Service Level Objectives (SLOs)

When delivering an API, there's an inherent tension between quickly and consistently shipping features and ensuring that the service is stable, secure, and meets consumers' expectations for performance.

Once an API is in production, service quality becomes one of the most important API features. Often there are Service Level Agreements (SLAs) that the team must meet. Teams can strive for 100% availability and lightning-fast performance, but that would require immense resources in time, people power, and financial investment.

API teams must strike a balance, continuing to ship new features while maintaining reliability objectives. The API must stay reliable and performant enough that consumers do not notice and are not affected.

This section of the VA API Standards defines how to set desired service quality goals via Service Level Objectives (SLOs) and measures these objectives via Service Level Indicators (SLIs) to meet SLAs.