Tech Blog
Engineering Blog
Written by the people who actually run these systems in production. Every article records what broke, why, and how it was fixed — down to the file and line the claim came from. Published in both English and Japanese.
- migrate_image_tag drifts from live after concurrent deploys
- dpm set-device-owner Launches the App Before prefs Is Set
- gcloud ADC Expires After ~44h: Reauthentication failed Fix
- allUsers + objectViewer on GCS Grants list, Not Just get
- Valid Token, Wrong Scope: an IDOR via design/date Parameters
- vercel inspect won't show which commit is live
- term_months Display Drifts From Amount After Term Extension
- @media(max-width:899px) Leaks Into a Scaled Signage Preview
- semgrep --config=auto Turns main Red, No Code Changed
- amount_unset: Stripe's 7-Day Auto-Switch Never Fires
- sp.units Query Param Shows 5x Price for a 1-Unit Invite
- gen-og.ts Cache Hid an Overwritten OG Image on 91 Posts
- Next.js 15.1.6 Got Blocked by Vercel as a Vulnerable Version
- pnpm-lock.yaml Made Vercel Misdetect an npm Project as pnpm
- Next.js Server Action Fail-Open: error Read as Success
- 01.dnsv.jp Full-Zone Replace Deletes Unrelated A Records
- console_name.sql Collided Again 58 Minutes Later
- fail-closed Guard Was Missing From Two Other Write Paths
- reminder_log_kind_check Regex Test Was a False Green
- RegExp.test False Positive: "unsigned" Matches "signed"
- Google Custom Search API 403: Switched to Brave Search API
- copyOneDay Overwrite Silently Drops Pinned Notices
- supabase-js count Query Returns null on Failure
- start_month Missing Lets a Contract's Period Go NULL
- Next.js Middleware Missing an Exclusion Forces Login
- entity_id Was uuid, We Inserted a Token — 22P02
- A 200 OK That Crashes a Server Component
- PostgREST .or() Breaks Silently on a Comma
- Only system_admin Hits The Audit Log Foreign Key Constraint
- polynomial-redos: Missing ^ Made a Trim Regex O(n^2)