Overview

Architecture

See Architecture for a diagram of how a log travels from your app to your dashboard and alerts.

Core Concepts

Log Structure

Every log entry has a consistent structure across all SDKs:

{
  "type": "info",
  "message": "User logged in",
  "importance": "medium",
  "timestamp": 1705312800000,
  "subsystem": "auth",
  "operation": "login",
  "track": { "user_id": "user-123", "ip": "1.2.3.4" },
  "metrics": { "latency_ms": 45, "db_query_count": 1 },
  "security": { "auth_status": "success", "tags": ["login"] }
}

Field names are snake_case across every SDK.

Log Types

The available types depend on which SDK you use, because the method names differ:

Type	Next.js	Express	NestJS
`info`	`info()`	`info()`	`info()`
Non-fatal issue	`warning()`	`warn()`	`warn()`
`error`	`error()`	`error()`	`error()`
`audit`	`audit()`	`audit()`	`audit()`
`debug`	`debug()`	`debug()`	`debug()`
`metric`	`metric()`	`metric()`	`metric()`
`success`	`success()`	—	—

Each SDK exposes the method name that matches its own conventions.

Importance Levels

Set how urgent a log is. SnapLog orders these for you — you never set a numeric value.

Level	Use Case
`critical`	System down, data loss, security breach
`high`	Errors affecting users, failed payments
`medium`	Normal operations, audit events
`low`	Debug, metrics, success events

SDKs

Pick the SDK for your framework. Each one has its own page covering setup, every logging method, configuration, and webhook verification.

Next.js

@snaplog/next

Express

@snaplog/express

NestJS

@snaplog/nest

Key Features

Feature	What you get
Structured logs	Every log carries the same fields, so you can filter and search across all your apps
Automatic batching	Logs are bundled and sent every 2 seconds, so logging never slows down your app
Search and filter	Narrow results by type, environment, app, or free-text search
Live tail	Watch logs appear in the dashboard the moment they arrive
Alerts	Set a threshold over a time window, and get notified when it’s crossed
Notifications	Send alerts to Slack, Discord, email, or any webhook you own
No lost logs on shutdown	Pending logs are flushed when your app stops

Getting Started

SDKs

Architecture

Core Concepts

Log Structure

Log Types

Importance Levels

SDKs

Next.js

Express

NestJS

Key Features

Next steps

Architecture

Quickstart

​Architecture

​Core Concepts

​Log Structure

​Log Types

​Importance Levels

​SDKs

Next.js

Express

NestJS

​Key Features

​Next steps

Architecture

Quickstart

Architecture

Core Concepts

Log Structure

Log Types

Importance Levels

SDKs

Key Features

Next steps