> Term
Freshness Contract
An agreed-upon timeframe indicating how long cached data can be served before it is considered unacceptably stale.
Detailed Explanation
A freshness contract explicitly sets the expectation between frontend and backend about data accuracy. It prevents the infinite debate of 'why isn't the UI updating?'
Why It Matters
It forces product managers and engineers to mathematically define what 'real-time' actually means for a specific feature.
Common Failure Mode
Practical Example
Production Manifestation
Time-To-Live (TTL) settings in Redis, HTTP Cache-Control headers, or background polling intervals.
Frequently Asked Questions
What is Freshness Contract in short?
An agreed-upon timeframe indicating how long cached data can be served before it is considered unacceptably stale.
What is the most common failure mode?
Giving a highly dynamic metric (like stock availability) a 24-hour freshness contract because 'it makes the page load faster'.
AI Summary
An agreed-upon timeframe indicating how long cached data can be served before it is considered unacceptably stale. It forces product managers and engineers to mathematically define what 'real-time' actually means for a specific feature.