Bob van Luijt
About Bob van Luijt
Bob van Luijt is a Dutch technology entrepreneur based in Amsterdam. He is the co-founder and CEO of Weaviate, an open-source vector database. Weaviate was originally built by SeMI Technologies, the company he co-founded. Tracxn dates his startup activity to 2019 through SeMI. Etienne Dilocker is his co-founder.
He has said he started his first internet business at 15, building websites for small companies. He studied jazz and electronic composition at ArtEZ, then music at Berklee College of Music in the US, while running his software business on the side. He also completed a Harvard Business School executive program. A third-party profile says he previously ran a tech consultancy whose clients included ING and Elsevier, and that he chairs the Creative Software Foundation.
He speaks regularly on open source, software business and vector search. In 2021 he gave a TEDx talk on the relationship between language and software. His personal site is txt.vanluijt.nl, and he posts on X as @bobvanluijt.
Lounge's existing note, based on Crunchbase, counts 24 investments for Bob van Luijt, 17 of them in AI since 2023. Crunchbase lists no lead investments, no exits and no companies founded under his investor profile. Its public profile has since updated to 28 investments, and Tracxn lists 30. Counts differ by database, so treat them as approximate.
His recent activity on Crunchbase includes Bloom (pre-seed, September 2025), Polars (Series A, September 2025), P-1 AI (seed, April 2025), Cartesia (December 2024), Dash Bio (October 2024), Trace Machina (August 2024) and dottxt (August 2024). The most recent entry is a Stack AI Series A, dated May 2026 on Crunchbase's activity feed. He usually appears in rounds alongside other investors and has not been listed as lead on any of them.
Crunchbase attributes 17 AI investments since 2023 to him. The portfolio named there includes Dash Bio, Unsloth AI, Superlinked, LlamaIndex, Unify, dottxt, P-1 AI, Stack AI, Lleverage, Cartesia, cognee inc and kapa.ai. Other companies on his Crunchbase list include GlassFlow, Trace Machina, Polars and Unstructured Technologies (Series A).
Lleverage, a Dutch AI software services company, raised a €2 million pre-seed round that included him alongside Martijn Niessen and Chris Moojen, according to Nordic9. Most of his AI backing sits close to his own field of AI infrastructure, data and tooling for developers.
Third-party databases describe his stage focus as pre-seed, seed and angel. Crunchbase also shows him in Series A rounds such as Polars, Stack AI and Unstructured. Fundable tags his activity as artificial intelligence, software, natural language processing and web development. Tracxn lists enterprise applications and high tech among his top sectors, and says his investments span the United States, Germany and several other countries.
He has not published a check size, a fund size or a formal investment thesis that we could find. Founders should not assume a typical ticket. His public posts and talks focus on open source, AI infrastructure and building developer-facing products, which matches most of his portfolio. A founder pitching him would be best served by a clear technical story that relates to the AI data and developer stack.
- Cartesia: AI company in his Crunchbase portfolio, with a round dated December 2024.
- LlamaIndex: AI company listed in his Crunchbase AI portfolio.
- Unsloth AI: AI startup listed in his Crunchbase AI portfolio.
- dottxt: AI startup he invested in, with a round dated August 2024.
- Dash Bio: AI-focused startup, with a round dated October 2024.
- P-1 AI: seed round dated April 2025.
- Stack AI: Series A, shown as his latest investment on Crunchbase (May 2026).
- Superlinked: AI startup listed in his Crunchbase AI portfolio.
- Unify: AI startup listed in his Crunchbase AI portfolio.
- Lleverage: Dutch AI software services company that raised a €2 million pre-seed round with him as an investor.
- cognee inc: AI startup in his Crunchbase portfolio, with a seed round listed.
- Polars: Series A dated September 2025 on Crunchbase.
- kapa.ai: AI startup listed in his Crunchbase AI portfolio.
- en.wikipedia.org/wiki/Bob_van_Luijt
- crunchbase.com/person/bob-van-luijt-cfb7
- crunchbase.com/person/bob-van-luijt-cfb7/person_overview_investor/time
- devblogs.microsoft.com/agent-framework/revolutionizing-ai-search-with-
- datasciencedojo.com/speaker-bob-luijt
- innmind.com/downloads/ai-angel-investors-database
- tracxn.com/d/people/bob-van-luijt/__HX4a4TQ8Cpk3MryFcO0UjTHpHc36eW6oLA
- nordic9.com/news/lleverage-in-2-million-in-pre-seed-funding-with-dutch
AI portfolio
Investing activity
Bob van Luijt has made 24 investments according to Crunchbase. 17 of those investments since 2023 were in AI companies, including Dash Bio, Unsloth AI, Superlinked, LlamaIndex and Unify.
Deals
Frequently asked questions about Bob van Luijt
Who is Bob van Luijt?
He is a Dutch entrepreneur and angel investor based in Amsterdam. He co-founded Weaviate, an open-source vector database, and serves as its CEO.
What stage does Bob van Luijt invest in?
Third-party databases list pre-seed, seed and angel as his stage focus. Crunchbase also shows him in Series A rounds, including Polars and Stack AI.
What is Bob van Luijt's typical check size?
No check size has been published by him or in sources we found, so we do not state one. Founders can ask him directly.
Which AI startups has Bob van Luijt invested in?
Crunchbase lists Dash Bio, Unsloth AI, Superlinked, LlamaIndex, Unify, dottxt, P-1 AI, Stack AI, Lleverage, Cartesia, cognee inc and kapa.ai among his AI investments.
Does Bob van Luijt lead rounds?
Crunchbase shows no lead investments for him. He usually appears as one of several investors in a round.
How can founders contact Bob van Luijt?
He is on LinkedIn at linkedin.com/in/bobvanluijt and on X as @bobvanluijt. His personal site is txt.vanluijt.nl. He has not published a pitch process.
Is Bob van Luijt an angel investor?
Yes. Bob van Luijt invests personally as an angel. Crunchbase counts 24 investments.
What AI companies has Bob van Luijt invested in?
Bob van Luijt's AI investments include Dash Bio, Unsloth AI, Superlinked, LlamaIndex, Unify, dottxt, P-1 AI and Stack AI.
Where is Bob van Luijt based?
Bob van Luijt is based in Amsterdam, The Netherlands.
How can founders reach Bob van Luijt?
Founders on Lounge can see Bob van Luijt's contact details in AI Investor Contacts (paid plans), check for a warm introduction through members who worked with them under Warm Paths, and add Bob van Luijt to their Investor Pipeline to track the conversation.