About
Joseph Tso is a computer science graduate from Princeton and co-founder of Haladir.
Founder at HaladirYC W26
Intro paths
YC
Joseph went through Y Combinator (Winter 2026) — any YC alum in your network can reach them through the YC community.
GP
Their group partner at YC was Diana Hu, General Partner at Y Combinator — the partner who ran Haladir's batch and knows the company first-hand. YC profile ↗
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In turn, Joseph can intro founders to Haladir's investors below.
Haladir's investors · 6
Co-founders at Haladir
Experience
- Haladir (YC W26)Co-Foundercurrent2025 — presentSan Francisco, California, United States
- KnotIntern2025New York City Metropolitan Area
- George Mason UniversityResearcher2022 — 2025Fairfax County, Virginia, United States
Frequently asked questions
- Who is Joseph Tso?
- Joseph Tso is a computer science graduate from Princeton and co-founder of Haladir.
- Where does Joseph Tso work?
- Joseph Tso is Founder of Haladir.
- What companies did Joseph Tso found?
- Joseph Tso founded Haladir.
- Where did Joseph Tso go to school?
- Joseph Tso studied at Princeton University.
Founder mafias
Y Combinator mafia8,773
Also came through, then founded or led a company.
Sam AltmanPresidentFounded Tools for Humanity +3Jessica LivingstonCo-founderFounded Y CombinatorAlexis OhanianYC Summer 2005Founded RedditFred EhrsamYC Summer 2012Founded Nudge +1Matt HuangYC Winter 2011Founded HotspotsTrae StephensYC Winter 2022Founded Pursuit +1
+ 8,766 more
Princeton University mafia160
Also came through, then founded or led a company.
Ryan SheaBSEFounded StacksDario AmodeiPhDFounded AnthropicFei-Fei LiBachelor of Arts - BAFounded World LabsChristian SchadeBachelor of Arts - BAFounded Halda Therapeutics +2Emin Gun SirerB.S.E.Founded Avalanche +2Luke EvninBachelor’s DegreeFounded Mpmcapital +1
+ 153 more
Same school
Also attended Princeton University582
Fabrice GrindaCo-founder & Managing Partner at FJ LabsRyan SheaCo-founder of Blockstack (Stacks)Dario AmodeiCo-founder & CEO of AnthropicFei-Fei LiCo-founder & CEO of World Labs; Sequoia Professor of Computer Science at StanfordAndrewAdvisor at Clear VenturesChristal NgAssociate at Golden Gate Ventures
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+ 576 more
Shared employers
Also worked at Haladir (YC W26)3
Also worked at Knot1
Also worked at George Mason University15
Veronica DaiglePresident, National Security Practice at Red Cell IncubationKurt SchererManaging Director at C5 CapitalMikhail ZeldovichAdvisor at Cento VenturesDhruv BansalInvestor at VMG PartnersGillian KrugProgram Manager at Conscious Venture LabLawrence GreenbergVenture Partner at Motley Fool Ventures
+ 9 more