Structured Commits as Lesson Inputs
Commit messages with What/Why/Learned sections capture reusable insights at the moment of discovery, feeding downstream lesson extraction pipelines
Lessons Hub
Browse, search, and query engineering lessons harvested from multiple GitHub repositories. Features full-text search, AI-powered chat with RAG, corpus gap detection, and multi-cloud deployment.
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Client-Side PDF Generation in Serverless
When your serverless backend can't run PDF libraries (no headless Chrome, no native modules), generate the PDF in the browser instead. The server renders an HTML page with the data embedded, and client-side JavaScript builds and downloads the PDF. The user doesn't notice the difference.
Cloudflare D1
D1 is serverless SQLite hosted by Cloudflare. It gives you a real SQL database accessible only from your Worker — no connection strings, no connection pooling, no database server to manage. For small apps, it eliminates the entire database operations layer.
Cloudflare Workers
Cloudflare Workers are serverless JavaScript functions that run at the edge — no server to manage, no container to configure. They wake up on each request, execute, and sleep. For small to medium web apps, they replace traditional backend servers entirely.
Deploying is Not Pushing
In a serverless workflow where `wrangler deploy` pushes code directly to production, deployment is decoupled from git. This means there's no CI/CD pipeline gating production changes — the developer must impose their own discipline. Treat every production deploy like a `git push --force`: require exp...
Dev-Prod Schema Parity
When you add a database column via direct SQL instead of a migration file, your dev environment won't have it. The code works in production (where you ran the SQL) but crashes in dev (where the column doesn't exist). Always use migration files, even for "quick" schema changes.
Echo vs Printf for CLI Secrets
When piping a value to a CLI tool that stores secrets, `echo` adds a trailing newline that becomes part of the stored value. This silently breaks any credential that's compared byte-for-byte — OAuth client IDs, API tokens, webhook secrets. Always use `printf` instead.
Google OAuth2
Google OAuth2 lets users sign in with their Google account. Your server redirects to Google, Google authenticates the user, and redirects back with a code. You exchange the code for the user's email. The entire flow is four HTTP calls and requires no client-side SDK.
OAuth Users Need Onboarding Gates
When users can sign up via OAuth (Google, Apple, etc.), they bypass your signup form — and any required fields on it. If your app requires data that OAuth doesn't provide (a phone number, a company name, a role), you need a gate between login and the main app that collects it before proceeding.
Phone Numbers as Data, Not Identity
When a phone number appears in your product, decide early whether it's an identity (the account itself) or data (a field on a record). Conflating the two creates the wrong data model, the wrong auth flow, and forces users into a single-phone-per-account constraint that doesn't match reality.