# Best AI Development Agencies for Team Extension

> 32 agencies. Top-ranked: Old St Labs, Square Root Solutions, Lexunit.

Canonical page: https://www.aiagencies.eu/services/ai-development/for/team-extension
Generated: 2026-09-28 · Curated by Gabor Kiss · No paid placements — inclusion, score, and rank are never sold.

## Ranked roster
Top 30 of 32 agencies on this page.

1. **Old St Labs** — London, United Kingdom · €45-85/hr (directory-listed) · team 50-249 · founded 2020 · services: AI Development, AI Consulting · 10 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/old-st-labs
2. **Square Root Solutions** — Dublin, Ireland · €20-40/hr (directory-listed) · team 10-49 · founded 2018 · services: AI Development, Generative AI · 10 documented client engagements with source URLs · reviewed 2026-09-16 · https://www.aiagencies.eu/agency/square-root-solutions
3. **Lexunit** — Budapest, Hungary · €45-85/hr (directory-listed) · team 10-49 · founded 2017 · services: AI Development, AI Automation, AI Consulting · 9 documented client engagements with source URLs · reviewed 2026-09-03 · https://www.aiagencies.eu/agency/lexunit
4. **Pixelette Technologies** — London, United Kingdom · €20-40/hr (directory-listed) · team 250+ · founded 2018 · services: AI Development, AI Agents, AI Consulting, Generative AI · 7 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/pixelette-technologies
5. **Stepwise** — Warsaw, Poland · €45-85/hr (directory-listed) · team 10-49 · founded 2016 · services: AI Consulting, AI Development, Generative AI · 6 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/stepwise
6. **Vention** — London, United Kingdom · €45-85/hr (directory-listed) · team 1000+ · founded 2002 · services: AI Development, AI Consulting, AI Agents · 10 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/vention
7. **Hiflylabs** — Budapest, Hungary · rate not published · team 250+ · founded 2015 · services: AI Consulting, AI Development, AI Automation · 8 documented client engagements with source URLs · reviewed 2026-09-03 · https://www.aiagencies.eu/agency/hiflylabs
8. **Transparity** — London, United Kingdom · €85-130/hr (directory-listed) · team 250+ · founded 2015 · services: AI Consulting, AI Development, AI Automation, AI Agents · 8 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/transparity
9. **Satalia** — London, United Kingdom · rate not published · team 50-249 · founded 2008 · services: AI Consulting, AI Development, AI Agents · 6 documented client engagements with source URLs · reviewed 2026-09-07 · https://www.aiagencies.eu/agency/satalia
10. **Version 1** — Dublin, Ireland · rate not published · team 250+ · founded 1996 · services: AI Consulting, AI Development, Generative AI · 6 documented client engagements with source URLs · reviewed 2026-09-03 · https://www.aiagencies.eu/agency/version-1
11. **Marionete** — London, United Kingdom · €45-85/hr (directory-listed) · team 10-49 · founded 2016 · services: AI Consulting, AI Development · 6 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/marionete
12. **Opinov8** — London, United Kingdom · €45-85/hr (directory-listed) · team 250+ · founded 2017 · services: AI Consulting, AI Development, AI Agents, Generative AI · 6 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/opinov8
13. **In The Pocket** — Ghent, Belgium · rate not published · team 250+ · founded 2010 · services: AI Development, Generative AI, AI Consulting · 5 documented client engagements with source URLs · reviewed 2026-09-07 · https://www.aiagencies.eu/agency/in-the-pocket
14. **craftworks** — Vienna, Austria · rate not published · team 10-49 · founded 2014 · services: AI Development, Generative AI · 5 documented client engagements with source URLs · reviewed 2026-09-07 · https://www.aiagencies.eu/agency/craftworks
15. **10Clouds** — Warsaw, Poland · €45-85/hr (directory-listed) · team 50-249 · founded 2009 · services: AI Agents, AI Development, Generative AI · 5 documented client engagements with source URLs · reviewed 2026-09-03 · https://www.aiagencies.eu/agency/10clouds
16. **Valletta Software Development** — Valletta, Malta · €45-85/hr (directory-listed) · team 50-249 · founded 2009 · services: AI Development, Generative AI, AI Agents · 5 documented client engagements with source URLs · reviewed 2026-09-24 · https://www.aiagencies.eu/agency/valletta-software
17. **Softblues** — London, United Kingdom · €45-85/hr (directory-listed) · team 10-49 · founded 2014 · services: AI Automation, AI Agents, AI Consulting, AI Development · 5 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/softblues
18. **Brights** — Warsaw, Poland · €20-40/hr (directory-listed) · team 50-249 · founded 2011 · services: AI Consulting, AI Development · 5 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/brights
19. **N-iX** — London, United Kingdom · €45-85/hr (directory-listed) · team 1000+ · founded 2002 · services: AI Consulting, AI Development, Generative AI, AI Agents · 4 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/n-ix
20. **Datamole** — Prague, Czech Republic · rate not published · team 50-249 · founded 2015 · services: AI Development, AI Consulting, AI Automation · 4 documented client engagements with source URLs · reviewed 2026-09-20 · https://www.aiagencies.eu/agency/datamole
21. **Sonalake** — Dublin, Ireland · rate not published · team 50-249 · founded 2016 · services: AI Development, AI Automation · 4 documented client engagements with source URLs · reviewed 2026-09-03 · https://www.aiagencies.eu/agency/sonalake
22. **peoly** — Prague, Czech Republic · rate not published · team 10-49 · founded 2019 · services: AI Development, AI Automation, AI Video · 6 documented client engagements with source URLs · reviewed 2026-09-20 · https://www.aiagencies.eu/agency/peoly
23. **Ultra Tendency** — Berlin, Germany · rate not published · team 50-249 · founded 2010 · services: AI Development, AI Consulting, Generative AI · 3 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/ultra-tendency
24. **Xomnia** — Amsterdam, Netherlands · rate not published · team 50-249 · founded 2013 · services: AI Consulting, AI Development, Generative AI · 3 documented client engagements with source URLs · reviewed 2026-08-04 · https://www.aiagencies.eu/agency/xomnia
25. **DEUS** — Amsterdam, Netherlands · rate not published · founded 2020 · services: AI Consulting, AI Development, AI Agents · 3 documented client engagements with source URLs · reviewed 2026-08-04 · https://www.aiagencies.eu/agency/deus
26. **Boldare** — Amsterdam, Netherlands · €45-85/hr (directory-listed) · team 50-249 · founded 2004 · services: AI Development, Generative AI, AI Consulting · 5 documented client engagements with source URLs · reviewed 2026-09-24 · https://www.aiagencies.eu/agency/boldare
27. **punktum digital** — Berlin, Germany · €45-85/hr (directory-listed) · team 2-9 · founded 2022 · services: AI Development, AI Consulting · 3 documented client engagements with source URLs · reviewed 2026-08-04 · https://www.aiagencies.eu/agency/punktum-digital-gmbh
28. **Grepton** — Budapest, Hungary · rate not published · team 50-249 · founded 2001 · services: AI Automation, AI Agents, AI Consulting, AI Development · 5 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/grepton
29. **WITH Madrid** — Madrid, Spain · rate not published · team 10-49 · services: AI Consulting, AI Development, Generative AI · 3 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/with-madrid
30. **Twistag** — Lisbon, Portugal · €45-85/hr (directory-listed) · team 10-49 · founded 2016 · services: AI Agents, AI Development, AI Automation · 2 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/twistag


## About this market
The team-extension evidence here runs longest, and it splits by what the embedded team spent its years on. In The Pocket names and dates its AI: Penny drafts replies to Bancontact Company's 8,000 monthly support tickets with OpenAI models under human verification, reported 75% faster, and three protocol tools were handed into EORTC's environment. Datamole's platform collects from more than 30,000 Lely milking robots across 5 million daily sessions and feeds a per-cow treatment model, eight years in. craftworks describes its experts inside several voestalpine data teams since September 2020. Twistag's Aralab accounts-payable agent shipped in six weeks with one engineer and handles more than 2,000 invoices a month.

Others document long engagements where AI is a minor line. Vention's EliseAI team ran four years, its Kafene team grew from two to seven engineers after November 2022, and three engineers spent three years on Comet's platform, yet the AI in those studies is automated replies and coding assistants. N-iX has run Gogo's data team since January 2017; Ultra Tendency's HUK-COBURG telematics platform has run since 2016 and its ECB platform migrated ninety-six processes, with no model in any case study. LANARS has been Defigo's engineering partner since 2018, and on its AI flagship the model work sat with a partner.

The sorting question is allocation: of the years documented, how many were the model. Ask each candidate to name the engineers who trained or evaluated a model at a named client, and whether those people would be on your team.

## Questions buyers ask

### How many AI agencies work with team extension on ai development?
32 agencies in our directory combine verified team extension client evidence with documented AI Development work. The current top-ranked are Old St Labs, Square Root Solutions, Lexunit — ordered by depth of documented client evidence, then our editorial scoring (portfolio quality, credibility, completeness); placement is never paid.

### How much does an AI agency cost for ai development?
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.

### How is the team extension model verified?
Every agency here documents team extension work on its own site or in a published case study, describing the engagement structure rather than a service-list claim. We never infer the model from portfolio tone, so this list only contains agencies that operate team extension engagements deliberately.

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Source: AIAgencies.eu — the curated register of European AI agencies. Rate provenance: "agency-confirmed" = disclosed via submission or claimed profile; "directory-listed" = Clutch or two agreeing B2B directories (lone unverified sources are never written). Full method: https://www.aiagencies.eu/methodology · Rate index: https://www.aiagencies.eu/rates