# Contribution guidelines

So you want to hack on Istio? Yay! Please refer to Istio's overall
[contribution guidelines](https://github.com/istio/community/blob/master/CONTRIBUTING.md)

  // the smallest value of such global default PriorityClasses will be used as the default priority.
  // +optional
  optional bool globalDefault = 3;

  // description is an arbitrary string that usually provides guidelines on
  // when this priority class should be used.
  // +optional
  optional string description = 4;

  // preemptionPolicy is the Policy for preempting pods with lower priority.
  // One of Never, PreemptLowerPriority.

  // the smallest value of such global default PriorityClasses will be used as the default priority.
  // +optional
  optional bool globalDefault = 3;

  // description is an arbitrary string that usually provides guidelines on
  // when this priority class should be used.
  // +optional
  optional string description = 4;

  // preemptionPolicy is the Policy for preempting pods with lower priority.
  // One of Never, PreemptLowerPriority.

  // the smallest value of such global default PriorityClasses will be used as the default priority.
  // +optional
  optional bool globalDefault = 3;

  // description is an arbitrary string that usually provides guidelines on
  // when this priority class should be used.
  // +optional
  optional string description = 4;

  // preemptionPolicy is the Policy for preempting pods with lower priority.
  // One of Never, PreemptLowerPriority.

- [Creating Fast and Lean Code](https://github.com/istio/istio/wiki/Writing-Fast-and-Lean-Code) - performance-oriented advice and guidelines for the code base

You'll find many other useful documents on our [Wiki](https://github.com/istio/istio/wiki).

## Introduction