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• eBPF Deep Dive — The VM, Verifier, XDP, and CO-RE That Made the Linux Kernel Programmable (2025)

  Injecting safe code into the kernel — that is the eBPF revolution. This post dissects eBPF from internals to practice: the VM and bytecode, the Verifier that enforces safety, maps (Hash/Array/Ring Buffer/Perf), program t

  2026-04-15 · 15 min read #ebpf#linux#kernel#xdp#observability

• A Deep-Dive Guide to the New Era of Edge Computing — Cloudflare Workers, Durable Objects, D1, Vercel Edge, Deno Deploy, Fastly, Fly.io, Turso, and Region-aware Architecture (2025)

  Edge computing, which began with Cloudflare Workers in 2017, became the default infrastructure of virtually every modern SaaS by 2024-2025. The UX bar of "50ms even on the opposite side of the earth" is the practical rea

  2026-04-15 · 15 min read #edge-computing#cloudflare-workers#durable-objects#d1#vercel-edge

• The Complete DNS Guide — Resolvers, DNSSEC, DoH/DoT, Anycast, CoreDNS, and Everything Else (2025) ♪ Listenable

  Everything about DNS — the history of the name system that started with hosts.txt, query flow (stub to recursive to root to TLD to authoritative), record types (A/AAAA/CNAME/MX/TXT/NS/SOA/SRV/CAA/HTTPS/SVCB), EDNS0 and p

  2026-04-15 · 25 min read #dns#dnssec#doh#networking#security

• DuckDB Internals Deep Dive — Embedded OLAP, Vectorized Execution, Morsel-Driven Parallelism, and Storage Format (2025) ♪ Listenable

  DuckDB — the analytical engine that replaces Pandas and brings a ClickHouse-class OLAP database into your process. This post dissects DuckDB from the ground up: the journey from Mark Raasveldt and Hannes Mühleisens 2018

  2026-04-15 · 24 min read #duckdb#olap#database#columnar#vectorization

• Game Development Complete Guide 2025: Unity vs Unreal vs Godot, ECS, Multiplayer, Optimization

  Everything about game development! Unity DOTS/ECS, Unreal Engine 5 (Lumen/Nanite), Godot 4, game loops, physics engines, multiplayer (Netcode/Mirror), performance optimization (draw calls/batching), mobile vs console vs

  2026-04-15 · 12 min read #game-development#unity#unreal-engine#godot#ecs

• Distributed Systems Complete Guide — Clocks, Consensus, Event Sourcing, Saga, CRDT, Failure Patterns (Season 2 Ep 12, 2025)

  A distributed system looks like "several computers cooperating," but what it really is: "several computers whose clocks disagree, some of them broken, reaching agreement across a network that loses and delays messages."

  2026-04-15 · 13 min read #distributed-systems#consensus#raft#paxos#lamport-clock

• DNS Deep Dive — Resolution, Caching, DNSSEC, DoH/DoT, Anycast, and 1.1.1.1 Internals (2025)

  Trillions of times per day, yet most engineers understand DNS only superficially. This guide dissects DNS from first principles: hierarchical namespace, recursive/iterative resolution, caching and TTLs, record types (A/A

  2026-04-15 · 12 min read #dns#networking#dnssec#doh#anycast

• Frontend Testing 2025 — Vitest, Jest, Bun, Testing Library, Playwright, Storybook, MSW, Visual Regression, AI (S6 E11)

  Jest is no longer the default. Vitest won the unit-test race, Playwright displaced Cypress for e2e, Storybook 8 made component tests first-class, and AI-generated tests became table stakes. This is a practical guide to a

  2026-04-15 · 6 min read #frontend#testing#vitest#jest#bun-test

• Distributed Databases 2025 — CockroachDB, Spanner, TiDB, Yugabyte, Aurora DSQL, Neon, PlanetScale, Turso, D1 (S7 E3)

  The "just use one database" era is over. In 2024–2025 distributed SQL (CockroachDB, Spanner, TiDB, Yugabyte), serverless Postgres (Neon, Supabase, PlanetScale, Aurora DSQL), and edge SQLite (Turso/libSQL, Cloudflare D1)

  2026-04-15 · 11 min read #database#distributed-sql#postgresql#cockroachdb#spanner

• Distributed Consensus Deep Dive — Paxos, Raft, ZAB, FLP, etcd, ZooKeeper, KRaft, BFT, CRDT (2025)

  Why is it hard for a distributed system to merely "agree"? The shock of the FLP impossibility result, Lamport's Paxos and its infamous unintelligibility, how Raft changed the landscape, ZooKeeper's ZAB, the birth of KRaf

  2026-04-15 · 15 min read #distributed-systems#consensus#paxos#raft#etcd

• The Complete Developer Writing Guide: Design Doc, RFC, Blog, Book, Conference Talk (2025) ♪ Listenable

  80% of a Staff+ engineer's influence comes from writing, not code. Breaking down Google's Design Doc template, the RFC processes of Rust/Python/Node, the blogs of Julia Evans/Dan Luu/Stratechery, the O'Reilly/Manning pub

  2026-04-15 · 17 min read #writing#design-doc#rfc#tech-blog#conference-talk

• Anatomy of Famous Postmortems — Learning From the Failures of Cloudflare, Fastly, AWS, Knight Capital, and GitLab

  Cloudflare 2022 BGP, Fastly taking down half the internet in 2021, the AWS S3 typo of 2017, Knight Capital losing $440M in 8 minutes, the GitLab DB wipe, and more — the patterns and lessons extracted from famous failures

  2026-04-15 · 12 min read #postmortem#sre#outage#reliability#culture

• eBPF Complete Guide — A Tiny VM Inside the Kernel: Verifier, JIT, CO-RE, Maps, Attach Points, XDP, LSM, sched_ext (2025) ♪ Listenable

  Everything about eBPF — from cBPF in 1992 to eBPF in 2014 to schedext in 2024. The 11-register virtual machine ISA, the verifier's static analysis, JIT compilation, BTF and CO-RE, 17+ BPF map types, 200+ helper functions

  2026-04-15 · 31 min read #linux#kernel#ebpf#bpf#xdp

• 2025 Developer Tools Complete Guide: Modern Stack, AI Tools, Productivity, Emerging Tech

  Every tool a developer should know in 2025! Modern IDEs (Cursor/Claude Code), terminal tools (Warp/Ghostty/Zed), build tools (Bun/Vite/Turbopack), AI coding assistants, productivity workflows, emerging tool trends.

  2026-04-15 · 9 min read #developer-tools#modern-stack#productivity#ai-tools#ide

• The Complete Product Sense Guide for Engineers: Customer Empathy, JTBD, North Star Metric, AB Testing, PMF, Prioritization, and Roadmaps (2025~2026)

  "I am an engineer, product is the PM job" stops working in 2026. The three levels of customer empathy, the Jobs-to-be-Done frame, designing a North Star Metric, the failure patterns behind the 60% of AB tests that go wro

  2026-04-15 · 15 min read #product-sense#jtbd#north-star-metric#ab-test#pmf

• Docker BuildKit & Image Layers Complete Guide 2025: LLB, Cache Mount, Multi-Stage, OCI, Build Optimization Deep Dive ♪ Listenable

  Why is the same Dockerfile 10x faster with BuildKit? Image layer structure, BuildKit LLB, cache mount, multi-stage builds, OCI format, reproducible builds — a complete 720-line analysis of everything about modern contain

  2026-04-15 · 26 min read #docker#buildkit#oci#image-layer#cache-mount

• The Complete Guide to Developers and the Next Ten Years of AI: How to Survive and Thrive in the Copilot/Cursor/Claude Era (2025)

  How Copilot, Cursor, Claude Code, and Devin are changing daily development work. Three scenarios (optimistic, neutral, pessimistic) for how the job changes over the ten years from 2025 to 2035. How the junior role change

  2026-04-15 · 15 min read #ai-future#copilot#cursor#claude-code#agentic-coding

• Design Systems and Tokens 2025 — Complete Guide: Radix, shadcn/ui, Chakra, Tamagui, Park UI, Ark UI, DaisyUI Compared, the W3C Design Tokens Standard, Figma Variables and Tokens Studio Integration, Component API Design, Accessibility, and Korean Enterprise Case Studies — Season 6 Ep 2

  A design system is not CSS. It is the shared language of a product team. A 2025 comparison of major component libraries (Radix, shadcn/ui, Chakra, Tamagui, Park, Ark, DaisyUI), Headless vs Styled philosophies, the W3C De

  2026-04-15 · 13 min read #design-system#design-tokens#radix#shadcn-ui#chakra

• DB Sharding & Partitioning Complete Guide 2025: Horizontal Scaling, Range/Hash/Directory, Resharding, Vitess

  Everything about database sharding! Horizontal vs vertical partitioning, shard key selection, Range/Hash/Directory/Geographic sharding, hot spot problems, resharding, distributed transactions, Vitess/Citus/CockroachDB co

  2026-04-15 · 15 min read #database#sharding#partitioning#horizontal-scaling#vitess

• Elasticsearch, OpenSearch, and Lucene Internals — Inverted Index, BM25, Sharding, Vector Search, Hybrid RAG (2025)

  Why is search hard? Lucene Segments and Merge, the math of Inverted Index, how BM25 beat TF-IDF, primary/replica shards and routing, Ingest pipelines, the Query DSL maze, kNN and HNSW, the 2021 Elastic vs AWS license war

  2026-04-15 · 11 min read #elasticsearch#opensearch#lucene#search#vector-search