Module types 

Core Binding Types

Foundational types for the binding system redesign:

• BindingPath: Parsed path like $step1.data.items[0].name
• BindingSource: Where data comes from (Task, Context, Input, Env, LoopVar)
• PathSegment: Individual path segment (field name or array index)
• BindingType: Type constraint on binding values (7 variants)

Path Syntax

All binding paths start with $:

Pattern	Source	Example
$task_id	Task output	$step1, $step1.data.name
$context.*	Context file/session	$context.files.brand
$inputs.*	Workflow inputs	$inputs.locale
$env.*	Environment variable	$env.API_URL
$item	Loop variable (for_each)	$item, $item.name

Array indexing uses brackets: $data.items[0].name

Design Notes

• Arc<str> for identifiers: cheap clones, no lifetime issues
• BindingPath is Hash + Eq for use as map keys
• BindingType has serde support for YAML deserialization
• Parse errors use NIKA-150 error code

Structs

BindingPath

Source path for a binding – parsed from “$task_id.field.path”

BindingPathError

Error type for binding path parsing (NIKA-150)

Enums

BindingSource

Where data originates

BindingType

Type constraint on a binding value (optional, defaults to Any)

PathSegment

Single segment in a property path