Jean Sini
InvestorVenture Partner at Partech Ventures
New York, New York
Writes $100K – $12M checks · typically $8M
Find your path to Jean
685 people in our graph share verified history with Jean — schools, employers, funds. One of them is your warm intro.
Javier SolterounlockedJean: together at Canva (2022–2024)
Jean: together at Canva
×3Jean: together at Treasure
×2Jean: together at Cadre
About
Jean Sini is the founder and managing partner of Irregular Expressions, where he invests in technical founders at pre-seed and seed stages in data, infrastructure, security AI, and developer tools. He has over two decades of experience building and scaling startups as a co-founder while leading engineering teams, and has been advising and investing in founders since 2012. He has focused full-time on investing in infrastructure software since 2018.
Contact· published on Jean's own website
Experience
- Irregular ExpressionsFounder + Managing Partnercurrent2018 — presentNew York, New York, United States
- CanvaInvestor + Advisorcurrent2012 — presentGreater Sydney Area
- People.aiInvestor + Advisorcurrent2016 — presentSan Francisco Bay Area
- Antheia, Inc.Investorcurrent2015 — presentSan Francisco Bay Area
- PartechVenture Partnercurrent2025 — presentNew York, New York, United States
- PartechGeneral Partner2019 — 2025New York, New York, United States
- ProdPerfectInvestorcurrent2018 — presentNew York City Metropolitan Area
- KickpayInvestor + Advisor2014 — 2023San Francisco Bay Area
- MindKick Inc.Investor2017 — 2022San Francisco
- First Round CapitalAngel Track2018 — 2019New York City Metropolitan Area
- Grove (acquired by Wealthfront)Investor + Advisor2016 — 2019San Francisco Bay Area
- Treasure Data, Inc.Investor + Advisor2012 — 2018San Francisco Bay Area
- CadreChief Technology Officer2016 — 2018New York City Metropolitan Area
- Leap LifeAdvisor2016 — 2018San Francisco Bay Area
- BoxbeeInvestor2012 — 2018San Francisco Bay Area
- FountainCo-founder + Chief Technology Officer2013 — 2016San Francisco Bay Area
- One Kings LaneChief Product + Technology Officer2012 — 2013San Francisco Bay Area
- FieldwireAdvisor2011 — 2013San Francisco Bay Area
- IntuitDirector, Software Engineering2009 — 2012Mountain View, California
- IntuitVice President, Data Aggregation2009 — 2012Mountain View, California
- Twelvefold MediaChief Technology Officer2008 — 2009San Francisco Bay Area
- ActiveweaveCo-founder + Chief Technology Officer2005 — 2008San Francisco Bay Area
Skills & more
Venture CapitalStart-ups89Entrepreneurship68Fundraising14Product Strategy6Strategy28Leadership18Software Engineering39Product Development8Software Project Management15Product Management40Distributed Systems42
+8 more
ScalabilityArchitectureMobile ApplicationsMobile DevicesEnterprise SoftwareSoftware DevelopmentUser ExperienceUser Experience DesignLanguages English · French
From Jean's professional profile.
Investments
Per curated public sources.
Colleagues at Partech Ventures
Alexandra Eychenne
Compliance & Risk Officer at Partech Ventures
Alexandre Durrive
Chief Technology Officer at Partech Ventures
Alexis Lancien
Senior Associate at Partech Ventures
Alison Imbert
Partner at Partech Ventures
Andrew Whiting
Partner at Partech Ventures
Ariadne Lemieux-Cumberlege
Senior Associate at Partech Ventures
Arnaud De Keulenaer
Senior Legal Counsel at Partech Ventures
Arnaud Minvielle
General Partner at Partech Ventures
Frequently asked questions
- Who is Jean Sini?
- Jean Sini is the founder and managing partner of Irregular Expressions, where he invests in technical founders at pre-seed and seed stages in data, infrastructure, security AI, and developer tools. He has over two decades of experience building and scaling startups as a co-founder while leading engineering teams, and has been advising and investing in founders since 2012. He has focused full-time on investing in infrastructure software since 2018.
- Where does Jean Sini work?
- Jean Sini is Venture Partner at Partech Ventures.
- What check size does Jean Sini write?
- Jean Sini typically writes checks of $100K – $12M.
- What companies has Jean Sini invested in?
- Investments tracked here include Actual AI, Airfold, Alectio, Antheia, Architect.io, Canva, Medigate, Medigate by Claroty, Memfault, Modiqo, Objective.
- Where did Jean Sini go to school?
- Jean Sini studied at Télécom Paris (MS, Computer Science); Pierre and Marie Curie University (DEA, Computer Systems, Distributed Computing).
Founder mafias
Intuit® mafia82
Also came through, then founded or led a company.
Val AgostinoDirector of ProductFounded Monarch +2Sriharsha KaramchatiSoftware EngineerFounded Questbook +2Paul EnglishVP of TechnologyFounded Moonbeam +2Adam JacksonSenior Product Development ManagerFounded Doctor on Demand +1Bryant ChouSenior Software EngineerFounded Ploy +1Nissim TapiroDirector of engineeringFounded Nextinsurance +1
+ 75 more
Pierre and Marie Curie University mafia49
Also came through, then founded or led a company.
Guillaume LampleDoctor of Philosophy - PhDFounded Mistral AIThomas WolfPhDFounded Hugging FaceAnne OsdoitDIU CESAM - Centre d'Etudes Statistiques Appliquées à la MédecineFounded Moon Surgical +2Ben SaundersPhDFounded One Biosciences +2Maxime AllouchM.S. in Applied Maths & Artificial Intelligence (M2A)Founded Verahealth +1Jeff ClavierDiplome d'Etudes ApprofondiesFounded Uncork Capital
+ 42 more
Télécom Paris mafia46
Also came through, then founded or led a company.
Arthur MenschMaster of ScienceFounded Mistral AIKarim BoustaBachelor of Science (BSc)Founded Tactix +2Henri MoissinacPhDFounded TIER Mobility +1Philippe LavalMasterFounded SINEQUA +1Tancrede CollardFounded QuestDB +1Felix GerlachShortterm Exchange ProgrammeFounded Passbase +1
+ 39 more
First Round Capital mafia33
Also came through, then founded or led a company.
DeVaris BrownAngel Track InvestorFounded Super Heroic +2Bill TrenchardPartnerFounded LiveOps +1David J. PhillipsAngel TrackFounded Fondo +1Stephen CarrollSpecial Project InternFounded Findigs +1Auston BunsenSenior Software EngineerFounded Accessgrid +1Matt SacksFinance / Valuation InternFounded Luminary Media
+ 26 more
People.ai mafia6
Also came through, then founded or led a company.
Same school
Also attended Télécom Paris98
Arthur MenschCo-founder & CEO of Mistral AIRania BelkahiaInvestor at EQT VenturesLukas WeberPartner, CEO at Verve VenturesCyril CollonGeneral Partner at Partech VenturesJulien-David NitlechManaging Partner at Iris CapitalJonathan DenaisInvestment Director at Educapital
+ 92 more
Also attended Pierre and Marie Curie University100
Guillaume LampleCo-founder & Chief Scientist of Mistral AIThomas WolfCo-founder & Chief Science Officer of Hugging FaceJeff ClavierFounding Partner at Uncork CapitalDimitri KrempPrincipal at Axeleo CapitalJack GuedjInvestor at Sand Hill AngelsOphélie LaurinInvestment Associate at World Fund
+ 94 more
Shared employers
Also worked at People.ai12
Jeff RichardsInvestor at GGV CapitalIhar MahaniokFounder & General Partner at Geek VenturesNakul MandanFounder of Audacious Ventures, an early stage VC firm partnering with ambitious technology foundersRon HirsonVenture Partner at Founders Circle CapitalOleg RogynskyyStrategic Advisor at DniproJonathan JaffeSecurity Advisor at Modern Technical
+ 6 more
Also worked at Antheia, Inc.7
Jeff KarrasGeneral Partner at America's Frontier FundKristy HawkinsCo-Founder & CSO at Antheia, Inc.Eric d'EsparbesChief Financial Officer at Antheia, Inc.Zack McGaheyChief Operating Officer at Antheia, Inc.Heidi PucelChief People Officer at Antheia, Inc.Aaron CravensExecutive Officer at Revel Pharmaceuticals
+ 1 more
