CI/CD
A large codebase accumulates tests the same way it accumulates technical debt — gradually, then suddenly. A test suite that took 3 minutes a year ago now takes 25 minutes, and nobody can pinpoint when it crossed the threshold from "fast enough" to "everyone waits for CI."
Testing
PySpark code is hard to test because most engineers treat Spark jobs as scripts — a chain of transformations from input to output with no unit boundaries. The result is code where bugs only surface when you run the full job against real data, which takes 20 minutes and costs money.
PWA Testing
Push notifications are one of the most impactful PWA features — and one of the most painful to test. They involve permission APIs, service worker push event handlers, Web Push Protocol, notification click handling, and platform-specific rendering quirks. Getting them wrong means users miss critical updates or, worse, get spammed
Testing
Getting your browser extension rejected from the Chrome Web Store is painful. Google's review can take days to weeks. If your extension gets rejected for a fixable issue — a permissions problem, a policy violation, or a content security issue — you're back to the end of the
PWA Testing
A PWA that loads slowly or scores poorly on Core Web Vitals fails to deliver on the promise of an app-like experience. Lighthouse is the standard tool for PWA auditing, but running it manually isn't enough — you need automated performance testing in CI, regression detection, and monitoring
PWA Testing
Offline mode is one of the defining features of a Progressive Web App. Users expect apps to work — or at least degrade gracefully — when connectivity drops. Testing this is harder than it sounds: offline behavior involves service workers, caches, IndexedDB, background sync, and UI state machines that all have to
Testing
CSS regressions are invisible to unit tests and integration tests. A button becomes 2px too small. A card's padding collapses on a specific breakpoint. A dark mode color turns slightly wrong. These are real bugs that reach production because no test caught them — there was nothing to assert
PWA Testing
PWA installability — the ability to add your web app to the home screen and run it as a standalone app — is one of the most visible PWA features. It's also surprisingly easy to break. A missing icon size, a misconfigured manifest property, or a service worker scope issue
Testing
A misconfigured S3 bucket. An RDS instance without encryption. A security group open to 0.0.0.0/0. These are the infrastructure mistakes that make headlines. Policy-as-code tools like Checkov and Terrascan catch them at write time — before terraform apply ever runs. This guide explains how both
Puppeteer
Puppeteer and Playwright share a common origin — most of Playwright's founding team came from the Puppeteer project at Google. They look similar at first glance, but they've diverged significantly. Choosing the wrong one adds friction to your testing workflow. This is a practical comparison covering what
Puppeteer
Puppeteer's network interception capabilities turn browser automation into an API testing tool. You can intercept requests, inspect payloads, mock responses, and validate that your frontend sends the right data to your backend — all within end-to-end test scenarios where the browser and API are exercised together. Network
Testing
Pulumi infrastructure code is real programming-language code, so it deserves real tests. Pulumi's SDK provides a mock framework for unit tests (no cloud required) and an Automation API for integration tests against ephemeral stacks. This guide covers both layers in Go and Python, with CI patterns for