Top Enterprise AI Gateways to Implement Guardrails and Security for Your GenAI Apps

TL;DR

AI gateways have become essential infrastructure for deploying GenAI applications safely. They enforce content moderation, PII protection, access controls, and compliance policies at the infrastructure layer, between your apps and LLM providers. This article compares five leading platforms: Bifrost, Cloudflare AI Gateway, Kong AI Gateway, NVIDIA NeMo Guardrails, and Guardrails AI.

Why Guardrails Belong at the Gateway Layer

LLMs are non-deterministic. You cannot control what users ask, and you have limited control over what models respond. Without proper guardrails, a single mishandled prompt can leak sensitive data, produce harmful content, or violate regulatory requirements. Gartner predicts that by 2028, more than half of enterprises will deploy an AI security platform to enforce consistent guardrails across all AI applications.

The most reliable approach is enforcing these guardrails at the gateway layer, where every request and response is intercepted and governed without modifying application code.

1. Bifrost by Maxim AI

Platform Overview

Bifrost is a high-performance, open-source AI gateway built in Go by Maxim AI. It combines near-zero latency overhead with one of the most comprehensive guardrail and governance stacks available today. Public benchmarks show approximately 11 microseconds of overhead at 5,000 RPS, meaning security layers add virtually no performance cost.

Bifrost supports 12+ providers (OpenAI, Anthropic, AWS Bedrock, Google Vertex, Azure, and more) through a single OpenAI-compatible API, and deploys in seconds via NPX or Docker as a drop-in replacement with a one-line code change.

Key Guardrail and Security Features

• Real-time response blocking: Detects and blocks unsafe outputs instantly using configurable moderation and policy rules through the guardrails engine.
• Infrastructure-level governance: Enforces rate limits, usage tracking, and fine-grained access controls on every request with virtual keys for isolated environments.
• Hierarchical budget controls: Set spending limits across organizations, teams, and customers via budget management to prevent runaway costs.
• MCP tool governance: Restricts which tools AI agents can invoke through Model Context Protocol controls, adding a critical security layer for agentic workflows.
• RBAC with SSO and Vault: Granular permissions with SAML-based SSO, audit logging, and HashiCorp Vault integration for secure key management.
• Custom plugin system: Inject organization-specific guardrail logic as middleware through custom plugins.
• Full observability: Native OpenTelemetry support, distributed tracing, Prometheus metrics, and log exports for compliance.

What makes Bifrost especially compelling is its integration with Maxim's evaluation and observability platform. Gateway-level guardrails catch issues in real time, while Maxim's evaluation workflows help teams identify and fix root causes of unsafe outputs, creating a closed loop between runtime protection and continuous improvement.

Best For

Teams running production AI systems that need strict safety guarantees, deep governance, and minimal latency, especially when paired with evaluation and observability workflows. The enterprise tier includes SOC 2 Type II compliance, in-VPC deployments, and private networking for regulated industries.

2. Cloudflare AI Gateway

Platform Overview

Cloudflare AI Gateway extends Cloudflare's global edge network to AI traffic, providing content moderation and observability for LLM applications.

Key Features

• Built-in guardrails powered by Llama Guard with configurable block, flag, or allow actions across risk categories.
• DLP scanning to block PII and sensitive financial data from reaching LLMs.
• Dynamic routing for rate limiting, A/B testing, and model chaining.

Best For

Teams already on Cloudflare that want globally distributed content moderation with minimal setup.

3. Kong AI Gateway

Platform Overview

Kong AI Gateway extends Kong's mature API management platform to AI traffic with a plugin-based approach to guardrails.

Key Features

• AI Prompt Guard plugin for semantic allow/deny topic lists enforced at the gateway layer.
• PII sanitization across 20 categories and 9 languages, with options to redact or tokenize.
• MCP proxy support with OAuth 2.1 and tool-level access control.

Best For

Enterprises already running Kong for API management that want unified governance across APIs and AI workloads.

4. NVIDIA NeMo Guardrails

Platform Overview

NVIDIA NeMo Guardrails is an open-source toolkit for building programmable safety policies for LLM applications.

Key Features

• Programmable policies for content moderation, PII detection, topic relevance, and jailbreak prevention.
• Multi-rail orchestration evaluating up to five guardrails in parallel with roughly 0.5 seconds of latency.
• GPU-accelerated inference through NemoGuard NIM microservices.

Best For

Teams with NVIDIA GPU infrastructure that need deep customization over guardrail logic.

5. Guardrails AI

Platform Overview

Guardrails AI is a specialized platform for validating and enforcing safety policies on LLM inputs and outputs with pre-built validators.

Key Features

• Real-time hallucination detection for catching inaccurate outputs before they reach users.
• PII guardrails for blocking sensitive data exposure.
• AI agent reliability tooling that improves execution success rates for agentic workflows.

Best For

Teams that need a dedicated, modular safety layer to integrate with their existing AI infrastructure.

Choosing the Right Gateway

For comprehensive guardrails with top performance and evaluation integration, Bifrost stands out by connecting runtime protection directly to Maxim's observability and evaluation platform. Cloudflare suits teams already on their ecosystem. Kong is natural for enterprises with existing API management. NeMo Guardrails and Guardrails AI serve teams needing specialized, deeply customizable safety logic.

Regardless of which platform you choose, enforcing guardrails at the infrastructure layer is the most reliable way to scale AI safely.

Get started with Bifrost in under a minute, or book a demo to explore the full Maxim platform.