Rule Engine

Declarative form validation with composable rules and JSON schemas

Validate appsettings.json configuration sections at startup with attribute-based rules.

Validate credit card numbers with Luhn check, detect card brand, and mask for display.

RFC 5321/5322 compliant email validation with typo suggestions, disposable email detection, and bulk validation.

Declarative environment variable validation for .NET — attribute-based binding with type coercion.

Lightweight feature flags with percentage rollout, user targeting, time-based scheduling, and analytics — no external service required.

International phone number validation and formatting based on ITU-T E.164 with country detection.

Struct-based environment variable validation with batch error reporting for Go

Lightweight feature flags for Go with toggles, percentage rollouts, user targeting, and A/B variants

Declarative environment variable validation and typed loading for Kotlin.

Local feature flag evaluation with percentage rollouts, user targeting, time-based flags, and composable rules.

Fluent guard clause validation for Kotlin with descriptive error messages.

Declarative data validation with composable rules and structured errors.

Validate required environment variables with type checking and defaults

Lightweight feature flags with config and database drivers, percentage rollout, and scheduling

Lightweight business rule engine with declarative conditions and actions

Fluent data schema validator with nested objects, arrays, and dot-notation errors

Schema-based environment variable validation with type coercion and helpful error messages.

Simple feature flags with percentage rollout and user targeting.

Configuration schema validator with type checking and helpful error messages

RFC-compliant email validation with MX record verification, disposable domain detection, normalization, and typo suggestions

Schema-based environment variable validation with typed accessors

Minimal feature flag system with YAML, ENV, and in-memory backends

Expressive guard clause DSL for method precondition validation

Lightweight rule engine with declarative conditions and actions

Lightweight schema validation for hashes with type coercion

Typed environment variable validation with batch error reporting for Rust

In-memory feature flag evaluation with rollout, environment, targeting, and A/B variant support for Rust

Early-return guard clause macros for cleaner control flow

Type-safe feature flags with local defaults, remote overrides, and SwiftUI integration

Schema-based environment variable validation with type-safe accessors

Simple in-memory feature flag system with percentage rollouts and targeting