to start.

No. The MVP Sprint is designed for exactly this situation — transforming an idea, prototype, or early vibe-coded experiment into a validation-ready MVP that can generate real market signals.

Some products can be validated within a single sprint. Others require additional iterations. The goal is always the same: launch the smallest possible version capable of generating meaningful evidence. Typical paths are MVP + 1 or MVP + 2 validation sprints.

Depends on the product and ICP. Common experiments include targeted outreach, landing page tests, early advertising, community distribution, founder-led sales, and user interviews. The experiments chosen are matched to what will generate the clearest signal for that specific product.

Founders typically move into the First Traction stage, focusing on scaling promising acquisition channels, refining onboarding, and improving product positioning. For founders preparing to raise, positive signals from validation sprints serve as concrete proof points for investor conversations. Some teams continue through paid engagements; in select cases, we explore deeper partnerships.

Primary focus is early-stage startups and founders exploring new product ideas. We also work with product teams inside larger companies and innovation teams testing new concepts.

Yes. If a product shows promising validation signals, we help refine the pitch narrative, structure traction metrics, and prepare investor materials. The evidence produced during validation sprints often becomes the foundation of the investor deck. In some cases we introduce founders to members of our angel investor network.

Some teams stop after validation with clarity about the market. Others continue building and scaling. We often continue as a product, growth, and technical partner as the product evolves.

A traditional MVP is often built to launch a product. A validation MVP is built to test a specific hypothesis. The goal is not to ship a product — it is to generate the clearest possible signal about whether the idea has real demand. This means the validation MVP is smaller, more focused, and optimized for learning rather than for completeness or polish.

Real market signals are measurable evidence that actual people respond to the product in a meaningful way. This includes things like unprompted signups, willingness to pay, repeated usage, referrals, or direct requests for access. The key distinction is between activity (clicks, traffic, likes) and evidence (behavioral proof that someone wants the product enough to act on it). Proof Engine is built around generating and correctly interpreting the difference. These are the signals investors use during due diligence to evaluate whether a product has real traction potential.

Yes — this is actually one of the most common situations we work with. A product with no traction is not necessarily a failed idea. It often means the wrong assumptions were tested, the wrong audience was targeted, or the demand experiments were not structured to generate clear signals. We start by diagnosing what was tested and what was not, then run structured validation experiments to find out whether demand exists and where.

The core principle is to test the riskiest assumption first, with the smallest possible artifact. That might be a landing page, a prototype, a manual concierge process, or a focused outreach campaign — before any significant engineering. The MVP Sprint is designed to build exactly the minimum needed to run a real demand test, not a complete product. Most ideas can be meaningfully tested within two to four weeks.

A traditional agency is optimized for building software to a defined spec. Proof Engine is optimized for reducing product risk before committing to a full build. The starting point is different: we begin with hypotheses and experiments, not a feature list and a timeline. The output is also different: instead of a codebase, the primary deliverable is market evidence — the kind that helps founders build and investors decide. We build software as a means to that end, not as the end itself.

A discovery phase typically produces a document — user research, a requirements spec, a roadmap. A validation sprint produces evidence. The difference is that validation sprints end with real market signals from real users, not a set of internal recommendations. Discovery informs what to build. Validation tests whether it is worth building at all.

Each sprint — MVP Sprint or Demand Validation Sprint — is priced at $4,500 and runs for two weeks. The MVP Sprint covers hypothesis definition, MVP scoping, build, and preparation for demand testing. The Demand Validation Sprint covers experiment design, user outreach, demand testing (ads, landing pages, or direct outreach depending on the product), analytics setup, and signal interpretation. Most founders start with both sprints in sequence, with a total starting budget of $9,000 for approximately four weeks of work.

The most common entry point is a single MVP Sprint at $4,500. For founders who already have a working MVP and want to jump directly to demand testing, starting with a Demand Validation Sprint is also an option. The best way to figure out the right starting point is a short discovery call — book one at cal.com/kirylartsymenia.

Yes. AI-native products are a primary focus. We have experience building and validating products that use LLMs, AI agents, and automation workflows across outbound sales, creator tools, workflow automation, and other domains. Validating an AI product has unique challenges — user expectations are often misaligned, and the real job-to-be-done is frequently not what founders initially assume. We help surface those gaps early.

AI-native means that AI tools and agent systems are embedded into the core of how the product is built and tested — not bolted on as features. In practice this means using LLM orchestration, automated outreach, AI-assisted prototyping, and agent-driven workflows to compress weeks of work into days. This is how a two-week sprint produces meaningful output rather than a rough prototype.

Very little. Most founders arrive with an idea, a rough hypothesis, or an early prototype. Before the sprint begins, we typically ask for a short written summary of the idea, the assumed target customer, and the core problem being solved. No spec, no PRD, and no existing code is required. The first part of the MVP Sprint is designed to formalize exactly these inputs.

For an MVP Sprint: Week 1 focuses on hypothesis definition, MVP scoping, and early build. Week 2 focuses on completing the build, preparing the product for testing, and handing off a launch-ready validation MVP. For a Demand Validation Sprint: Week 1 covers experiment design, outreach setup, and launching the first demand tests. Week 2 focuses on running experiments, collecting signals, analyzing results, and producing a clear recommendation about next steps.

Yes. Beyond validation sprints, Proof Engine takes on full-cycle product development engagements — from architecture and backend to frontend and AI integrations. Where needed, we bring in a trusted partner network covering specialized areas including mobile, design systems, data engineering, and growth infrastructure. The right team is assembled based on what the product actually requires.

Yes. For products that show strong signals and founders who want a deeper collaboration, we offer two formats beyond sprint engagements. The first is ongoing paid development — a continuous product and growth partnership covering engineering, experimentation, and iteration. The second is a joint venture structure for select products where we see high conviction on both sides: deeper involvement, shared ownership, and aligned upside. We also bring in a trusted partner network for specialized areas — mobile, design systems, data engineering, growth infrastructure — depending on what the product requires at each stage.

Yes. Validation-first is our default approach because it reduces risk — but it is not a requirement. If a product direction is already validated and the team is ready to build, we can engage directly as a development partner. We bring the same AI-native execution speed and the same partner network regardless of where in the product lifecycle a team is starting from.

Yes. The primary output of a validation sprint is structured market evidence — demand signals, user behavior data, and traction indicators. This is exactly what investors evaluate during due diligence. Several founders have used sprint outputs as the core evidence in their pitch decks and investor conversations.

Investors want evidence that the problem is real, the demand is measurable, and the unit economics are defensible. A single MVP + Demand Validation cycle can produce evidence across all three. Start with the assumption your investors are most skeptical about.