Equipment maintenance scheduler
A small system that tracks running hours, decides when each machine is due, and handles the thing every maintenance system pretends does not happen: jobs get put off, usually for good reasons, and the deferral is where the risk accumulates. Seven posts on the same system, one diagram at a time, with a cost breakdown and an engineering reference at the end.
- 01
An equipment maintenance scheduler on AWS for a few dollars a month
The whole system on one page — usage, due, deferred — and the deliberate decision to treat deferral as normal rather than as an exception.
- 02
How the interval gets decided
Why usage beats calendar, how to handle equipment that reports nothing, the whichever-comes-first rule, and the case against servicing too often.
- 03
How a deferral gets recorded
Why deferral must be a first-class action, what the record contains, how repeated deferrals escalate, and how the accumulated debt is reported.
- 04
Which jobs cannot be deferred
What makes an inspection statutory, why it needs its own track with no deferral path, how certificates are stored, and the equipment that must stop.
- 05
What the history tells you
How completed job records inform interval changes, which machine dominates the cost, what deferral reasons reveal, and what to report.
- 06
What the equipment maintenance scheduler costs
About $1 a month. One Bedrock read per asset is the only line that grows; the queue, the table, the mail and the storage are rounding errors. Plus the three ways the bill could surprise you.
- 07
Engineering reference: the equipment maintenance scheduler architecture
Same system, drawn purely for engineers. Service names, region, Lambda inventory, IAM scopes, the schemas and the exact model id.
Frequently asked questions
- What is an equipment maintenance scheduler?
- A small serverless system that tracks equipment usage, works out what is due, records deferrals explicitly, and keeps statutory inspections separate from discretionary servicing.
- Why schedule on running hours instead of months?
- Because a machine that ran four hundred hours needs the same attention as one that ran four hundred hours, regardless of whether that took two months or eight.
- Is deferring maintenance always bad?
- No, and pretending otherwise is why deferrals get hidden. The post on this argues for making deferral a first-class recorded decision with a name on it.
- What is a statutory inspection?
- An inspection required by regulation rather than by the manufacturer — lifting equipment, pressure systems, electrical testing. They cannot be deferred and are handled separately.
- What does it cost to run?
- A couple of dollars a month. See part six.