Sep 18, 2026

My favorite open source software that I use every day

1. Excalidraw (by @Vjeux):

I do all my planning, tracking, and notes here.

Super useful.

I self-host it and have my own custom hotkeys and modifications, and I built a CLI for my agents to use for it.

Excalidraw workspace showing custom diagrams and notes — Excalidraw — planning, tracking, and notes

2. OpenWhispr (by @gabrielste1n):

Stop paying for closed-source transcription tools that you can't modify yourself.

Build your own custom solution that your agents can mod off of OpenWhispr.

I've got my own setup that lets me navigate my computer fully with my mouse and voice, and I'm working on adding my own trigger words to execute certain actions, like opening X.

OpenWhispr open-source transcription tool interface — OpenWhispr — local speech-to-text and agent integration

3. T3 Code (by @theo and friends):

I don't use this every single day, mostly just when I hit my Codex limit or want to test a model outside of Codex.

But for developers, it's by far the best interface; I'm just missing a few things from Codex to fully switch.

T3 Code editor interface — T3 Code — web-first agentic coding interface

4. The Codex harness:

While the Codex app isn't open source, the Codex harness is, and with Codex as my daily driver, I don't know what I would do without it.

Codex harness architecture diagram and code structure — Codex harness — extensible open agent infrastructure

5. Android:

My phone is Android, and I like it that way.

Codex can go install apps over there and control my device over ADB without me having to get a license or have Apple double-check everything I'm doing every week.

Android device control over ADB — Android — agent automation and control over ADB