---
title: "Flow"
description: "a kind of flow, as a row of the register: the only way a unit changes place or a new unit is made"
section: concepts
address: /concepts/flow
contract: 0476e35e6e275db5
---

# Flow

a kind of flow, as a row of the register: the only way a unit changes place or a new unit is made

[figure: Flow is a row at platform scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | row |
| scope | platform |
| key | its name |
| store | postgres |
| family | kernel |



## Fields


| field | type | required | note |
|---|---|---|---|
| `name` | `text` | yes |  |
| `meaning` | `text` | yes |  |
| `unit_kind` | [Kind](/concepts/kind) | yes |  |
| `from_place` | `text` | no |  |
| `to_place` | `text` | no |  |
| `makes_kind` | [Kind](/concepts/kind) | no | for a flow that makes a fact |
| `emitted_by` | `text` | yes | the one part that emits it |
| `plane` | `one of tenant plane \| work plane` | yes |  |
| `version_of_shape` | `count` | yes |  |
| `repeat_rule` | `text` | yes | what makes a repeat harmless |
| `retention_class` | [RetentionClass](/concepts/retentionclass) | yes |  |
| `reasons` | `[text]` | yes | the typed reasons its outcomes may carry, each with its failure class |



## Routes that use it
No route takes or returns Flow directly. The record holds it, and the objects that point at it reach it.