Documentation Index
Fetch the complete documentation index at: https://docs.burn0.dev/llms.txt
Use this file to discover all available pages before exploring further.
Configuration
burn0 is configured via environment variables. No config files needed for basic usage.
Environment variables
| Variable | Required | Default | Description |
|---|
BURN0_API_KEY | No | — | API key for cloud mode. Get one at burn0.dev. |
BURN0_API_URL | No | https://api.burn0.dev | Override the backend URL (for self-hosting or development). |
BURN0_DEBUG | No | false | Set to 1 to enable debug logging. |
BURN0_ENABLE_TEST | No | — | Set to 1 to enable tracking in NODE_ENV=test. |
Runtime modes
burn0 automatically detects the right mode based on your environment:
| Mode | When | Behavior |
|---|
| dev-local | TTY + no API key | Ticker in terminal, local ledger, no cloud sync |
| dev-cloud | TTY + API key | Ticker in terminal, local ledger, cloud sync |
| prod-cloud | No TTY + API key | Silent, cloud sync only |
| prod-local | No TTY + no API key | Logs warning, skips tracking entirely |
| test-disabled | NODE_ENV=test | No tracking (default in tests) |
| test-enabled | NODE_ENV=test + BURN0_ENABLE_TEST=1 | Full tracking in tests |
Local storage
burn0 stores data locally in the .burn0/ directory:
| File | Purpose |
|---|
.burn0/config.json | Project config (services, plans) |
.burn0/costs.jsonl | Event ledger (last 7 days) |
.burn0/pricing-cache.json | Cached pricing data (24h TTL) |
.burn0/ to your .gitignore — burn0 init does this automatically.
Disabling burn0
To temporarily disable burn0 without removing the import:
# In tests (default behavior)
NODE_ENV=test npm test
# In production without API key
# burn0 automatically skips patching and logs a warning
Restoring original behavior
To programmatically unpatch fetch and http:
import { restore } from '@burn0/burn0'
restore() // Removes all burn0 patches
