Brandon Wie | Software Engineer

Brandon (Seokhyun) Wie

All Posts EN / KR

Software engineer writing about backend systems, DevOps, and lessons learned building real products.

Backend engineer building production systems at scale — film school grad turned engineer, now leading backend at Moba. This blog collects what I've learned along the way.

Work

Arch Calendar — The Calendar That Remembers Everything · Lead Backend

Led backend from legacy to public launch — multi-account calendar sync, payments, and real-time updates processing 10M+ events at scale.

3B System — Public 3B architecture map · /system/3b

Sanitized system map for the 3B agent harness behind this site: layers, subsystems, decisions, and blog-series progress.

Project Crucio — AISecOps Knowledge Platform · Creator

Zero Trust security for generative AI — 6 polyglot microservices (Python + Go + Rust + TypeScript), Kafka event streaming, hash-chained audit, and full LGTM observability on hybrid GCP + NAS infrastructure.

Recent Posts

Jun 13, 2026 ↻

The pre-commit hook race that put my files in someone else's commit — Two sessions committing to one repo, a slow pre-commit hook, and `fatal: cannot lock ref HEAD`. The loud failure is the easy one — the quiet failure hands your staged files to the other session's commit under its message.

Jun 13, 2026 ↻

Serena MCP — Multi-Profile Setup for Claude Code (cpers/cwork) — Installing the Serena MCP server across a Claude Code dual-profile setup (cpers/cwork) plus Codex, including the four recommended hooks, the system-prompt override, and the non-obvious "installer writes to default ~/.claude.json, misses profile-specific stores" trap.

Jun 13, 2026 ↻

Claude Code Multi-Profile HUD Setup — Running Claude Code with multiple accounts requires careful HUD configuration to show correct per-account usage stats. Here's how to fix cross-profile data leaks.

Jun 9, 2026 ↻

WAF Allowlist Patterns — Block-by-default WAF approach using route allowlisting. Stronger security than

Jun 9, 2026 ↻

Rust async channels with tokio — Choosing between tokio's mpsc, unbounded mpsc, and oneshot channels is a stream-vs-handoff decision, not a performance one.

Jun 7, 2026 ↻

When CLAUDE.md keeps overflowing, move the budget into your generator — The "Large CLAUDE.md will impact performance" warning kept coming back weeks after every trim. It stopped for good once the byte budget moved out of author discipline and into the generator that assembles the file — as a per-rule warning, a total hard-fail, and a rendered-file ceiling.

Jun 7, 2026 ↻

Why your updater keeps re-enabling the Claude plugins you disabled — I kept a couple of plugins deliberately off, ran my updater, and they came back on. The script provably never re-enabled anything — because the re-enable was not the script's to begin with. Here is the snapshot-and-reassert guard that stopped the toil.

Jun 7, 2026 ↻

State-invariant flag drift — recovery via reconciliation pass — A boolean lifecycle flag kept getting stuck on entries that could never reach the code path that clears it. Symptom-only fixes recurred. The durable fix was a third workflow that enforces the invariant the flag implies, independent of how the flag got set.

Jun 7, 2026 ↻

Session-State Dashboards: Merge, Don't Overwrite — Regenerating a cross-session dashboard two ways — overwrite, or merge-with-carry-forward — fails in opposite directions. Here is the rule I settled on, and why I eventually stopped tracking the dashboard in git at all.

Jun 5, 2026 ↻

tmux Smart Session Auto-Start — Auto-start tmux via an iTerm2 Profile Command (`tmux-smart-attach`) with numeric

→ See all 146 posts