Run velocity-based rules in real-time
Real-time blocking
Rules execute in milliseconds to block inline without noticeable delay.
Zero-lag velocities
Advanced aggregations over any field and time range at blazing speed.
Alerts & automation
Trigger webhooks, Slack notifications, or put entities into custom lists.
Instant simulation
Quickly backtest and tweak policies to deploy with confidence.
Run flexible velocity rules in real-time
Castle's no-code rules engine empowers you to proactively prevent abuse by taking real-time action. Even as trigger conditions become more complex, it returns responses in milliseconds, ensuring seamless performance.
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.
Alert and automate at scale
Implement webhooks, Slack alerts, or leverage the versatile Lists feature to automate abuse prevention in your application, regardless of its size. Keep your team notified about spikes in attacks, alert end-users of suspicious login attempts, and streamline user reviews.
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.
Simulate complex logic instantly
Experience the power of rule logic tweaking: see immediate impact, speed up iteration and experimentation, and gain the confidence to deploy rules seamlessly without unintentionally blocking 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.
Create your free account today
Starting at $0 for 1,000 requests per month, with transparent pricing that scales with your needs.