Override rules

Override rules let you return different config values based on context. Use them for:

• User targeting (specific users or segments)
• A/B testing (different variants)
• Regional configuration (different values per region)
• Gradual rollouts (percentage-based)

How overrides work

1. Your app passes context: { userId: "123", plan: "premium" }
2. Replane evaluates overrides in order
3. First matching override's value is returned
4. If no override matches, base value is returned

Context: { plan: "premium" }
                │
                ▼
┌─────────────────────────────┐
│ Override 1: plan === "free" │ ──── No match
└─────────────────────────────┘
                │
                ▼
┌─────────────────────────────────┐
│ Override 2: plan === "premium"  │ ──── Match! Return override value
└─────────────────────────────────┘
                │
                ▼
        (stops here)

Create an override

1. Click on a config in the dashboard
2. Click Add Conditional Override
3. Configure:
   • Name: Human-readable description
   • Conditions: Rules that must all match
   • Value: What to return when conditions match
4. Click Save

Condition types

Equals

Exact match on a context property.

Example: Enable for premium users

plan equals "premium"

replane.get('feature', { context: { plan: 'premium' } }); // matches
replane.get('feature', { context: { plan: 'free' } }); // no match

In / Not in

Check if value is in (or not in) a list.

Example: Enable for US and Canada

country in ["US", "CA"]

replane.get('feature', { context: { country: 'US' } }); // matches
replane.get('feature', { context: { country: 'UK' } }); // no match

Numeric comparisons

Compare numbers with <, <=, >, >=.

Example: Enable for users with 10+ purchases

purchaseCount >= 10

replane.get('feature', { context: { purchaseCount: 15 } }); // matches
replane.get('feature', { context: { purchaseCount: 5 } }); // no match

Percentage

Enable for a percentage of users based on a bucketing key.

Example: Enable for 25% of users

25% of userId

// Some users will match, others won't (deterministic per userId)
replane.get('feature', { context: { userId: 'user-123' } });

The same user always gets the same result.

Multiple conditions

All conditions in an override must match (AND logic).

Example: Premium users in the US

plan equals "premium"
AND
country equals "US"

// Must match both conditions
replane.get('feature', {
  context: { plan: 'premium', country: 'US' }
}); // matches

replane.get('feature', {
  context: { plan: 'premium', country: 'UK' }
}); // no match (wrong country)

Override priority

Overrides are evaluated in order. First match wins.

Example configuration:

Priority	Override	Condition	Value
1	VIP users	userId in ["vip-1", "vip-2"]	"vip"
2	Premium	plan === "premium"	"premium"
3	Free	plan === "free"	"free"
—	Base	(none)	"default"

// VIP user with premium plan → "vip" (first match)
replane.get('feature', {
  context: { userId: 'vip-1', plan: 'premium' }
});

// Regular premium user → "premium"
replane.get('feature', {
  context: { userId: 'user-123', plan: 'premium' }
});

Drag and drop overrides in the dashboard to reorder them.

Context best practices

Common context properties

Property	Type	Use case
userId	string	User targeting, percentage rollouts
plan	string	Subscription tier features
country	string	Regional configuration
region	string	Infrastructure region
deviceType	string	Mobile vs desktop features
appVersion	string	Version-specific behavior
env	string	Environment-specific values

Set default context

Configure context at the client level:

import { Replane } from '@replanejs/sdk'

const replane = new Replane({
  context: {
    region: 'us-east',
    userId: 'user-123'
  }
})
await replane.connect({
  sdkKey: process.env.REPLANE_SDK_KEY!,
  baseUrl: 'https://replane.example.com'
})

// Every get() call includes env and region
const value = replane.get('config-name');

Merge context per request

Override or extend client context:

// Merges with client context
const value = replane.get('config-name', {
  context: {
    userId: user.id,
    plan: user.plan
  }
});

Examples

Premium features

Config: advanced-analytics
Base value: false

Override: Premium users
  Condition: plan equals "premium"
  Value: true

Regional pricing

Config: pricing-tier
Base value: "standard"

Override: EU region
  Condition: region in ["eu-west", "eu-central"]
  Value: "eu"

Override: APAC region
  Condition: region in ["ap-south", "ap-northeast"]
  Value: "apac"

Beta program

Config: feature-new-editor
Base value: false

Override: Beta users
  Condition: userFlags contains "beta"
  Value: true

Override: Internal team
  Condition: email endsWith "@company.com"
  Value: true

Debugging overrides

Check which override matched:

1. Open the config in the dashboard
2. Use the Evaluate panel
3. Enter test context values
4. See which override matches and the returned value

Next steps

• Gradual Rollouts — Percentage-based releases
• Feature Flags — Toggle features
• JavaScript SDK — Full API reference