# Summary

[Introduction](./ch00/s00-introduction.md)

- [Background](./ch01/s00-background.md)
- [Implementation](./ch02/s00-implementation.md)
- [Usage]()
- [Current Implementation Concerns](./ch04/s00-concerns.md)
  - [Alternative Monad Traits](./ch04/s01-alternatives.md)
  - [Lifetimes](./ch04/s02-lifetimes.md)
  - [Stackless](./ch04/s03-stackless.md)
  - [Covariance](./ch04/s04-covariance.md)