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Priority-Based Targeting

Priority-based targeting gives you precise control over the order in which targeting rules are evaluated, ensuring the right users get the right experience.

What is Priority-Based Targeting?

Targeting rules (criteria) are evaluated in order based on their priority value:

  • Lower priority numbers are evaluated first
  • First matching rule determines the outcome
  • Enables complex targeting scenarios with predictable results

Why Order Matters

Without priority control, rule evaluation order is unpredictable. With priorities, you can ensure:

  • Premium users always get premium features
  • Regional rules override global defaults
  • Specific segments get targeted experiences before falling back to defaults

Example Scenario

Without Priority:

Rule A: Beta users → enabled (100%)
Rule B: Premium users → variant-premium

Problem: Premium users who are also beta users might match either rule randomly.

With Priority:

Priority 0: Premium users → variant-premium (100%)
Priority 1: Beta users → enabled (100%)

Result: Premium users always match first, even if they're also in beta program.

How to Use Priorities

Setting Priorities in the UI

Visual Drag-and-Drop

  1. Navigate to your feature
  2. Go to the environment's targeting rules
  3. Drag and drop rules to reorder them
  4. Rules at the top have lower priority (evaluated first)
  5. Rules at the bottom have higher priority (evaluated last)

Manual Priority Assignment

  1. Click Edit on a targeting rule
  2. Set the Priority field (0, 1, 2, etc.)
  3. Lower numbers = higher priority (evaluated first)
  4. Click Save

Default Behavior

  • New rules automatically get the next available priority number
  • Existing rules maintain their relative order when adding new ones

Common Priority Patterns

1. Layered Targeting

Serve different variants to overlapping user segments.

Priority 0: Enterprise customers → premium-features (100%)
Priority 1: Team plan users → standard-features (100%)
Priority 2: Individual users → basic-features (50%)
Priority 3: Everyone else → disabled

Why it works: Enterprise customers get premium features even if they also match "Team plan" criteria.

2. Geographic Rollout

Roll out features by region with fallback.

Priority 0: region=US → enabled (100%)
Priority 1: region=EU → enabled (75%)
Priority 2: region=APAC → enabled (50%)
Priority 3: All others → enabled (10%)

Why it works: US users always get the feature, other regions have gradual rollouts.

3. VIP Treatment

Ensure VIPs always get special treatment.

Priority 0: userId in VIP_LIST → variant-vip (100%)
Priority 1: tier=premium → variant-premium (100%)
Priority 2: tier=standard → variant-standard (50%)
Priority 3: Everyone else → control (10%)

Why it works: VIP users get special variant regardless of their tier.

4. Feature Gates with Override

Allow manual overrides for specific users.

Priority 0: userId in BETA_TESTERS → enabled (100%)
Priority 1: tier=enterprise → enabled (50%)
Priority 2: All others → disabled

Why it works: Beta testers always get access, even if they don't have enterprise tier.

5. A/B Test with Control Group

Run experiments while excluding certain users.

Priority 0: userId in EXCLUSION_LIST → disabled
Priority 1: region=US → variant-a (33%), variant-b (33%), control (34%)
Priority 2: All others → disabled

Why it works: Excluded users never participate in the test.

Best Practices

1. Start with Specific, End with General

Place most specific rules at lower priority numbers (top), general rules at higher numbers (bottom).

✅ Good:
Priority 0: userId=specific-user → variant-a
Priority 1: tier=premium → variant-b
Priority 2: All users → control

❌ Bad:
Priority 0: All users → control
Priority 1: tier=premium → variant-b  // Never evaluated!
Priority 2: userId=specific-user → variant-a  // Never evaluated!

2. Use Priority Gaps

Leave gaps between priority numbers for future insertions.

✅ Good: 0, 10, 20, 30 (can insert 15 between 10 and 20)
❌ OK but limiting: 0, 1, 2, 3

3. Document Rule Purpose

Add clear descriptions to each rule explaining why it has that priority.

4. Test Priority Changes

After reordering rules, test with sample user contexts to verify expected behavior.

5. Review Regularly

Periodically review priority order to ensure it still matches your business logic.

Visual Priority Management

FluxGate's UI makes priority management intuitive:

Drag-and-Drop Interface

  • Grab the handle icon on the left of each rule
  • Drag up or down to reorder
  • Drop in the desired position
  • Priority numbers update automatically

Visual Indicators

  • Rules are displayed in evaluation order (top to bottom)
  • Priority numbers are shown for reference
  • First matching rule is highlighted during simulation

Real-Time Updates

  • Changes propagate to edge servers immediately
  • No deployment required
  • Users see updated behavior within seconds

Evaluation Flow

When evaluating a feature for a user:

  1. Sort Rules: All targeting rules sorted by priority (ascending)
  2. Iterate: Check each rule in order
  3. Match Test: Does user's context match rule conditions?
  4. First Match: If yes, return the result (variant or boolean)
  5. Stop: Evaluation stops, remaining rules ignored
  6. No Match: If no rules match, feature is disabled

Troubleshooting

Rule Never Matches

Symptom: Rule appears correct but never returns expected result.

Possible causes:

  • Higher priority rule matches first
  • User context doesn't actually match conditions
  • Rollout percentage excludes this user

Solution:

  1. Check rules with lower priority numbers
  2. Verify user context values
  3. Test with 100% rollout to eliminate percentage issues

Wrong Variant Served

Symptom: User gets unexpected variant.

Possible causes:

  • Higher priority rule specifies different variant
  • Multiple rules match, first one wins

Solution:

  1. Review all rules with priority < current rule
  2. Ensure only intended rule matches user
  3. Adjust priorities if needed

Can't Reorder Rules

Symptom: Drag-and-drop doesn't work.

Solution:

  • Ensure you're in edit mode
  • Check browser console for errors
  • Refresh page and try again
  • Use manual priority field as fallback

Advanced Scenarios

Gradual Migration

Migrate users from old to new experience gradually.

Priority 0: rollout_group=early_adopters → new_experience (100%)
Priority 1: Random 25% → new_experience (25%)
Priority 2: Everyone else → old_experience

Over time, increase Priority 1 rollout: 25% → 50% → 75% → 100%

Canary Release by Region

Test in one region before expanding.

Week 1:
Priority 0: region=US-WEST → new_version (10%)
Priority 1: All others → old_version

Week 2:
Priority 0: region=US-WEST → new_version (50%)
Priority 1: region=US-EAST → new_version (10%)
Priority 2: All others → old_version

Persona-Based Variants

Serve different experiences to different user personas.

Priority 0: persona=developer → dev_focused_ui
Priority 1: persona=designer → design_focused_ui
Priority 2: persona=manager → analytics_focused_ui
Priority 3: Everyone else → default_ui

Related Topics