Changelog

All notable changes to Logpilot are documented here. This project follows Semantic Versioning and Keep a Changelog.

[2.1.0] – 2026-03-01

Added

• HTTP transport – batch log entries and POST them to any HTTP endpoint (#88)
• transportError event – emitted when a transport's write method throws, so failures never crash the host application (#91)
• TypeScript: exported Transport and Formatter interfaces for custom implementations

Changed

• FileTransport now creates parent directories automatically if they don't exist

Fixed

• Fixed prettyFormatter dropping metadata fields that contained null values (#94)

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[2.0.0] – 2026-01-15

Breaking changes

Migrating from v1?

Version 2.0 includes breaking changes. See the migration guide below.

• Removed: log.log() method – use the specific level methods (log.info(), log.error(), etc.) instead
• Changed: The format config option is now called formatter and accepts a function, not a string
• Changed: FileTransport option path renamed to filename for clarity

Added

• fatal log level (severity 50) – higher than error, intended for unrecoverable failures
• prettyFormatter for colourised development output
• log.child(metadata) – create a child logger with pre-attached context fields

Improved

• Timestamp precision increased from seconds to milliseconds
• 40% reduction in memory allocation per log entry (benchmark: #72)

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[1.3.2] – 2025-11-20

Fixed

• StdoutTransport wasn't flushing the buffer before process exit on Windows (#61)
• Circular references in metadata no longer throw – they're replaced with [Circular]

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[1.3.0] – 2025-09-05

Added

• FileTransport with daily log rotation and configurable retention period
• log.setLevel(level) – change the minimum log level at runtime

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[1.0.0] – 2025-06-01

Initial stable release.

• Logger class with debug, info, warn, and error levels
• jsonFormatter – structured JSON output
• StdoutTransport – write to stdout
• Full TypeScript definitions

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Migrating from v1

Update the formatter config

// v1
const log = new Logger({ format: 'json' });

// v2
const { jsonFormatter } = require('logpilot/formatters');
const log = new Logger({ formatter: jsonFormatter });

Replace log.log() calls

// v1
log.log('info', 'Server started');

// v2
log.info('Server started');

Update FileTransport option name

// v1
new FileTransport({ path: './logs/app.log' });

// v2
new FileTransport({ filename: './logs/app.log' });