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Mirrors launch: what they're building and where to launch next

What they're building

Catch and fix AI agent regressions before they reach production

Batch
Y Combinator Fall 2026
Industry
B2B
Team size
2
Based
San Francisco, CA, USA

Founders

runmirrors.com ↗

See their funding details ↗

Mirrors on the record

What they shipped

  • From its YC profile: Mirrors provides regression testing for AI agents. Teams shipping agents constantly change prompts, models, and tools, and there's no way to test any of it. Agents call bespoke internal tools and APIs no test framework can reproduce, so most teams ship on vibes. Mirrors rebuilds the tools your agent calls from your own production traces, then replays real sessions against every change before it merges. You see which tool calls changed, which arguments moved, and where state landed differently. And when something fails, we tell you whether your agent regressed or something upstream moved. (source)
  • Its own site describes it as: "Mirrors builds a runnable twin of the systems your AI agents call from their traces, then replays real sessions against every prompt, tool or model change." (source)

Who is behind it

  • Aryan Singhal, Founder/CEO: Co-Founder & CEO @ Mirrors (YC F26). Published 6 AI/ML research papers in high school (3 at NeurIPS). Prev. ML research @ UT Austin, UCSB. (source)

Timeline

  1. 2026: founded, per its YC profile. (source)
  2. 2026-07-29: "Show HN: Mirrors – Improve AI agents with staging environments" posted to Hacker News by idyeetya, 4 points and 0 comments. (source)

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Where else to launch Mirrors

  • Product Hunt ↗
    Self-promotion allowedFree
  • Hacker News (Show HN) ↗
    Self-promotion allowed, within the community's rules
    Audience: Hacker News readers; engineers, technical founders, infra-curious people
  • Indie Hackers Forum ↗
    Self-promotion allowed
    Audience: IndieHackers; bootstrapped solo founders sharing revenue and behind-the-scenes
  • Demand Curve ↗
    Self-promotion allowed, within the community's rules
    Audience: Slack community; tight-knit, pseudo-private peer group
  • Dev Hunt ↗
    Self-promotion allowedFree
  • No Code Founders ↗
    Self-promotion allowed, within the community's rules
    Audience: Slack community; tight-knit, pseudo-private peer group
  • OnlineGeniuses ↗
    Self-promotion allowed, within the community's rules
    Audience: Slack community; tight-knit, pseudo-private peer group
  • Product Makers ↗
    Self-promotion allowed, within the community's rules
    Audience: Slack community; tight-knit, pseudo-private peer group

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