"Clever" is a bad word
“Clever” applied to designs or code is a bad word. Compliments include: “simple” or “dumb”.
Design
Beware the word “we” in designs
Precise names lead to clearer designs. E.g., “we” referring strictly to people.
Proactive identification of reliability issues
Systematically enumerate dependencies and failure modes. Prevent, mitigate, or accept them.
Evolvable serialized filters
An evolvable way of serializing arbitrary filters, here as JSON, but broadly applicable.