# Immutable Data Over Mutable State

> Replace in-place mutation with a pure transform returning new data, so state transitions are reproducible.

Record: `algorithms:no-mutable`
Kind: algorithm
Canonical: https://banes-lab.com/ontology/algorithms#algorithms-no-mutable
Closure: https://banes-lab.com/json/records/algorithms/no-mutable/closure

Listed in [Algorithm contracts](https://banes-lab.com/api/records/algorithms.md), after [Structural Release Over Discipline](https://banes-lab.com/records/algorithms/no-discipline-release.md) and before [Errors As Language Over Silent Errors](https://banes-lab.com/records/algorithms/no-silent.md).

## Domain

- [Architectural Rules](https://banes-lab.com/records/algorithms-domain/architectural-rules.md)

## Tier

- [leaf](https://banes-lab.com/records/vocabulary/domain-tier-leaf.md)

## Composes

- [Computation Core](https://banes-lab.com/records/algorithms/computation-core.md)

## Math type

- [Logic](https://banes-lab.com/records/reasoning/math-type-logic.md)

## Linked from

- [Architectural Clusters](https://banes-lab.com/ontology/algorithms/algorithms-domain-architectural-clusters.md)
- [The mathematics](https://banes-lab.com/ontology/reasoning/the-mathematics.md)
- [Domain tiers](https://banes-lab.com/ontology/schema/the-vocabulary-domain-tier.md)