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MIT 6.7960 L09: Hacker's Guide to Deep Learning — Practical Know-How to Make Nets Actually Obey

Training neural nets is closer to engineering than magic: look at the data, overfit a mini-batch to prove capacity exists, then regularize back the generalization; learning rate is always the highest-leverage knob.

Chrome DevTools MCP: The MCP Server Wired Directly to CDP

chrome-devtools-mcp, maintained by the Chrome team, packages DevTools capability as an MCP server: performance traces and insights, Lighthouse audits, heap snapshots, extension management — none of which @playwright/mcp exposes. It runs on Puppeteer, so interactions auto-wait; the costs are Chrome-only support and usage statistics reported to Google by default.

tech debug

Mobile Chrome Redirects Back to Login After Sign-In: Debugging an HTTP-to-HTTPS Entry Point Issue

When mobile Chrome keeps redirecting back to the login page after sign-in, the culprit isn't always OAuth or broken frontend state. In this case, the root cause was that the HTTP entry point for app-dev.daodao.so wasn't issuing a 301 redirect to HTTPS, so /auth/me requests sent with an http origin didn't include the auth_token cookie.

tech guide

Installing and Verifying Superpowers for GitHub Copilot CLI: Implementation, Diagnostics, and Validation

A hands-on log of installing Superpowers (packaged by DwainTR) for Copilot CLI on a local machine — including the diagnostic process when skills didn't appear after installation, the fix, and practical tips.

tech guide

nginx Restarted Fine, but Cloudflare Keeps Returning 502 — Even Though the Origin Is Healthy

A brief error during nginx restart caused Cloudflare to mark the origin as unhealthy and stop forwarding requests, returning 502 on its own. The key clues: localhost hits to the origin return 200, and nginx access logs are completely empty. Just wait for Cloudflare to automatically re-check the origin — it recovers on its own.

RAG Common Failure Modes: 10 Problems and Their Solutions

When a RAG system breaks, 90% of the time it's one of these 10 failure modes. Identify which one first, then apply the matching fix — far more effective than optimizing blindly.

RAG Observability: Per-Node Tracing to Turn the Black Box Transparent

The hardest part of a RAG system isn't building it — it's figuring out why a particular answer went wrong. Pipeline Tracing records every step's decisions and data so debugging has a clear trail to follow.