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Open source background agents

37 starsTypeScript

Mistle – Open-source infrastructure for running sandboxed coding agents

by jonathanlowhy·May 13, 2026·6 points·0 comments
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AI Analysis

●●SolidShip ItBig Brain

Credential proxying keeps keys out of sandboxes, unlike Ramp Inspect.

Strengths
  • •Explicit config model avoids magic, letting you bring your own keys and models.
  • •Snapshot feature captures prepared environments for instant session startup.
  • •Identity attribution links agent work back to specific human users.
Weaknesses
  • •Not accepting contributions yet limits community growth and extension.
  • •Early stage bugs expected, and remote providers like E2B add complexity.
Target Audience

Engineering teams building internal AI agent workflows

Similar To

Ramp Inspect · Stripe Minions · E2B

Post Description

Hi HN, I'm Jonathan. My co-founder, Thomas, and I started building Mistle in Feb.

We saw larger tech companies like Ramp (Inspect) and Stripe (Minions) build this internally and thought an open source version should exist.

We made a few very intentional decisions when working on this:

1. Credentials are kept out of the sandbox. Authorized access goes through a proxy, so agents do not directly receive credentials.

2. The harness is not our problem. We're not going to tackle things like memory, self-learning.

3. No magic. Configurations are explicit. You can bring your own keys for models, sandboxes, and other providers. You can write your own instructions and agent.

Mistle can be run locally with a single command: https://github.com/mistlehq/mistle#run-mistle-locally

Questions, feedback and ideas are welcome!

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