Jcode
Jcode is a YC Summer 2026 (S26) company. Based in San Francisco, CA, USA. Team of 1.
About Jcode
Summary
Jcode builds an open-source, terminal-based AI coding agent written in Rust, aimed at software developers who want to run many coding tasks simultaneously. It focuses on the "harness" surrounding the language model: the tools, context, memory, and feedback loops that determine what the model can actually accomplish. Instead of watching a single agent finish a task, developers spin up dozens of parallel sessions, replacing the serial, one-task-at-a-time workflow that characterizes most AI coding tools today.
Business model
A free open-source tier plus paid Enterprise plans.
Go-to-market
Developers adopt Jcode through a one-line terminal install command and the project's open-source GitHub repository; an Enterprise tier is also offered for teams with broader needs.
From the Y Combinator listing
The harness company
An agent is LLM + harness: We work purely on that second component. We do research to produce the most capable harness for coding, and we also make an open source, terminal based, coding agent product with 18k github stars.
Facts
- Consumer / Consumer
- San Francisco, CA, USA
- 1
- Active
- Early
Founders (1)
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