TLDR Dev 2025-11-19

Previews only work if they're actually like prod. This step-by-step shows how a minimal .upsun/config.yaml, and one deploy hook clonesdata, files, and services on every branch.

Push a branch, get a custom preview env URL, reproduce the bug, validate the fix, merge with receipts.

Same topology, same routes, fresh safe data. No mocks, no kubectl.

If you've outgrown flaky staging, this is the simplest way to get honest tests and faster reviews. Keep configuration in Git, and let CI run against the real topology.

• Read the walkthrough• Watch the 45-second demo• Start free on Upsun

Cloudflare had a large outage yesterday due to a faulty configuration file in its Bot Management system, which was triggered by a database permissions change. This larger-than-expected file overloaded the network's traffic routing software, resulting in widespread HTTP 5xx errors and impacting services like Turnstile, Workers KV, and Access. The issue was not a cyber attack. The team was able to resolve it by stopping the faulty file propagation and restoring an earlier version, bringing systems back to normal by 17:06 UTC.

This exploration into making TypeScript immutable by default was inspired by languages like Rust. By setting the `noLib` flag and creating a custom `lib.d.ts` file, this dev successfully made arrays and Records immutable unless explicitly declared as `MutableArray` or `MutableRecord`. This was done by defining read-only properties and omitting mutable methods in the default type definitions.

The CSS Custom Highlight API is a performant alternative to traditional syntax highlighting methods that rely on numerous DOM elements. The API can help style arbitrary text ranges directly using CSS without modifying the DOM, resulting in faster rendering and reduced memory consumption. It's supported in modern browsers and is done by defining CSS styles using the `::highlight()` pseudo-element and registering text ranges with the browser's highlight registry.

A recent Cloudflare outage took down many websites, showing the risk of relying on centralized services as single points of failure. Many smaller websites don't actually need Cloudflare's DDoS protection and are unnecessarily exposed to its potential downtime. Instead of Cloudflare, it's possible to just use a round-robin DNS setup with a backup server for true redundancy.

Front-end developers can write better code by following the "rule of three" (only refactor code after you've written the same thing three times to avoid over-engineering) and "make it work, make it right, make it fast" (prioritize getting code to function correctly before optimizing for performance). These guidelines help devs make better decisions while coding and avoid common pitfalls like premature optimization and unnecessary complexity.

Tired of credential stuffing threats? Clerk's new "Client Trust" feature automatically requires a second factor on any new device—protecting users, even if their password gets leaked in a 0-day attack. No configuration, no guesswork. Stop worrying about credential leaks: get invisible, decisive security from day one!

Guts is a Go library that converts Golang types to TypeScript for consistent type definitions across frontend and backend applications. Unlike command-line utilities, Guts is designed for programmatic customization and easier package resolution. It uses the TypeScript compiler API to make sure generated TypeScript is semantically correct and aligned with the latest language features.

Google has launched Gemini 3, its most intelligent AI model yet. Designed to help users bring any idea to life through state-of-the-art reasoning and multimodal capabilities, Gemini 3 outperforms previous models on key AI benchmarks and introduces a "Deep Think" mode for even more complex problem-solving. It is being rolled out across Google products, including Search, the Gemini app, AI Studio, Vertex AI, and a new agentic development platform called Google Antigravity.

Google's Antigravity is a new AI-powered agentic development platform built on Gemini 3. Antigravity has both an AI-powered IDE experience ("Editor view") and an agent-first interface for orchestrating multiple agents ("Manager surface").

AI-generated advertisements are becoming mainstream. Major brands like Taylor Swift, Google, and Coca-Cola have begun using AI tools to create marketing content. Swift's promotional videos were confirmed to be AI-generated using Google's video generation tools. The trend is accelerating rapidly. Surveys predict that 39% of digital video ads will use generative AI by next year. While early AI-generated ads faced some controversy, consumer backlash appears to be weakening.

AI codegen tools are creating a new form of technical debt (“AI slop”): bloated, buggy code that doesn't have proper architecture and includes redundant functions. To address this problem, AI-powered code review tools act as automated senior engineers, analyzing code for security vulnerabilities, performance issues, and architectural problems. This leads to an agentic software development lifecycle where specialized AI agents handle generation and review tasks, while human developers act as architects instead.

In 1996, Quake faced challenges adapting to the shift from MS-DOS to Windows 95 while also supporting emerging technologies like 3D acceleration and the Internet. id Software created a single executable, quake.exe, compatible with both DOS and Windows by using djgpp's DPMI client and the Windows 95 DPMI server. For TCP/IP support in DOS, Quake relied on a costly third-party TSR, but in Windows 95, it utilized Mpath's "Chunnel" technology, a complex system involving virtual device drivers and DLLs to bridge the DOS executable with the Windows TCP/IP stack.

Tokenflood is a load testing tool for instruction-tuned LLMs that simulates arbitrary load profiles by defining prompt lengths, prefix lengths, output lengths, and request rates.

Rebecca Heineman (Burger Becky) recounts her challenging experience porting Doom to the 3DO console amidst unrealistic expectations, limited resources, and a chaotic development process.

Google's new Gemini 3 Pro model is competitive with other leading models in benchmarks, multimodal support, and pricing.

GitHub no longer uses toast notifications due to significant accessibility and usability issues.