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57 articles
Performance
Core Web Vitals: The Complete Guide to LCP, INP, and CLS
A practical guide to Core Web Vitals — what LCP, INP, and CLS measure, the thresholds Google uses, how to read field vs lab data, and a prioritized plan to fix each one.
Jun 30, 2026 · 9 min read
Database
PostgreSQL Performance: A Practical Guide to Indexes, Query Plans, and Pooling
A practical Postgres performance guide: read query plans with EXPLAIN, index the right columns, kill N+1 queries, and pool connections so the database scales.
Jun 30, 2026 · 11 min read
AI Engineering
Reranking Explained: Cross-Encoders and the Precision Step
How reranking turns high-recall retrieval into high-precision context: cross-encoders vs bi-encoders, where rerankers fit in a RAG pipeline, and the cost.
Jun 29, 2026 · 8 min read
AI Engineering
Vector Search Explained: Dense vs Sparse vs Hybrid
How vector search actually retrieves text: dense embeddings vs sparse keyword search, why hybrid wins, and how to fuse the two with reciprocal rank fusion.
Jun 28, 2026 · 5 min read
AI Engineering
What Is RAG? A Practical Guide to Retrieval-Augmented Generation
What RAG is, when to use it, and how the retrieval pipeline actually works — chunking, embeddings, hybrid search, reranking, and evaluation, end to end.
Jun 28, 2026 · 7 min read
AI Engineering
RAG Isn't Dead — But Your Chunking Strategy Probably Is
Most failing RAG systems don't have a model problem, they have a retrieval problem. Here's how chunking, embeddings, and reranking actually decide whether your answers are any good.
Jun 22, 2026 · 5 min read
Performance
INP Is the Core Web Vital That Quietly Broke Your Lighthouse Score
Interaction to Next Paint replaced First Input Delay as a Core Web Vital. If your site felt fast in 2023 and 'got slow' since, INP is probably why — and the fix is mostly about your main thread.
Jun 18, 2026 · 4 min read
TypeScript
as const: The Assertion That Unlocks Literal Types
as const tells TypeScript to infer the narrowest possible types and make values readonly, turning loose objects into precise literal data.
Jun 15, 2026 · 5 min read
Architecture
The Outbox Pattern: Reliable Messaging Without Distributed Transactions
Update your database and publish an event atomically — without two-phase commit — by writing events to an outbox table first.
Jun 15, 2026 · 5 min read
Rust
Lifetimes Explained Without the Scary Diagrams
A plain-language take on Rust lifetimes: what the apostrophe annotations mean, why elision hides most of them, and when you actually write one.
Jun 15, 2026 · 5 min read
DevOps
Zero-Downtime Deploys With Rolling Updates
How Kubernetes rolling updates work, the settings that actually deliver zero downtime, and the probe and shutdown details teams miss.
Jun 15, 2026 · 6 min read
Security
Supply-Chain Attacks: Auditing Your Dependencies
Your app is mostly code you didn't write. How dependency supply-chain attacks happen and a practical playbook for auditing what you ship.
Jun 14, 2026 · 6 min read
Database
Postgres JSONB: When to Use It and When It Bites
A field guide to PostgreSQL JSONB: the genuinely good use cases, GIN indexing, and the modeling traps that bite teams later.
May 29, 2026 · 6 min read
AI Engineering
Guardrails: Validate LLM Output Before It Reaches Your Users
An LLM will confidently return malformed JSON, leaked prompts, or unsafe content. Treat its output as untrusted input and validate it like you would a form submission.
May 28, 2026 · 4 min read
Security
Secrets in Environment Variables: The Leaks You Don't See
Env vars feel like the safe place for API keys and passwords. Here are the quiet ways they leak — and how to keep secrets out of sight.
May 21, 2026 · 6 min read
Performance
Bundle Size: What's Actually Inside Your JavaScript
Your production bundle is bigger than you think, and you probably can't name half of what's in it. Here's how to look inside and cut the weight that matters.
May 20, 2026 · 5 min read
Architecture
Why a Modular Monolith Beats Microservices (for Most Teams)
A well-structured modular monolith gives you clean boundaries and fast iteration without the operational tax of distribution.
May 14, 2026 · 5 min read
TypeScript
Type-Safe API Calls Without a Code Generator
You don't need an OpenAPI pipeline to get end-to-end types on fetch. Validate responses at the boundary and let inference do the rest.
May 14, 2026 · 5 min read
AI Engineering
Cutting LLM Cost Without Cutting Quality: Model Routing + Caching
Most LLM bills are bloated by sending every request to your biggest model. Routing and caching cut cost dramatically while holding quality steady.
May 11, 2026 · 5 min read
DevOps
Your CI Is Slow Because of Cache Misses
Most slow pipelines are not compute-bound, they are re-downloading and rebuilding everything. A practical guide to fixing CI cache misses.
Apr 28, 2026 · 5 min read
Database
N+1 Queries: The Silent Performance Killer
What the N+1 query problem is, why ORMs cause it by default, how to spot it, and the patterns that eliminate it for good.
Apr 22, 2026 · 6 min read
Rust
Error Handling in Rust: Result, the ? Operator, and thiserror
From matching on Result by hand to clean propagation with ?, plus how thiserror removes the boilerplate from custom error types.
Apr 22, 2026 · 5 min read
Security
SQL Injection Still Works in 2026 — Here's Why, and How to Stop It
SQL injection is decades old and still breaching databases. Why it survives modern frameworks, and the parameterized patterns that kill it.
Apr 18, 2026 · 6 min read
React
Suspense and Streaming: Render UI Before the Data Arrives
Suspense lets React show fallback UI while a component waits, and streaming sends HTML in pieces. Together they kill the all-or-nothing loading spinner.
Apr 16, 2026 · 5 min read
AI Engineering
Embedding Drift: When (and How) to Re-Index Your Vector Store
Your RAG retrieval quality decays silently as data, models, and queries shift. A practical guide to detecting embedding drift and re-indexing safely.
Apr 15, 2026 · 5 min read
React
Controlled vs Uncontrolled Inputs: The React Form Decision You Keep Getting Wrong
Every laggy form and 'why won't this update' bug traces back to one choice: who owns the input's value — React state or the DOM. Here's how to decide.
Apr 12, 2026 · 4 min read
Performance
Debounce, Throttle, and the Event-Loop Tax
Scroll, resize, input, and mousemove fire faster than your code can keep up. Debounce and throttle are how you stop paying the event-loop tax — if you pick the right one.
Apr 8, 2026 · 4 min read
Architecture
Event-Driven Architecture Isn't Free: The Cost of Eventual Consistency
Decoupling with events buys scalability and resilience, but you pay in eventual consistency, ordering bugs, and harder debugging.
Apr 8, 2026 · 5 min read
TypeScript
Generics That Don't Make People Cry
Generics are not academic line noise. Used with a few simple rules they make functions reusable and self-documenting without the pain.
Apr 8, 2026 · 5 min read
AI Engineering
Structured Outputs Beat Prompt-and-Pray JSON Parsing
Begging a model for JSON and hoping it parses is a bug waiting to happen. Schema-constrained structured outputs make it a guarantee. Here's how.
Mar 24, 2026 · 5 min read
DevOps
Liveness vs Readiness Probes: The Difference That Takes Down Deploys
Misconfigured Kubernetes probes cause restart loops and dropped traffic. Here is exactly when to use liveness, readiness, and startup probes.
Mar 20, 2026 · 5 min read
React
Keys in Lists: The Subtle React Bug You Ship Every Time You Get Them Wrong
Using array index as a key seems harmless until inputs swap values, animations jump, and state attaches to the wrong row. Here's what keys actually do.
Mar 19, 2026 · 4 min read
Rust
Box, Rc, Arc: Choosing the Right Smart Pointer
A decision-oriented guide to Rust's heap pointers, when single ownership beats shared ownership, and where Arc earns its atomic cost.
Mar 18, 2026 · 5 min read
Database
Connection Pooling: Why Your Database Falls Over at 100 Users
Why a database that handles 20 connections collapses at 100, and how connection pooling with tools like PgBouncer fixes it.
Mar 18, 2026 · 6 min read
TypeScript
Discriminated Unions: Modeling State That Can't Be Wrong
Stop juggling isLoading, error, and data as separate fields. Discriminated unions make impossible states unrepresentable in TypeScript.
Mar 12, 2026 · 5 min read
Security
JWTs: Stop Storing Them in localStorage
Why localStorage is the wrong home for your JWTs, how XSS turns it into a token vault for attackers, and what to do instead.
Mar 12, 2026 · 5 min read
Architecture
The Saga Pattern and the Distributed-Transaction Trap
You can't BEGIN..COMMIT across services. Sagas trade atomic transactions for choreographed steps and compensating actions.
Mar 12, 2026 · 5 min read
Performance
Image Optimization Is the Single Biggest LCP Win
On most pages the Largest Contentful Paint element is an image. Get that one image right and you fix the metric users feel most. Here's the playbook.
Mar 11, 2026 · 4 min read
React
useEffect Is Not a Lifecycle Method (Stop Treating It Like One)
Most useEffect bugs come from porting componentDidMount habits to hooks. Here's the synchronization model that makes effects predictable.
Mar 9, 2026 · 5 min read
AI Engineering
Agentic Tool-Calling Loops That Don't Spiral Out of Control
Agents call tools in a loop. Without the right guardrails that loop burns money, hangs, or repeats itself forever. Here's how to keep it bounded.
Mar 3, 2026 · 5 min read
Performance
The Cost of Re-Renders: Memoization That Actually Helps
Most React memoization is cargo-culted and does nothing. Here's how to tell which re-renders cost you and where useMemo, useCallback, and memo earn their keep.
Feb 14, 2026 · 5 min read
Rust
Async Rust, Two Years In: What Actually Got Better
A grounded look at how async Rust matured, from async fn in traits to clearer ecosystem defaults, and where the sharp edges still are.
Feb 12, 2026 · 5 min read
Database
Index-Only Scans, Explained With Real Query Plans
How Postgres index-only scans avoid touching the table heap, when they kick in, and how the visibility map quietly decides everything.
Feb 12, 2026 · 6 min read
DevOps
Multi-Stage Docker Builds: Smaller, Faster, Safer Images
How multi-stage builds shrink images, exclude build tooling from production, and shorten your attack surface, with copy-paste examples.
Feb 12, 2026 · 5 min read
React
The React Compiler Is Stable — What Actually Changes for You
The React Compiler memoizes your components automatically. Here's what it does, what it doesn't, and which habits you can finally drop.
Feb 12, 2026 · 5 min read
Architecture
Idempotency Keys: The API Pattern That Prevents Double Charges
A client retries a payment after a timeout and the customer gets billed twice. Idempotency keys make retries safe by design.
Feb 10, 2026 · 5 min read
TypeScript
satisfies: The Operator You Should Be Using
The satisfies operator validates a value against a type without widening it, so you keep precise inference and still catch mistakes.
Feb 10, 2026 · 5 min read
AI Engineering
Evals Are Unit Tests for Non-Deterministic Systems
You wouldn't ship code without tests. Stop shipping prompts without evals. A practical guide to building evaluation suites for LLM features.
Feb 9, 2026 · 5 min read
Security
The Auth Bug That Took Down Our Entire Weekend
A post-mortem on a broken access control bug that exposed other users' data — what went wrong, how we caught it, and how to prevent it.
Feb 9, 2026 · 5 min read
AI Engineering
Prompt Caching: The Optimization Most LLM Teams Skip
Prompt caching can cut latency and cost on repeated context by an order of magnitude. Here's how it works and why most teams leave it on the table.
Jan 12, 2026 · 6 min read
Performance
I Profiled 50 React Apps. Here's What Slows Them All Down
After profiling 50 production React apps, the same five problems showed up again and again. None of them were exotic — and all of them were fixable.
Jan 9, 2026 · 5 min read
Database
Database Indexes Are Not Magic: A Mental Model
A practical mental model for how database indexes really work, why they speed up reads, and the hidden costs you pay on writes.
Jan 8, 2026 · 6 min read
Architecture
The Hidden Cost of Microservices Nobody Talks About
Microservices promise scale and autonomy, but the real bill arrives as operational tax, network failure modes, and cognitive load.
Jan 5, 2026 · 5 min read
React
React Server Components: The Mental Model That Finally Clicks
Server Components aren't 'SSR 2.0' or a faster useEffect. Here's the mental model that makes the boundary between server and client finally make sense.
Jan 5, 2026 · 6 min read
Rust
Rust Ownership Finally Clicked When I Stopped Fighting It
The mental shift that turned the borrow checker from an enemy into a design partner, with practical patterns for moves, borrows, and clones.
Jan 5, 2026 · 6 min read
DevOps
Stop Writing Dockerfiles Like It's 2017
A modern Dockerfile playbook: build cache ordering, non-root users, pinned digests, BuildKit, and the habits worth unlearning.
Jan 5, 2026 · 5 min read
TypeScript
Why Your TypeScript Types Are Slowing Down Your Editor
Autocomplete that stalls and red squiggles that lag are usually a type-checking problem. Here is how to find and fix the expensive types.
Jan 5, 2026 · 5 min read