AI Development × Startups
AI Development Agencies for Startup Clients (November 2026)
AI Development agencies with verified startup client evidence — ranked by depth of documented work, then editorial quality.
Each listed agency evidences at least 2 documented startup clients. Combined, the agencies below document 213 client engagements.
Ranked AI Development agencies for startup clients
Rankings updated · Newest review
Top 30 of 31 agencies with documented startup work.
London, United Kingdom
Client evidence: 29 documented clients overall · Early-stage
Best for: Founders and small UK firms building a first web or mobile product with an LLM feature inside it.
Dublin, Ireland
Client evidence: 20 documented clients overall · Early-stage
Best for: Irish and European SMEs and founders buying a whole product build, with AI as one layer inside it rather than the whole engagement.
London, United Kingdom
Client evidence: 13 documented clients overall · Early-stage
Best for: Founders commissioning a first blockchain or AI product build on a startup budget who will check references before signing.
Modulai
#4Stockholm, Sweden
Client evidence: 12 documented clients overall
Best for: Product teams that need a model shipped into production, from clinical retrieval to real-time vision on constrained hardware.
Stepwise
#5Warsaw, Poland
Client evidence: 11 documented clients overall · Early-stage
Best for: Early-stage B2B software companies that need a cloud and data engineering team, with AI as one part of the product build.
Tallinn, Estonia
Client evidence: 10 documented clients overall · Early-stage
Best for: Seed-stage founders who want an LLM feature or a data-extraction pipeline built into a product by the same team that ships the app.
Vention
#7London, United Kingdom
Client evidence: 10 documented clients overall
Best for: Venture-backed product companies adding engineers to an existing team, with AI as one feature inside the software work.
InData Labs
Verified: the agency confirmed ownership from a company email address, and the listing passed editorial review#8Vilnius, Lithuania
Client evidence: 7 documented clients overall · Early-stage
Best for: Product teams with a defined forecasting, fraud or analytics problem who want an established ML team on fixed-price or dedicated terms.
Warsaw, Poland
Client evidence: 7 documented clients overall · Early-stage
Best for: Data-rich firms and startups with a detection, vision or forecasting problem suited to a research-led team.
Tallinn, Estonia
Client evidence: 7 documented clients overall · Early-stage
Best for: Funded startups that need the interface and front end of an AI product designed and built while the model stays in-house.
Vstorm
#11Wrocław, Poland
Client evidence: 6 documented clients overall · Scale-ups
Best for: Mid-market operators putting an agent inside a product or a clinical workflow, where output has to be validated before it ships.
Yield Studio
#12Lyon, France
Client evidence: 6 documented clients overall · Scale-ups
Best for: French mid-market firms adding a document-analysis or automation layer to a SaaS or internal platform they already operate.
Opinov8
#13London, United Kingdom
Client evidence: 6 documented clients overall · Early-stage
Best for: Teams adding cloud, data or modernization engineers who want AI coding tools applied to that delivery.
Sparkbit
#14Warsaw, Poland
Client evidence: 5 documented clients overall · Early-stage
Best for: Early-stage product companies that need the ML core of their product built, tested and handed over with the IP.
Tooploox
#15Wrocław, Poland
Client evidence: 5 documented clients overall · Scale-ups
Best for: Product teams needing an ML problem researched and built from scratch—no dataset, no proven approach—not an off-the-shelf integration.
Upside Lab
#16Kraków, Poland
Client evidence: 5 documented clients overall · Scale-ups
Best for: Teams that need governed, compliant data foundations before AI—healthcare research platforms or commerce running on real customer data.
Indigo Labs
#17Ljubljana, Slovenia
Client evidence: 5 documented clients overall · Early-stage
Best for: Product teams that want a scoped AI build with the duration, team size and budget stated before the contract.
Buildo
#18Milan, Italy
Client evidence: 5 documented clients overall · Scale-ups
Best for: Scale-ups and regulated medtech firms that need an ML or LLM feature built into an existing product by a full-stack team.
Valletta, Malta
Client evidence: 5 documented clients overall · Early-stage
Best for: Small firms and startups that want one embedded engineer to wire an LLM or agent into their existing tools on a modest budget.
Softblues
#20London, United Kingdom
Client evidence: 5 documented clients overall · Early-stage
Best for: Early-stage B2B product teams and smaller UK or Irish firms scoping a first voice agent, agent pipeline or Claude rollout.
Rotterdam, Netherlands
Client evidence: 5 documented clients overall · Early-stage
Best for: Scale-ups adding an AI feature to a product they already run, where the model is bought and the surrounding app must be built.
Imobisoft
#22London, United Kingdom
Client evidence: 4 documented clients overall · Early-stage
Best for: Health and industrial companies taking a risk-scoring or compliance-reporting workflow from paper to a regulated digital platform.
xtream
#23Milan, Italy
Client evidence: 4 documented clients overall · Scale-ups
Best for: Utilities, lenders and scale-ups with a defined forecasting or planning problem and the data to feed it, handed over as a production model.
TechnoLynx
#24Budapest, Hungary
Client evidence: 4 documented clients overall · Early-stage
Best for: Hardware, codec and vision startups that need a model or GPU pipeline made faster, ported or validated, with a benchmark they keep.
B13 AI
#25Birmingham, United Kingdom
Client evidence: 4 documented clients overall
Best for: UK founders and small product teams who need a build partner at UK-regional rates, with AI as one component of a wider system.
Softspring
Verified: the agency confirmed ownership from a company email address, and the listing passed editorial review#26Madrid, Spain
Client evidence: 3 documented clients overall · Early-stage
Best for: Founder-led products that need one AI feature built properly, with the data boundary and the human checkpoint decided up front.
Berlin, Germany
Client evidence: 3 documented clients overall · Early-stage
Best for: Founders putting a model inside a consumer health, sports or wellbeing product.
Madrid, Spain
Client evidence: 3 documented clients overall · Early-stage
Best for: Early-stage founders in Spain who need a product built quickly and will scope any real model work separately.
Rotterdam, Netherlands
Client evidence: 2 documented clients overall · Early-stage
Best for: Founders and small teams who need a working AI feature in production fast, with the compliance reasoning written down.
Altar.io
#30Lisbon, Portugal
Client evidence: 2 documented clients overall · Early-stage
Best for: Funded founders building a regulated fintech or commerce product who want engineering that carries them to the next raise.
About this list
AI development for startups is product engineering under runway pressure: a working feature in weeks, at a cost the cap table survives, in code the founding team can own. The strongest agencies here document exactly that shape. Modulai's client list runs from Fishbrain's trip forecasting for millions of anglers to meal detection in a diabetes app—scoped ML systems priced for growing companies, delivered by the team the case studies name. punktum digital shipped deep-learning diagnostics into DiaperID's infant-health app and the computer vision inside a smart animal-diagnosis collar. Sputnik Digital built Invntry's image-identification system for home-insurance inventories and Hollr's generative video platform. Sparkbit publishes model metrics next to the handover: a tower-equipment detector for 5x5 Technologies retrained from F1 0.72 to 0.86, with the transfer to the client's team reported in the study.
Three questions protect a startup buying development. Speed: what shipped in the last eight weeks, for whom? Ownership: who keeps the code, and what runs without the agency—a system only the vendor can operate is a liability at diligence. And scope discipline: the strongest startup engagements on this page were bounded builds with acceptance criteria, not open-ended retainers. Buy the bounded version; extend it when it works.
Intro by Gabor Kiss, curator · How we rank
Expert Insight
Why startup fit matters for AI Development
Startup budgets buy scoped builds, not programs—the agencies here document work shipped in weeks to months, priced for companies that measure runway.
At small agencies the case-study authors are the delivery team, which removes the seniority lottery that makes large firms risky for small engagements.
Code ownership decides whether the engagement was an asset or a dependency: every documented build here describes a system the client runs, and that question belongs in your first call.
Frequently asked questions
31 agencies in our directory combine verified startup client evidence with documented AI Development work. The current top-ranked are Old St Labs, Square Root Solutions, Pixelette Technologies — ordered by depth of documented client evidence, then our editorial scoring (portfolio quality, credibility, completeness); placement is never paid.
Published rates across this page's agencies run €20–130 per hour (median ~€65). Project totals depend on scope — the rate index at /rates breaks the computed bands down by region, country and team size.
Each listed agency has at least two documented, named startup clients — published case studies or engagement descriptions our research actually read, with source URLs stored per client. Logo walls without published evidence carry no weight, which is what separates this list from self-declared directories.
10 of the agencies on this page document an embedded / team-extension working model. See the team-extension page for the full verified list, or check the engagement chips on individual profiles.