Measured what was actually running in the account, and put every cost on one screen every day
Role
Investigation, implementation, operations
Period
2026.06 – 2026.09
Status
Operating
Stack
AWS, NCloud, Python, launchd, Cost Explorer
Inventory audit and decommissioning (2026.06)
What actually existed in the account: 2 EC2, 2 RDS, 1 ALB, 0 ECS. Not what the documents said.
An environment built for certification testing and then abandoned was decommissioned on June 30, cutting monthly cost by 64%.
The single cause of the August bill spike was the automatic RDS MySQL 8.0 Extended Support charge; a plan to resolve it via the 8.4 upgrade was drafted.
Cost dashboard (2026.08)
Hybrid design: five automated sources (OpenAI, Anthropic, AWS, NCloud, GitHub) plus manual entries.
Collected and deployed daily at 08:10 via launchd. Every date comes from one clock (today_utc()), a rule adopted after fixing a cache-key bug in September where local and UTC dates were mixed.
For NCloud, the current-month amount field must be used instead of the field that includes unpaid carry-over, or costs get double counted.
Savings review (2026.09)
Drafted confirmed savings (RDS 8.4, Savings Plan, annual billing, instance generation change, ECR, Agora) separately from items needing a decision (duplicate SaaS seats and the like) and reported them.