Sylvian

YC F25 · Inactive · Specialized AI Agents.

Competitors

Companies closest to Sylvian
Company	Category	Status	Program
KairosShared: reinforcement learning, specialized, agentActiveAI, Devtools	AI, Devtools	Active	YCX25
Smallest.ainot in a program hereShared: specialized, agentElsewhereOther	Other	Elsewhere

Adjacent

Companies next to Sylvian
Company	Category	Status	Program
ThetaShared: reinforcement learning, specializedActiveAI	AI	Active	YCX25
FreesoloShared: reinforcement learning, specializedActiveAI, Devtools	AI, Devtools	Active	YCX25
MagmaShared: reinforcement learning, agentActiveAI, Data, Devtools	AI, Data, Devtools	Active	YCS26
Ooak DataShared: reinforcement learning, agentActiveAI	AI	Active	YCS26
Vibrant LabsShared: reinforcement learning, agentActiveAI, Devtools	AI, Devtools	Active	YCW24

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All of F25

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hillclimbTraining Data for Recursive Self-ImprovementActiveAI, Devtools	AI, Devtools	Active
AbsurdThe Creative OS for AI videoActiveAI	AI	Active
AirCapsThe AI copilot for in-person conversations.ActiveAI	AI	Active
AlderAI employees for finance, starting with accounts receivable.ActiveAI	AI	Active
Aleph LabAI language buddy in the games kids loveActiveAI	AI	Active

Founders

William HuangFounder
Niall KehoeFounder

About Sylvian

Sylvian helps companies build specialized AI agents.

YC batch: F25 · Fall 2025
Status, per YC: Inactive
Category: AI
Team size: 2
Location: San Francisco, CA, USA
Founded: 2025
Checked: 1h ago

YC tags: Reinforcement Learning, B2B, AI

Sylvian in F25: 146 companies, 89% AI

GitHub LinkedIn

Sylvian: questions

Which YC batch was Sylvian in?

Sylvian was in Y Combinator's Fall 2025 batch (F25).

Is Sylvian still active?

Y Combinator lists Sylvian as inactive.

Who founded Sylvian?

Sylvian's founders, as listed on its YC page: William Huang (Founder), Niall Kehoe (Founder).

Where is Sylvian based?

Sylvian lists San Francisco, CA, USA as its location on YC's directory.

Sources: each program's public company list, read twice a week. Not affiliated with Y Combinator or any other program. Logos via logo.dev; trademarks belong to their owners.