segi
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// An operator-grade ops console

Catch every error. Replay anything.

segi is a lightweight observability platform for Next.js, NestJS, and browser JavaScript apps. Group repeated errors into a single issue, replay what the user actually saw, watch URLs and PM2 processes, and alert your team the moment something new breaks.

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● 100 MB ingest / month free● no card to sign up● Seoul region
~/api-server · pnpm dev● live
$ pnpm add @segi/nextjs
+ @segi/nextjs 2.4.1 (3.1 MB)
$ echo SEGI_DSN=$SEGI_DSN
SEGI_DSN=segi://pub_a3f9c…@ingest.segi.io/3
$ pnpm dev
▲ ready in 1.2s · http://localhost:3000
[segi] first event captured ✓
[segi] ingest acked · 12 ms · seoul-1
$
// In one console

Five things ops teams use every day

Errors, health, processes, and alerts in one place — no separate tools to keep open.

01
Turn repeated errors into one issue
Stack-aware fingerprints group similar events automatically, so your team can focus on the root cause instead of scanning duplicate noise.
02
Replay what the user actually saw
rrweb-based DOM replay plays back clicks, inputs, and scrolls in pixel-perfect fidelity. Click heatmaps overlay on the real page so you immediately see where users get stuck.
03
Know when services drift
Probe any URL on a schedule and verify the response body. DOWN, TEXT_MISMATCH, and ERROR states make failures easy to classify.
04
See PM2 processes clearly
When hosts send `pm2 jlist` data, segi shows process status, CPU, memory, and restart counts in one live console.
05
Alerts your team won't miss
When a brand-new issue is first detected, verified members of the org get an email. Notifications are per-project, so you can keep late-night noise off the team.
// Session replay

Session replay & click heatmaps

When something breaks, see exactly what the user saw. Heatmaps from every session on the same page overlay on the real layout, so you spot the dead button on the first look.

What you'll see
  • Replay what the user actually saw, exactly as their page rendered — text stays selectable and you can see which inputs they touched, not just a flat video.
  • Heatmaps overlay click distribution on the real page, so it's immediately obvious where visitors got stuck or which buttons never got pressed.
  • Sessions auto-terminate and pause when the user steps away — background tabs never accumulate cost.
  • Passwords, emails, phone numbers and numeric inputs are auto-masked; sensitive areas can be hidden with a single class name.
// Issue feed

A live issue feed

What the admin console looks like — counts tick up as new events arrive.

Live
FATAL
TypeError: Cannot read properties of undefined (reading 'id')
checkout-api · /api/checkout
142
events
ERROR
fetch failed: timeout after 10000ms
web-shop · billing.ts:212
84
events
ERROR
Unhandled promise rejection: 401 Unauthorized
admin-web · /projects/12
63
events
WARNING
Database connection pool exhausted (50/50)
events-worker · prisma
32
events
ERROR
ZodError: Required at "body.userId"
checkout-api · /api/refund
19
events
INFO
RangeError: Invalid array length
web-shop · cart.tsx:47
8
events
// Alert email

New-issue alert email

When a brand-new issue is first detected, segi emails verified org members. This is what they see.

Sample alert email
segiextn · checkout-api
● New issue · FATAL

TypeError: Cannot read properties of undefined (reading 'id')

First seen 2 minutes ago in checkout-api · production · release v2.14.3. Already affecting 38 users across 142 events.

URL/api/checkoutUSERjihye@extn.aiRUNTIMEnode 20.11.0REGIONap-northeast-2
42  const userId = req.user.id;
43  await charge(userId, total);
44  return res.json({ ok: true });
Open issue in segi →
You're getting this because new-issue alerts are enabled for checkout-api.
// SDK

SDKs you can add quickly

Use the browser, Next.js, NestJS, or CDN bundle for plain HTML.

index.html
<script>
  window.SegiConfig = {
    projectKey: "segi_pk_live_xxxxx"
  };
</script>
<script src="https://cdn.extn.ai/segi/segi.min.js" async></script>

Your project key is generated when you create a project in the console. How to create a project →

When you're ready — grab a key.

No card required · 100 MB free per month.

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