fastify vs hono

backend

fastify

hono

Fastify and Hono are both modern JavaScript backend frameworks, but they target fundamentally different deployment models. Fastify is a high-performance Node.js framework designed for traditional server environments, offering 22,000 req/s throughput with built-in schema validation, logging, and a mature plugin ecosystem. Hono is a lightweight, runtime-agnostic framework optimized for edge and serverless platforms like Cloudflare Workers, Deno Deploy, and Vercel Edge Functions, weighing in at roughly 5x smaller than Express with zero dependencies.

This comparison matters because choosing the wrong framework for your deployment target creates unnecessary overhead. Fastify developers typically build monolithic APIs or microservices running on dedicated Node.js servers where throughput and feature richness matter most. Hono developers prioritize cold start performance, multi-runtime compatibility, and minimal memory footprint for distributed edge computing or serverless architectures where every millisecond and megabyte counts.

Head-to-Head

Node.js Server Performance→ fastify wins

fastify

Delivers 22,000 req/s with 32ms p99 latency on Node.js, 2x faster JSON serialization than Express, and 40% lower CPU usage. Purpose-built for Node.js with native optimizations.

hono

Historically slower on Node.js due to Web Standard API conversion overhead, but February 2025 adapter improvements significantly narrowed the gap. Still not as optimized as Fastify for traditional Node.js servers.

Edge/Serverless Performance→ hono wins

fastify

Not designed for serverless environments. Heavier bundle size and architecture assumptions around long-running processes make it suboptimal for edge deployments with cold starts.

hono

Dominates with 120ms cold starts (vs 450ms for Express), 18MB memory usage (vs 120MB), and native compatibility with Cloudflare Workers, Deno Deploy, and Vercel Edge. Built specifically for this use case.

Runtime Compatibility→ hono wins

fastify

Node.js only. The plugin ecosystem, lifecycle hooks, and performance optimizations are tightly coupled to Node.js APIs and assumptions.

hono

Runs natively on Node.js, Deno, Bun, Cloudflare Workers, and other Web Standard-compliant runtimes. Achieves 136,112 req/s on Deno. Single codebase works across all platforms.

Built-in Features & Ecosystem→ fastify wins

fastify

Comprehensive plugin architecture with official plugins for authentication, rate limiting, CORS, compression, and more. Schema-based validation with JSON Schema and built-in logging/tracing. Mature ecosystem with battle-tested patterns.

hono

Minimal core with middleware for common tasks. No built-in schema validation or logging framework. Philosophy favors small size over batteries-included approach. Growing but significantly smaller ecosystem.

Bundle Size & Dependencies→ hono wins

fastify

Heavier footprint with dependencies that provide extensive features. Not optimized for bundle size since traditional servers don't face cold start penalties from larger packages.

hono

Zero dependencies and approximately 5x smaller than Express. Designed for environments where every KB affects cold start time and where tree-shaking and minimal overhead are critical.

API Design & Developer Experiencetie

fastify

Schema-driven development with automatic validation and serialization. Lifecycle hooks, decorators, and encapsulation through plugins. More boilerplate but greater structure for large teams and complex applications.

hono

Modern, minimalist API inspired by Express but cleaner. Chainable middleware, straightforward routing, and less ceremony. Easier to learn but provides less structure for large codebases without additional tooling.

Verdict

Choose Fastify if you're building traditional Node.js APIs that will run on dedicated servers, containers, or VM-based infrastructure. Its superior Node.js throughput (22,000 req/s vs lower for Hono on Node), comprehensive plugin ecosystem, and built-in schema validation make it ideal for high-load JSON APIs, complex microservices, or any scenario where you're optimizing for steady-state performance rather than cold starts. The mature ecosystem and structured approach also benefit larger teams maintaining complex applications.

Choose Hono if your deployment target is edge computing, serverless functions, or you need runtime flexibility. With 120ms cold starts versus 450ms, 18MB memory footprint versus 120MB, and native support for Cloudflare Workers, Deno, Bun, and Node.js, Hono is purpose-built for distributed, pay-per-request architectures. The minimal bundle size directly translates to cost savings on platforms that charge per invocation and penalize cold starts. A hybrid strategy—Fastify for your main API and Hono for edge caching layers—can deliver 3x throughput with 60% lower cloud costs.

When to Use Each

If you are building a REST API for a SaaS product running on AWS ECS or DigitalOcean → use Fastify because you need maximum throughput on Node.js servers and benefit from built-in validation, logging, and the mature plugin ecosystem for authentication and rate limiting.

If you are building API endpoints for a Next.js app deployed on Vercel Edge Functions → use Hono because the 18MB memory footprint and 120ms cold starts are critical for serverless economics and user-perceived latency on edge networks.

If you are building a GraphQL server running on a Kubernetes cluster → use Fastify because the long-running process model amortizes startup costs, and you need the schema validation and plugin architecture for complex resolver logic and middleware chains.

If you are building a multi-cloud application that must run on Node.js, Deno, and Cloudflare Workers → use Hono because it's the only framework providing true write-once-run-anywhere compatibility across these runtimes with consistent APIs and performance characteristics.

Learn More

fastify →hono →

Head-to-Head

Node.js Server Performance→ fastify wins

fastify

Delivers 22,000 req/s with 32ms p99 latency on Node.js, 2x faster JSON serialization than Express, and 40% lower CPU usage. Purpose-built for Node.js with native optimizations.

hono

Edge/Serverless Performance→ hono wins

fastify

Not designed for serverless environments. Heavier bundle size and architecture assumptions around long-running processes make it suboptimal for edge deployments with cold starts.

hono

Runtime Compatibility→ hono wins

fastify

Node.js only. The plugin ecosystem, lifecycle hooks, and performance optimizations are tightly coupled to Node.js APIs and assumptions.

hono

Runs natively on Node.js, Deno, Bun, Cloudflare Workers, and other Web Standard-compliant runtimes. Achieves 136,112 req/s on Deno. Single codebase works across all platforms.

Built-in Features & Ecosystem→ fastify wins

fastify

hono

Bundle Size & Dependencies→ hono wins

fastify

Heavier footprint with dependencies that provide extensive features. Not optimized for bundle size since traditional servers don't face cold start penalties from larger packages.

hono

Zero dependencies and approximately 5x smaller than Express. Designed for environments where every KB affects cold start time and where tree-shaking and minimal overhead are critical.

API Design & Developer Experiencetie

fastify

hono

Verdict

When to Use Each