# Effy Zhang (slim)

> Effy Zhang is former founder and CEO (May 2023–September 2024); now Anthropic MTS. Baserun on Anchor Terminal, with grades, an about and public profiles.

- Full: https://www.anchorterminal.com/people/effy-zhang/index.md (~750 tokens) · this version ~530 tokens · JSON https://www.anchorterminal.com/people/effy-zhang/index.json · canonical https://www.anchorterminal.com/people/effy-zhang/
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-10-27
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

Former founder and CEO (May 2023–September 2024); now Anthropic MTS.

Effy Zhang founded Baserun, a testing and observability platform for LLM applications, in Y Combinator's Summer 2023 batch.

- LinkedIn: https://www.linkedin.com/in/effyz
- X: https://x.com/effyyzhang

## What Effy builds

- [Baserun](https://www.anchorterminal.com/tools/baserun.md), graded F, 7.3/100, in Agent observability & evals. Discontinued LLM testing and monitoring platform with Python and JavaScript SDKs for tracing model calls. Former founder and CEO (May 2023–September 2024); now Anthropic MTS, researched 2026-10-27.

## Works with

- [Adam Ginzberg](https://www.anchorterminal.com/people/adam-ginzberg/), Former co-founder (May–November 2023); now engineer at Subframe

## Questions

### Who is Effy Zhang?

Effy Zhang founded Baserun, a testing and observability platform for LLM applications, in Y Combinator's Summer 2023 batch.

### What does Baserun make?

Anchor Terminal lists Baserun from Baserun.

### How are Effy's tools graded?

Baserun is graded F, 7.3 out of 100, on Anchor Terminal's benchmark, which scores every listing against the same checklist.

## Sources

- https://www.linkedin.com/in/effyz/details/experience/
- https://www.ycombinator.com/companies/baserun
- https://www.linkedin.com/in/effyz
- https://x.com/effyyzhang
- https://www.linkedin.com/in/adam-ginzberg-77b6ba126/details/experience/
- https://www.linkedin.com/in/adam-ginzberg-77b6ba126
- https://x.com/baserunai
- https://github.com/baserun-ai/baserun-py
- https://github.com/baserun-ai

These are the people building the tools we list, named for their public role in the company or project behind a listing, from public pages, with the date it was researched.