A capable model papers over a vague prompt and you never find out. A cheaper one fails exactly where you were ambiguous. That makes it the better instrument, if you write for it.

mdelapenya.xyz/posts/2026-1...

#AI #codingAgents

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By the way, I lied, it's not 5k ⭐️ yet, only 5 are missing! Who will get the magic number?

github.com/testcontaine...

(3/3)

OFC this number is nothing compared with how any claw or any mid #AI project is doing nowadays, but to me it's a privilege to see a positive trend for a #testing library in the Go ecosystem, where the stdlib comes with almost everything

(2/3)

When I officially joined the #Testcontainers for #Golang project, back in 2022, it had ~1k GitHub ⭐️, and I never thought that it would organically reach 5k ⭐️ in ~4years

(1/3)

Put a coding agent in a microVM and you usually lose your editor and your harness. Not with a @docker.com Sandbox: it answers as an SSH host, so VS Code, Cursor and @t3.gg's T3Code connect unchanged.

Post 3 of Understanding Docker Sandboxes: mdelapenya.xyz/posts/2026-0...

#sbx #codingAgents

A Dockerfile says everything about the inside of an image and nothing about what it may reach. For an agent, that second half is the whole problem.

Docker Sandboxes Kits put the answer in the image itself, as one typed list. Post 2 of my #sbx series:

mdelapenya.xyz/posts/2026-0...

You have to be right every time. Agents only need to be right once. So "please be careful" is not a control. The boundary has to be somewhere the agent can't reach.

My ContainerDays talk on @docker.com Sandboxes, as a post (drawings by @shelajev.bsky.social ):

mdelapenya.xyz/posts/2026-0...

#sbx

3 AI coding agents. 1 Java project. Everyone assumes that's chaos. @mdelapenya.bsky.social says otherwise. We put it to the test live, Thu Sep 17, 8pm CEST. youtube.com/watch?v=9-Wx...

Ryuk is the container starts before any of yours, and it deletes your Docker resources when your test process dies.

I wrote about it in my last post: mdelapenya.xyz/posts/2026-0..., written as a guest post for @jespino.bsky.social internals-for-interns.com blog

#golang #testcontainers #docker

New guest post: my friend @mdelapenya.bsky.social write about Ryuk.

→ your tests hold a TCP connection open to it
→ it drops, 10s grace, then Ryuk deletes everything tagged with your session ID

Check the blog post here: internals-for-interns.com/posts/testco...

#golang #testing #docker

A couple of months ago, I wrote a whole post about choosing the best terminal for agentic development. But I do not work in a terminal anymore.

With @t3.gg's T3Codes agents run on four machines and I steer them from my phone. The work left my desk.

mdelapenya.xyz/posts/2026-0...

#AI #codingAgents