Cra.mr

Junior is the open-source Slack agent I've been building at Sentry for the last four months.

Search and execute primitives are how MCP gets useful at scale.

We found 100+ vulnerabilities with Warden across Sentry and a few big OSS repos—here’s how we scope skills, iterate locally, and run it on PRs.

I keep ending up in the same place: distributed tracing sounds great, but the instrumentation is a mess, the cost is obscene, and most of what I actually want is structured logs with a trace_id attached.

There is a lot of bad discourse around whether we should optimize content for agents at all, and most of it misses the point.

I built a Slack bot called Junior using Vercel's Chat SDK, Pi, AI Gateway, and Sandboxes.

We found 8 real security vulnerabilities in Sentry that our pen testers and bug bounty program missed.

I shipped Warden - a Fair Source project that lets you run code review agents locally and on pull requests.

The MCP vs CLI debate is missing the point.

If you're not caught up on the current hypewave, coding agents like Claude Code and Cursor have latched onto skills recently.

I've spent a fair bit of time explaining why the GitHub MCP server design is wrong.

An experiment wrapping Sentry's MCP in a subagent to cut token costs by 95%, with benchmarks showing the trade-offs between context efficiency and response time.

Hackweek at Sentry this year was exactly as you'd expect: LLMs everywhere.

I spent two months forcing an unnatural constraint on myself: what if I could only rely on agents writing code for a real-world production service?

So you're on the MCP hype train, eh?

Something's been bothering me lately surrounding the conversation of MCP servers.

Like a lot of my fellow nerds (and maybe all of humankind), I was blessed with shitty vision from childhood.

I have been fiddling with an MCP server for Sentry over the last few weeks.

One of the most difficult challenges I've faced in my career is figuring out product-market fit.

Open Source software takes time and money to develop, and that time and money has to come from somewhere.

Earlier this week I was at a dinner with a number of founders where the conversation focused on brand, visual design, and in general a lot of the components that make up your early stage marketing strategy.

Whether you're starting a company, or you're in a leadership position at another company, you likely need more around focus your approach to hiring.

So you're starting a company and you want an Open Source business model, eh?

I have a challenge.

I've been using React a long time at this point, and it's by far my favorite approach to building a UI - interactive or not.