brenogazzola

# Rails + PostgreSQL Performance Audit Playbook

A field-tested method for finding what's actually burning your database CPU, built for a
Rails monolith on managed PostgreSQL (Cloud SQL / RDS / etc.). It assumes no APM — just
`pg_stat_statements`, `pg_stat_activity`, and discipline. It pairs well with an LLM: point
one at this file plus your query results and let it do the attribution; the queries below
are ordered so a human can run them and paste results back.

## The core idea

alexleekt

Hermes Agent — Dedicated Machine / VM Setup Guide

A complete, opinionated plan for setting up a fresh machine (physical or virtual) whose sole job is running the Hermes AI agent reliably 24/7.

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1. Operating System Recommendation

Environment	Recommended OS	Notes

Tostino

Making Postgres materialized view refreshes O(delta) instead of O(total)

Many developers assume PostgreSQL materialized views handle incremental updates out of the box. They do not. If you have a materialized view with millions of rows and a single underlying record changes, both native refresh options process the entire dataset.

Because of this limitation, anyone needing immediate maintenance or working with large datasets must abandon materialized views entirely. The standard workaround is to manually maintain a standard table using custom database triggers or application logic.

I've been working on a patch to fix this. It adds an optional WHERE clause to the REFRESH MATERIALIZED VIEW command, letting you scope a refresh to exactly the rows that changed. The patch is currently under review on the pgsql-hackers mailing list.

This approach requires two things. First, the materialized view must have a unique index (the same requirement as REFRESH MATERIALIZED VIEW ... CONCURRENTLY). Second, the

adamamyl

Ah, the joys of waking up to find the Mac's done an overnight upgrade… and erm, suddenly things stop working. Thankfully, me and Claude managed to work out what the fuck is going on… I'm sharing here, as well as having raised in on https://feedbackassistant.apple.com/feedback/22280434 (that seems to need a login?).

Bug Report: macOS 26 breaks /etc/resolver/ supplemental DNS for custom TLDs

Product: macOS 26.3.1 (Darwin 25.3.0, Build 25D771280a) Component: Networking → DNS / mDNSResponder Regression from: macOS 25.x 26.3.0 (working immediately prior to overnight update)

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nateberkopec

Protecting Against Autonomous Agent rm -rf Commands

Protecting Against Agent rm -rf Commands

AI coding agents can run shell commands. Sometimes they run rm -rf by mistake. This deletes files forever. While of course I always read and approve all tool calls manually, by hand, and never let my agents work except under direct supervision 100% of the time, sometimes I miss things.

How It Works

1. Hooks catch rm -rf before it runs
2. Refuse the command with a clear error telling you to use trash

marckohlbrugge

🆕 Update: See more extensive repo here: https://github.com/marckohlbrugge/unofficial-37signals-coding-style-guide

The Unofficial 37signals/DHH Rails Style Guide

About This Document

This style guide was generated by Claude Code through deep analysis of the Fizzy codebase - 37signals' open-source project management tool.

Why Fizzy matters: While 37signals has long advocated for "vanilla Rails" and opinionated software design, their production codebases (Basecamp, HEY, etc.) have historically been closed source. Fizzy changes that. For the first time, developers can study a real 37signals/DHH-style Rails application - not just blog posts and conference talks, but actual production code with all its patterns, trade-offs, and deliberate omissions.

hopsoft

JavaScript Microtasks: A Developer's Guide

What Are Microtasks and Why Should You Care?

As a JavaScript developer, you're likely familiar with the event loop handling asynchronous operations. However, microtasks provide a crucial middle layer between synchronous code execution and the macrotask queue that can significantly impact your application's behavior.

Think of microtasks as high-priority tasks that JavaScript executes immediately after the current synchronous operation, but before the next macrotask (like setTimeout callbacks) or render updates.

Common Sources of Microtasks:

joeldrapper

class FuzzyIndex
  def initialize
    @index = Hash.new { |h, k| h[k] = Set.new }
  end
  
  def []=(key, value)
    trigrams(key).each { @index[it] << [key, value] }
  end
  
  def [](query)

almas

Summary

Notes to install Ubuntu 22.04.4LTS (Upgraded to 24.04LTS) up and running on my 2017 MacBook Pro 15 inch (MacBookPro14,3).

Now everything except the TouchID (Fingerprint), Suspend and Hibernation seems to work for me.

About Ubuntu 24.04LTS: I tried to install Ubuntu 24.04 and didn't have success. There was a crash issue during installation. https://bugs.launchpad.net/subiquity/+bug/2065310 But I installed 22.04 and upgraded it to the 24.04LTS later and it working same as 22.04.4.

Useful References (not mentioned in the text)

AliOsm

KAMAL_REGISTRY_PASSWORD=dckr_pat_xXXxx_x0xXxXx-xX-XXX0xX0x-x
RAILS_MASTER_KEY=00x00xxx000xxx000000xx0x000x0x00
POSTGRES_PASSWORD=xXxxx0xXXx0
MEILI_MASTER_KEY=xXxxx0xXXx0
BLAZER_DATABASE_URL=postgres://service:{POSTGRES_PASSWORD}@service-name-postgres:5432/service_production