Defining Segments

Segments group customers based on rules and attributes. Define segments in your config to create rule-based customer groups that can be used for content targeting, experiments, and analytics.

Segment Interface


interface ApplyConfigSegmentInput {
  key: string;                          // Unique identifier (e.g., 'vip-customers')
  name: string;                         // Display name
  description?: string;                 // What this segment represents
  rules?: Record<string, unknown>;      // Matching rules
  evaluationMode?: string;              // 'realtime' or 'batch'
  isActive?: boolean;                   // Whether the segment is evaluating (default: true)
}

Basic Example


import { defineConfig, defineSegment } from '@eide/foir-cli/configs';
 
export default defineConfig({
  key: 'my-app',
  name: 'My App',
  segments: [
    defineSegment({
      key: 'vip-customers',
      name: 'VIP Customers',
      description: 'Customers with total spend over $500',
      rules: {
        type: 'condition',
        left: { type: 'field', path: 'totalSpend' },
        operator: 'greaterThan',
        right: { type: 'literal', value: 500 },
      },
      isActive: true,
    }),
  ],
});

Rules Structure

Segment rules use a condition expression format. Each rule specifies a left operand, an operator, and a right operand.

Simple Condition


rules: {
  type: 'condition',
  left: { type: 'field', path: 'orderCount' },
  operator: 'greaterThan',
  right: { type: 'literal', value: 5 },
}

Combining Conditions

Use and or or to combine multiple conditions:


rules: {
  type: 'and',
  conditions: [
    {
      type: 'condition',
      left: { type: 'field', path: 'totalSpend' },
      operator: 'greaterThan',
      right: { type: 'literal', value: 500 },
    },
    {
      type: 'condition',
      left: { type: 'field', path: 'orderCount' },
      operator: 'greaterThan',
      right: { type: 'literal', value: 5 },
    },
  ],
}

Available Operators

Operator	Description
`equals`	Exact match
`notEquals`	Does not match
`greaterThan`	Greater than a value
`lessThan`	Less than a value
`greaterThanOrEqual`	Greater than or equal
`lessThanOrEqual`	Less than or equal
`contains`	String contains value
`startsWith`	String starts with value
`in`	Value is in a list
`notIn`	Value is not in a list

Evaluation Modes

Mode	Description	Use Case
`realtime`	Evaluated on every content request	Targeting rules that need instant accuracy
`batch`	Evaluated periodically in the background	Large segments where slight delay is acceptable


segments: [
  {
    key: 'high-value',
    name: 'High Value',
    evaluationMode: 'realtime',
    rules: { ... },
  },
  {
    key: 'inactive-users',
    name: 'Inactive Users',
    evaluationMode: 'batch',
    rules: { ... },
  },
]

Examples

Mobile Users


defineSegment({
  key: 'mobile-users',
  name: 'Mobile Users',
  description: 'Customers who primarily use mobile devices',
  rules: {
    type: 'condition',
    left: { type: 'field', path: 'primaryDevice' },
    operator: 'equals',
    right: { type: 'literal', value: 'mobile' },
  },
  evaluationMode: 'realtime',
  isActive: true,
})

High-Spend Repeat Buyers


defineSegment({
  key: 'high-spend-repeat',
  name: 'High-Spend Repeat Buyers',
  description: 'Customers with 10+ orders and over $1000 total spend',
  rules: {
    type: 'and',
    conditions: [
      {
        type: 'condition',
        left: { type: 'field', path: 'totalSpend' },
        operator: 'greaterThan',
        right: { type: 'literal', value: 1000 },
      },
      {
        type: 'condition',
        left: { type: 'field', path: 'orderCount' },
        operator: 'greaterThanOrEqual',
        right: { type: 'literal', value: 10 },
      },
    ],
  },
  isActive: true,
})

Regional Segment


defineSegment({
  key: 'eu-customers',
  name: 'EU Customers',
  description: 'Customers in European markets',
  rules: {
    type: 'condition',
    left: { type: 'field', path: 'market' },
    operator: 'in',
    right: { type: 'literal', value: ['uk', 'de', 'fr', 'es', 'it', 'nl'] },
  },
  evaluationMode: 'batch',
  isActive: true,
})

Next Steps

Segments Concepts — How segments work, evaluation, and membership
Targeting — Use segments in variant targeting rules
Configuration Reference — Full config API reference