Make reliability a shared priority, not just tech-speak. This session shows you how to frame SLOs in business terms, engage stakeholders, and use clear metrics to align technical and business priorities.

The outline of the talk:
- Engineers care about reliability, and we have developed a language to talk about it
- We count the nines (9s) of availability, define error budgets, measure MTTR and MTBF
- Why is it so hard then to convince our business counterparts about doing technical improvements?
- Because our language sounds intimidating and disconnected from reality.
- We fail to explain the actual value of reliability
- The key question of reliability:
- How much does it cost when your service is down for one hour?
- Don't ask how many nines of availability a service should have, ask how much cost is acceptable?
- SLO formula
- X must be true Y percentage of the time
- X is your definition of success
- Y is your threshold
- Two level of how you can measure success:
- Technical level: A service is running, DB is working, API returns a 200 status code.
- Business level: The business process is working. 99.9% of transfers are successful, 99% of reports are generated within 30 seconds, etc.
- Aim to define SLO on the business level.
- From measuring to prioritization
- Benefits of measuring SLO on the business level:
- You know the costs of outages
- You know the cost of bad architecture
- You know the cost of slow processes
- Your data points are facts from the pasts
- Business plans and new features are guess work about the future
- It's easier to talk about priorities when you numbers are solid.
- You're using the same units to compare tech improvements and features.
- Use error budgets to drive improvement
- Review how your systems perform against SLO.
- If your SLO is 99.9%, you allow yourself to fail in 0.01% of cases. This is your error budget.
- What do you do when you exceed the budget?
- Code freeze
- Prioritize immediate improvements to recover reliability.
- Conduct postmortems
- "Do better next time" is not a strategy.
- Make reliability a first-class citizen.
- Report SLOs together with business metrics.
- Remind your stakeholders that availability is your most important feature.