# Assumed Single Writer

> A defect in which the one-writer invariant is assumed to cover a jointly authored surface.

Record: `lexicon:assumed-single-writer`
Kind: anti-pattern
Layer: [Execution Core](https://banes-lab.com/records/layer/execution-core.md)
Canonical: https://banes-lab.com/ontology/lexicon#lexicon-assumed-single-writer

Listed in [Lexicon terms](https://banes-lab.com/api/records/lexicon.md), after [Whole-Surface Rewrite](https://banes-lab.com/records/lexicon/whole-surface-rewrite.md) and before [Fenced Joint Surface](https://banes-lab.com/records/lexicon/fenced-joint-surface.md).

## Category

- [Coordination Surfaces](https://banes-lab.com/records/lexicon-category/coordination-surfaces.md)

## Violates

- [Operand-Free Outcome Surface](https://banes-lab.com/records/architecture/operand-free-outcome-surface.md)

## Linked from

- [Coordination Surfaces](https://banes-lab.com/ontology/principles/architecture-category-coordination-surfaces.md)