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Systems 2026-09-23

[Wiblog Part 2] Redefining the Product Direction After Beta Feedback

How beta users' questions and behavior changed Wiblog's customer hypothesis, onboarding, B2C/B2B direction, and value proposition.
Systems 2026-09-18

[Wiblog Part 1] From Topic Idea to Generated, Published, Search-Visible Content

From topic ideas to publishing and search visibility
Systems 2026-09-16

Part 2 — Four People Sharing One VPS — Role-Based Access, Homes, and Ports

Two developers, a designer, and a marketer on one server
Systems 2026-09-15

Part 1 — Why We Chose a 96GB VPS Instead of Four 16GB MacBooks

A dev server that grew from 1.2GB to 3.7GB in 4 hours
Systems 2026-09-08

The In-App Browser Eats Your Social Login Button — and Hard Logins Lose Users Instantly

Detect, escape, fall back — for drop-offs no log catches
DevOps 2026-09-08

Switching LLM Accounts at 88% — Manually First, Then Automatic Failover at 80%

From a Grafana 88% alert to automatic failover at 80%
Systems 2026-08-20

Why I Started Strongly Recommending Custom Domains — Notes from a Blog Indexing PoC

What indexing experiments and domain migrations taught me about the default address a blogging platform provides
DevOps 2026-08-18

How I Cut AI Blog Generation Costs by Reducing Duplicate Searches and Failed Retries

Recomputing 15 topics from logs: ₩309 down to ₩150
Systems 2026-08-17

Eight Cheap Calls Beat One Good One — Why I Removed the Model That Wrote Better

Why fast repeated Grok calls beat the better writer
Systems 2026-08-10

Keyword Discovery: 25 Seconds Down to 0.2, by Calling Search Autocomplete

Replacing two LLM calls with one autocomplete request
Reliability 2026-07-23

Connecting a Custom Domain with One Click — a Pipeline Built Around 'You Can't Speed Up DNS Propagation'

Four purchases, four failures, one 3-stage pipeline
Reliability 2026-07-20

Taking Caddy Out of the Deploy Path — the Structural Problem Was Touching a SPOF Automatically

Removing 60–100s outages, then the last 5 seconds
Systems 2026-07-14

[Threads Marketing Agent, Part 3] Multi-Account Engagement Automation with an Anti-Detect Browser — Brain/Hands Split, CDP Driving, Detection-Aware Pacing

VPS as the brain, Mac mini as the hands
Systems 2026-07-06

[Threads Marketing Agent, Part 2] Designing a Generation Pipeline — A 4-Axis Content Model, Queue-Based Scheduling, 3-Layer Attribution

A 4-axis content model, an SQLite queue, and 90% bot clicks
Systems 2026-06-29

[Threads Marketing Agent, Part 1] Designing a Crawler That Beats Three Tiers of Anti-Bot — From TLS Fingerprints to CDP Detection

The real bottleneck was crawling, not the LLM
Scaling 2026-05-29

Scaling QPS 10x in Production: 3 Strategies That Actually Move the Needle

Caching, database tuning, and moving side work off the request
Reliability 2026-05-17

[Messenger Load-Testing, Part 3] FCM to a Queue, Swallowed Failures to Sentry — Cleaning Up the Message-Send Handler

Isolating external I/O and surfacing swallowed errors
Reliability 2026-05-11

[Messenger Load-Testing, Part 2] There Was a Deadlock Hiding in AI-Generated Code — How We Replaced `unreadCount` with `lastReadAt`

42.8% errors in 9 minutes, caused by one updateMany
Scaling 2026-05-04

[Messenger Load-Testing, Part 1] Building a Reusable Load-Test Environment — Make-based IaC, Observability, and Auth Seeding

A 7-node production clone, rebuilt with one make command
Reliability 2026-03-29

Why You Should Never Use KeyDB as a Pub/Sub Broker for Centrifugo

Five years of hang issues behind a perfect-looking active-replica
Reliability 2026-03-26

Building a Crash-Resilient, End-to-End Meeting Recording Pipeline in the Browser

Surviving a 300MB heap and tab crashes with 5-minute savepoints