Bjarne Christiansen
FounderFounder at Realm
San Francisco, California
Writes $5K – $25K checks · typically $15K
FoundedRealm · YC
About
Bjarne Christiansen is an engineering leader with over 25 years of experience across AI/ML, IoT, and real-time data processing, currently working as a fractional CTO and product owner. He co-founded Realm, where he helped build the realm-core C++ storage engine, which was later acquired by MongoDB, and has since built industrial AI condition-monitoring at Cohera and led agentic AI architecture at Float. Based in Copenhagen, he has scaled engineering organizations across 13 countries and worked in regulated environments including pharma (GMP/21 CFR Part 11) and energy grid systems.
Founder at RealmYC S11
Intro paths
Bjarne went through Y Combinator (Summer 2011) — any YC alum in your network can reach them through the YC community.
In turn, Bjarne can intro founders to Realm's investors below.
Realm's investors · 3
Co-founders at Realm
Experience
- Fractional CTO / Product OwnerFractional CTO / Product Owner | Various Companiescurrent2023 — presentSan Francisco Bay Area
- Various StartupsFounder, Board Member, and Strategic Advisorcurrent2016 — presentSan Francisco Bay Area
- FloatChief Technology Officer2025 — 2026Copenhagen
- Stealth ModeCo-founder & CTO2025Copenhagen, Capital Region of Denmark, Denmark
- GoodwingsInterim Chief Technology & Experience Officer (CTO/CXO)2025Copenhagen, Capital Region of Denmark, Denmark
- Cohera IncFounder & CEO2019 — 2025San Francisco Bay Area
- RealmCo-founder2011 — 2018San Francisco Bay Area
- NokiaSCM Product Owner1999 — 2012Copenhagen, Capital Region, Denmark
- Freelance (Self employed)Web Designer & Consultant Software Developer1994 — 2011Copenhagen, Capital Region, Denmark
Skills & more
+12 more
Sales OperationsSystem ArchitectureStart-upsBusiness DevelopmentGlobal Cross-Functional Team LeadershipProject ManagementVenture CapitalDistributed SystemsSoftware EngineeringAgile MethodologiesSoftware DesignSoftware DevelopmentLanguages Danish · English
From Bjarne's professional profile.
Network1
Investors connected to Bjarne in public investor directories — a warm-intro map.
Frequently asked questions
- Who is Bjarne Christiansen?
- Bjarne Christiansen is an engineering leader with over 25 years of experience across AI/ML, IoT, and real-time data processing, currently working as a fractional CTO and product owner. He co-founded Realm, where he helped build the realm-core C++ storage engine, which was later acquired by MongoDB, and has since built industrial AI condition-monitoring at Cohera and led agentic AI architecture at Float. Based in Copenhagen, he has scaled engineering organizations across 13 countries and worked in regulated environments including pharma (GMP/21 CFR Part 11) and energy grid systems.
- Where does Bjarne Christiansen work?
- Bjarne Christiansen is Founder of Realm.
- What check size does Bjarne Christiansen write?
- Bjarne Christiansen typically writes checks of $5K – $25K.
- What companies did Bjarne Christiansen found?
- Bjarne Christiansen founded Realm.
- Where did Bjarne Christiansen go to school?
- Bjarne Christiansen studied at Y Combinator (Entrepreneurship, business); Hillerød Business School (Bachelor's degree, International Business); HTX (Higher Technical Examination Programme, Mathematics and Computer Science).
Founder mafias
Y Combinator mafia8,773
Also came through, then founded or led a company.
+ 8,766 more
Y Combinator mafia4,716
Also came through, then founded or led a company.
+ 4,709 more
Same school
Also attended Y Combinator2,000
+ 1,994 more
Also attended HTX1
Shared employers
Also worked at Stealth Mode17
+ 11 more
Also worked at Nokia179
+ 173 more
Also worked at Freelance (Self employed)14
+ 8 more
















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