Real-time blocking
Rules execute in milliseconds to block inline without noticeable delay.
Run velocity-based rules in real-time
Flexibility
Run flexible velocity rules in real-time
Castle's no-code rules engine takes real-time action against abuse, returning in milliseconds even as conditions get more complex.
Super fast inline API responses in under 150 ms
Lightning-fast rule execution that doesn't impact user experience with sub-150ms response times.
Aggregate velocity metrics with zero latency
Real-time computation of velocity queries across fields and time ranges without delays.
Advanced querying logic on any custom data
Build complex rules using your custom properties and business-specific data points.
Automation
Alert and automate at scale
Use webhooks, Slack alerts, and Lists to automate abuse prevention at any scale. Notify your team of attack spikes and suspicious logins.
Alert your team on Slack in real-time when rules trigger
Instant Slack notifications keep your team informed of rule activations and emerging threats.
Use webhooks to trigger custom logic in your app
Trigger custom workflows and integrations in your application when rules are activated.
Add device fingerprints, users, IPs, and others to lists
Automatically populate Castle Lists with entities that trigger rules for ongoing protection.
Simulation
Simulate complex logic instantly
See the impact of rule changes immediately. Iterate faster, then deploy with confidence that you will not block legitimate users.
Create rules with just one click from any query
Turn any exploratory query into an actionable rule instantly without complex configuration.
Lightning-fast backtesting of velocity queries
Test your rules against historical data in seconds to validate behavior before deployment.
Use heatmaps to set balanced thresholds for your rules
Visualize data distributions to find the optimal thresholds that catch abuse without false positives.
Get started
Create your free account today
Start with a free quota, with transparent pricing that scales when you do.