✦ For Vercel · Next.js · Edge Functions · Middleware ✦
Vercel keeps dashboard logs for about one hour. FlareLog captures, structures, and stores your Next.js, Serverless, and Edge logs for days — with a minimal SDK install and zero config.
Logs Expired
Upgrade to Pro for longer retention
90d
retention on Pro
~3
lines to install
10k
free logs/mo
$19
flat Pro bucket
You shipped on Vercel. But at 2am your function errors and the logs are already gone.
Vercel's built-in logging is fine for quick checks. It's not built for incident response, cost debugging, or asking your AI why a production checkout failed. FlareLog is.
No OpenTelemetry acrobatics. No heavy runtime dependencies. Pick the wrapper that matches your Vercel stack.
Install the SDK
Run npm install @flarelog/sdk. One package covers Next.js, Vercel Serverless, Edge, and Middleware.
Set your API key
Add FLARELOG_API_KEY as a Vercel environment variable. The SDK auto-detects Vercel's runtime env vars.
Wrap your handler
Use withFlareLog for Next.js, or withVercelServerless / withVercelEdge for raw Vercel routes.
Connect MCP (optional)
Paste the MCP config into Cursor, Claude Desktop, or Lovable and ask your AI "why did /api/checkout fail?" using live production logs.
import { flarelog } from "@flarelog/sdk";
import { withFlareLog } from "@flarelog/sdk/next";
const logger = flarelog({ apiKey: process.env.FLARELOG_API_KEY });
export default withFlareLog(logger, async (req, res) => {
req.logger.info("Checkout started", { cartId: req.body.cartId });
const payment = await stripeCheckout(req.body);
req.logger.info("Payment complete", { paymentId: payment.id });
res.json({ ok: true });
});import { flarelog } from "@flarelog/sdk";
import { withVercelServerless } from "@flarelog/sdk/vercel";
const logger = flarelog({ apiKey: process.env.FLARELOG_API_KEY });
export default withVercelServerless(logger, async (req, res) => {
req.logger.info("API request", { path: req.url });
const result = await fetch("https://api.example.com/data");
req.logger.debug("Upstream response", { status: result.status });
res.json({ data: await result.json() });
});import { flarelog } from "@flarelog/sdk";
import { withVercelEdge } from "@flarelog/sdk/vercel";
export const config = { runtime: "edge" };
const logger = flarelog({ apiKey: process.env.FLARELOG_API_KEY });
export default withVercelEdge(logger, async (request) => {
logger.info("Edge request", { url: request.url });
const response = await fetch(request);
logger.info("Edge response", { status: response.status });
return response;
});# Add to your Vercel project
vercel env add FLARELOG_API_KEY
# or paste in the dashboard
FLARELOG_API_KEY=fl_your_api_keyStop losing context after one hour. FlareLog gives you 7 days free and 90 days on Pro so you can debug last week's incident without replaying traffic.
Filter by stripeEvent, Prisma query, App Router path, or any nested field. Vercel's text-only search can't do that.
Background work like webhooks and waitUntil often vanish when a serverless function freezes. FlareLog flushes them before the invocation ends.
Vercel meters observability events alongside requests. One bot swarm or Product Hunt launch can inflate both. FlareLog buckets your logs for a flat $19/mo up to 2M logs.
Why it matters
A scraper hitting every route can generate millions of log events. FlareLog's Pro bucket absorbs that instead of multiplying your bill.
Why it matters
Product Hunt traffic is a good problem — unless your logging bill scales linearly with it. Flat-rate monitoring keeps launches stress-free.
Why it matters
You can't stop every attack, but you can stop one from turning into a five-figure observability invoice. Your costs stay bounded.
FlareLog's MCP server connects Cursor, Claude Desktop, or Lovable Agent to your real Vercel logs. No browser tab, no manual grep, no copy-pasting stack traces.
{
"mcpServers": {
"flarelog": {
"url": "https://mcp.flarelog.dev",
"headers": {
"Authorization": "Bearer fl_your_api_key"
}
}
}
}↑ Paste into Cursor, Claude Desktop, or Lovable Connectors. Done.
No — it complements them. Vercel gives you traffic and Web Vitals. FlareLog gives you searchable structured logs, error grouping, cost burn alerts, and AI-native debugging.
The SDK adds sub-millisecond overhead. Logs are batched and flushed asynchronously, so request latency stays untouched.
Yes. Use withVercelEdge for Edge Functions and Middleware. It runs natively on the Edge runtime with zero dependencies.
Use withFlareLog from @flarelog/sdk/next. It works for API routes, route handlers, and server actions on any Node.js server including Vercel.
No. FlareLog is a separate observability service. You can stay on any Vercel tier and ship logs to FlareLog with one environment variable.
Yes. Start with 10,000 logs/mo and 7-day retention on the free tier. Upgrade to Pro when you need 2M logs/mo, 90-day retention, Slack alerts, and the cost burn dashboard.
Free tier includes 10,000 logs/month and all core features. No credit card. No marketplace integration needed — just install the SDK.