Half your dependencies
won't even run here.
Edge Runtime doesn't support Node.js APIs. That means no crypto, no fs,
and half the packages on npm just crash at runtime. TinyFn works everywhere—it's just fetch().
Edge Runtime Compatibility
Complete Example
A production-ready Next.js middleware with zero dependencies.
Edge Runtime is not Node.js
Vercel's Edge Runtime uses V8 isolates, not Node.js. That means no Buffer, no crypto,
no fs, and no native modules. Packages like bcrypt, jsonwebtoken, and
uuid (v4) won't work. TinyFn sidesteps all of this—it's just HTTP.
import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';
const TINYFN = 'https://api.tinyfn.io/v1';
export const config = { matcher: '/api/:path*' };
export async function middleware(request: NextRequest) {
const apiKey = process.env.TINYFN_API_KEY!;
const clientIP = request.ip || request.headers.get('x-forwarded-for') || '';
// Check if IP is in blocked range
const { in_range } = await fetch(
`${TINYFN}/ip/in-cidr?ip=${clientIP}&cidr=10.0.0.0/8`,
{ headers: { 'X-API-Key': apiKey } }
).then(r => r.json());
if (in_range) {
return new NextResponse('Forbidden', { status: 403 });
}
// Generate request ID for tracing
const { uuid } = await fetch(`${TINYFN}/generate/uuid`, {
headers: { 'X-API-Key': apiKey }
}).then(r => r.json());
const response = NextResponse.next();
response.headers.set('x-request-id', uuid);
return response;
}Quick Start
Add TinyFn to your Next.js project in under a minute.
Get API Key
# Sign up at tinyfn.io
# Copy your API keyAdd to Environment
# .env.local
TINYFN_API_KEY=your_keyUse in Middleware
await fetch(`${TINYFN}/...`,
{ headers: { 'X-API-Key': key } }
)Patterns That Just Work
Things you'd normally need a package for—now they're one fetch() away. No import errors, no bundle bloat.
A/B Test Assignment
// Consistent user bucketing
const { hash } = await fetch(
`${TINYFN}/hash/sha256?text=${userId}-exp`,
{ headers: { 'X-API-Key': key } }
).then(r => r.json());
const bucket = parseInt(hash.slice(0, 8), 16) % 100;
const variant = bucket < 50 ? 'A' : 'B';JWT Auth Check
// Decode JWT without a library
const token = request.headers.get('authorization')
?.replace('Bearer ', '');
const { payload } = await fetch(
`${TINYFN}/jwt/decode?token=${token}`,
{ headers: { 'X-API-Key': key } }
).then(r => r.json());
if (payload.role !== 'admin') { ... }Webhook Verification
// Verify Stripe/GitHub webhooks
const { hash } = await fetch(
`${TINYFN}/crypto/hmac-sha256?` +
`text=${encodeURIComponent(body)}&` +
`key=${WEBHOOK_SECRET}`,
{ headers: { 'X-API-Key': key } }
).then(r => r.json());
const valid = hash === signature;Form Validation
// Validate email at the edge
const { is_valid, disposable } = await fetch(
`${TINYFN}/validate/email?email=${email}`,
{ headers: { 'X-API-Key': key } }
).then(r => r.json());
if (!is_valid || disposable) {
return Response.json({ error: 'Invalid' });
}Popular Endpoints
Most-used utilities for Edge Functions.
Why This Works
The Edge Runtime is powerful but picky. TinyFn fits perfectly.
It Just Works
No more "Dynamic Code Evaluation" errors. No "Module not found". Just fetch().
No Bundle Anxiety
Stop worrying about the 4 MB limit. TinyFn adds literally zero bytes.
Ship Faster
No time spent finding "Edge-compatible" alternatives. It's all here.
Sleep Better
One API to keep updated vs a dozen packages with CVE alerts.
Stop fighting the Edge Runtime
Free tier gets you 10,000 requests/month. Enough to try it in your next middleware.