PrincipalAI

Know what your codebase is made of (@FileCityAI)
Live commits, all repos (Activity Feed)
Know if it's what you intended (story-based monitoring)

[Yohei @yoheinakajima]

@Replit narrative walkthrough video of repo for anyone interested: https://t.co/kDPiYRAbdm

[FileCity @FileCityAI]

FileCity Tour: stainful

An open-source Stainless alternative. Generate idiomatic, fully-typed Python SDKs from OpenAPI specs + stainless.yml configs. Runs locally with auto-pagination, retries, typed errors, streaming, sync/async — zero migration, no SaaS.

https://t.co/ofsMrgQEHj

[FileCity @FileCityAI]

New ways to use file cities to build mental models of software ownership

[FileCity @FileCityAI]

File City secured a sweet product placement in The Devil Wears Prada 2. Money well spent 😆

[Fernando @Principal_ADE]

Prototyping New Code Review

[FileCity @FileCityAI]

FileCity Tour: opencomputer

A secure persistent cloud VMs for AI agents. Full Linux machines (not containers) that hibernate when idle, keep state across sessions, support checkpoints, preview URLs, and run agent loops directly inside the VM.

https://t.co/dPs6BU0dI8

[FileCity @FileCityAI]

FileCity Tour: openpilot

An open-source operating system for robotics that upgrades driver assistance on 300+ car models into advanced self-driving capabilities.

https://t.co/FjiMnU8BKv

[PrincipalAI @Principal_AI_]

@Dhanush_Nehru

[FileCity @FileCityAI]

Excited to watch this project grow with commits and new contributors showing up in the activity feed in real time.

[PrincipalAI @Principal_AI_]

@yeabu369 We explored using height as a marker for size, but keeping it simple for now.

[PrincipalAI @Principal_AI_]

@DamiDina @FileCityAI We will soon 🤓

[PrincipalAI @Principal_AI_]

Every change, every file. Agents and humans, one view. That's @FileCityAI . Open Principal AI in the morning and it's already there, along with the Activity Feed.
But that's just what you see. The real question is whether your agents did what you intended. That's story-based monitoring. We're defining the category.

[PrincipalAI @Principal_AI_]

@Mia_ai_fandom @garrytan Agreed. We think OTEL accessibility is going to be the deciding factor. The Activity Feed is just the visibility layer. The production part is story-based monitoring inside Principal AI. Visible observability as part of development, not bolted on

[PrincipalAI @Principal_AI_]

@gork @LukaMagic1236 @garrytan We'll take "open-source development real-time monitoring powerhouse."
Thanks @grok.

[PrincipalAI @Principal_AI_]

@grok @hungxun254458 @garrytan Principal AI shows you what's happening inside any codebase, live. Every commit, every change, who made it and when. Free at https://t.co/smax2psyJo

[FileCity @FileCityAI]

@TigerBeetleDB Made you a File City Tour of tigerbeetle

A visual map + narrated walkthrough of the financial transactions database for high-throughput processing.

https://t.co/HJBR5QGjNt

Great work! @TigerBeetleDB @jorandirkgreef

[FileCity @FileCityAI]

@RoundtableSpace Made a File City Tour of agency-agents

A visual map + narrated walkthrough of the complete AI agency with specialized agents, processes, and deliverables.

https://t.co/3556lnhv3X

[PrincipalAI @Principal_AI_]

New album cover just dropped 🔥 @hf0

[Fernando @Principal_ADE]

Getting our applications out there @hf0

[PrincipalAI @Principal_AI_]

175 bytes per log. 68 bytes as an event. Now multiply that difference across every request your system handles. Fernando nailed this.

[Fernando @Principal_ADE]

Making some graphics to start an observability discussion. This log line is 175 bytes. It gets written millions of times a day. Every time, the only thing that changes is 4 variables.
Why are you storing the other 107 bytes over and over?