Open Source API Gateways 2026: Kong vs Envoy vs APISIX
The open-source API gateway landscape in 2026 includes Kong, Envoy, APISIX, Tyk, Gravitee, and STOA. This guide compares their architectures, MCP support, multi-tenancy, and licensing — with a focus on AI-readiness and European sovereignty.
The open source API gateway landscape in 2026 looks very different from what it was just two years ago. The rise of AI agents, the Model Context Protocol (MCP), and stricter European regulations have reshaped what organizations expect from their API infrastructure. This article provides an honest comparison of the leading open-source gateways and where each one excels.
Choosing an API gateway is one of the most consequential infrastructure decisions a platform team will make. The gateway touches every request, enforces every policy, and often outlives the applications it serves. Making the right choice requires understanding not just today's requirements but where the ecosystem is heading.
The 2026 Open Source Gateway Landscape
Five open-source API gateways dominate the conversation in 2026. Each has a different origin story, architecture, and sweet spot.
Kong Gateway
Kong remains the most widely deployed open-source API gateway. Built on OpenResty (Nginx + Lua), it has a mature plugin ecosystem and strong community. Kong's commercial offering (Kong Enterprise / Konnect) adds a management plane, developer portal, and enterprise support.
Strengths: Mature ecosystem, large plugin library, proven at scale, strong commercial backing. Weaknesses: Lua-based plugin model can be a barrier for teams without Lua expertise. The open-source version lacks multi-tenancy and a developer portal. The gap between OSS and Enterprise features has widened over time. MCP support is plugin-based (AI MCP Proxy, MCP OAuth2) rather than core architecture.
Envoy Proxy
Envoy is not a traditional API gateway — it is a programmable proxy that serves as the data plane for service meshes like Istio. However, projects like Envoy Gateway (the Kubernetes Gateway API implementation) have made it increasingly viable as a standalone API gateway.
Strengths: Extremely high performance (C++), extensible via WASM filters, first-class Kubernetes integration, strong observability, CNCF graduated project. Weaknesses: Not a batteries-included API management platform. Requires additional tooling for developer portal, subscription management, and policy orchestration. Configuration complexity is significant for teams new to the ecosystem.
Apache APISIX
APISIX is a high-performance gateway built on Nginx and etcd, originating from the Chinese open-source community. It offers a rich plugin system and a dashboard for configuration management.
Strengths: High performance, active development, good plugin ecosystem, full Apache 2.0 license, etcd-based configuration is highly available. Weaknesses: Smaller community outside Asia-Pacific. Documentation quality can be inconsistent. Enterprise features and commercial support are less mature than Kong's offering.
Tyk Gateway
Tyk is written in Go and provides a full API management stack in its open-source edition, including a dashboard and developer portal. It is one of the few gateways that offers multi-tenancy in the open-source version.
Strengths: Full management stack in OSS, Go-based (easy to extend), built-in analytics, multi-tenancy support. Weaknesses: Smaller community and ecosystem compared to Kong and Envoy. Performance under extreme load trails C++ and Nginx-based alternatives. GraphQL federation support is still maturing.
STOA Platform
STOA is the newest entrant, purpose-built for the AI era. It combines a Rust-based data plane with a Python/FastAPI control plane, and is the first open-source gateway to include native MCP (Model Context Protocol) support. STOA follows a hybrid Control Plane / Data Plane architecture designed for European data sovereignty requirements.
Strengths: Native MCP support, multi-tenant by design, hybrid deployment (control plane cloud + data plane on-premise), full management stack (console, portal, API), European compliance focus (DORA, NIS2, GDPR). For more details, see the API gateway patterns documentation. Weaknesses: Youngest project with the smallest community. Plugin ecosystem is still growing. Production deployments are in early stages compared to Kong and Envoy.
Feature Comparison Table
| Feature | Kong OSS | Envoy | APISIX | Tyk OSS | STOA |
|---|---|---|---|---|---|
| License | Apache 2.0 | Apache 2.0 | Apache 2.0 | MPL 2.0 | Apache 2.0 |
| Language | Lua / Go | C++ | Lua / Go | Go | Rust / Python |
| MCP Support | Plugin (since 3.12, Enterprise only) | No | No | No | Native (core) |
| Multi-Tenancy (OSS) | No | No | No | Yes | Yes |
| Developer Portal (OSS) | No | No | No | Yes | Yes |
| Admin Console (OSS) | No | No | Dashboard | Yes | Yes |
| Kubernetes Native | Ingress Controller | Gateway API | Ingress Controller | Operator | CRDs + Operator |
| Policy Engine | Plugins | WASM / ext_authz | Plugins | Middleware | OPA (native) |
| Service Mesh | Kong Mesh (Envoy-based) | Istio / native | No | No | No |
| Protocol Support | REST, gRPC, GraphQL, WebSocket | REST, gRPC, HTTP/3, TCP | REST, gRPC, GraphQL, Dubbo | REST, gRPC, GraphQL, TCP | REST, MCP, gRPC |
| Observability | Plugins | Native (rich) | Plugins | Built-in | OpenSearch + Grafana |
| Hybrid Deploy | Enterprise only | N/A | Partial | Enterprise only | Native (OSS) |
| EU Compliance Focus | No | No | No | No | Yes (DORA, NIS2) |
The AI-Native Dimension
The most significant differentiator in 2026 is not performance or plugin count — it is AI agent support. As enterprises deploy AI agents (built on Claude, GPT, Gemini, and open-source models), these agents need secure, governed access to enterprise tools and data.
The Model Context Protocol (MCP) has emerged as the standard for AI agent-to-tool communication. Kong has moved fastest among incumbents, adding MCP proxy and OAuth2 plugins in Gateway 3.12, with MCP ACLs and guardrails following in 3.13. But there is a meaningful architectural difference between adding MCP support as plugins on an HTTP proxy and building a gateway where MCP is a core protocol alongside REST.
Why MCP Matters for Gateways
MCP introduces new requirements that traditional API gateways were not designed for:
- Tool discovery — AI agents need to discover available tools dynamically, not hardcode endpoints.
- Streaming responses — MCP supports Server-Sent Events (SSE) for real-time tool execution feedback.
- Structured tool calls — MCP defines a JSON-RPC-based protocol for invoking tools with typed parameters.
- Session management — AI agent sessions span multiple tool calls and require state tracking.
- Token optimization — Tool descriptions must be compressed and cached to minimize LLM token usage.
The plugin approach works for bridging MCP-to-HTTP traffic. But deeper capabilities — CRD-based tool governance, per-tenant tool filtering, UAC "define once, expose as REST + MCP + GraphQL", and legacy gateway orchestration — require MCP to be a foundational protocol, not an adapter layer.
Where Each Gateway Excels
Rather than declaring a single winner, here is where each gateway genuinely shines:
Choose Kong When...
- You need a battle-tested gateway with the largest ecosystem of plugins.
- Your team has experience with Nginx and Lua.
- You are willing to invest in Kong Enterprise for management features.
- Kong's plugin-based MCP support (AI MCP Proxy, MCP OAuth2, MCP ACLs) is sufficient for your AI use case.
Choose Envoy When...
- Performance is your top priority and you need L4/L7 proxy capabilities.
- You are building a service mesh or already use Istio.
- Your team can handle WASM filter development.
- You plan to build custom management tooling on top.
Choose APISIX When...
- You want a high-performance gateway with a permissive Apache 2.0 license.
- You prefer etcd-based configuration management.
- Your team is comfortable with the Apache ecosystem.
Choose Tyk When...
- You need a full API management stack (gateway + portal + analytics) in open source.
- You prefer Go for extensibility.
- Multi-tenancy in the free tier matters to you.
Choose STOA When...
- You are connecting AI agents to enterprise APIs and need native MCP support.
- Multi-tenancy and hybrid deployment are requirements, not nice-to-haves.
- European regulatory compliance (DORA, NIS2, GDPR) is a concern.
- You want a full management stack (console, portal, API) under Apache 2.0.
- You are building for the next five years, not the last five.
The Convergence Ahead
Kong has already added MCP support, and we expect APISIX and Envoy (via WASM filters) to follow. The question going forward is not "does your gateway support MCP?" but "how deeply is MCP integrated into your gateway's architecture?" — and whether your gateway can orchestrate existing legacy gateways alongside AI traffic.
Similarly, multi-tenancy and developer portals are becoming table stakes. The trend is clear: open-source gateways are evolving from traffic proxies into full API management platforms.
Try STOA
If your use case involves AI agents, multi-tenancy, or European compliance, STOA is worth evaluating alongside the established alternatives.
- Read the Architecture documentation
- Explore API Gateway Patterns
- Get started with the Quickstart Guide
- Join the conversation on GitHub and Discord
Further Reading
- Complete API Gateway Migration Guide 2026 — Decision framework for legacy gateway modernization
- API Gateway Patterns — Architecture patterns for modern API gateways
- MCP Gateway Concepts — Understanding AI-native gateway architecture
- Enterprise AI-Native Gateway Benchmark — Why proxy throughput is the wrong metric for AI gateways
Christophe Aboulicam is the Founder & CTO at HLFH. He has spent 15 years in API management and integration, most recently building STOA to address the AI-native future of enterprise APIs.
Disclaimer: Feature comparisons are based on publicly available documentation as of February 2026. Product capabilities change frequently. We encourage readers to verify current features directly with each vendor. All trademarks belong to their respective owners.