My notes from the DevOps Handbook

by Gene Kim, Jez Humble, Patrick Debois, John Willis

The Second Way: Principles of feedback

Enable fast and constant feedback from right to left at all stages of the value stream.

Goal: ever safer and more resilient systems of work

In technology the work happens almost entirely within complex systems with a high risk of catastrophic consequences.

System of work safer by

• information flow
• fast
• frequent
• high quality
• throughout the value stream

Detect and remediate problems as they are smaller, cheaper and easier to fix.

Working safely within complex systems

Complex system - single person is unable to see it as a whole and understand how everything fits together.

• interconnectedness
• tightly coupled
• behavior impossible to explain in terms of components

Characteristics of a complex system - doing the same thing twice will not necessarily lead to the same result.

Conditions for a safer system

• managed complex work
• problems swarmed and solved
• new local knowledge -> global in the organization
• leaders create other leaders

See problems as they occur

We must constantly test our design and operating assumptions in complex system.

Create feedback and feed forward loops to be able to invalidate assumptions.

Feedback loops are a critical part of learning organizations and systems thinking.

Feedback and forward loops whenever the work is performed, all stages of the value stream. We achieve this by automated build, integration and test processes.

Pervasive telemetry - detect if components are operating in production not as expected.

Feedback loops also inform us how to prevent problems in the future.