Logrus
Structured, pluggable logging for Go. Logrus was the most popular Go logger before zerolog and zap emerged. Provides structured field logging, log hooks (execute code on log events), multiple formatters (JSON, text), log levels, and an API compatible with Go's standard log package. Note: Logrus is in maintenance mode — authors recommend migrating to zap or zerolog for new projects.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
MIT licensed. Maintenance mode — security patches still applied for critical issues. Avoid logging sensitive data in fields.
⚡ Reliability
Best When
You're maintaining an existing Go codebase that uses Logrus and migration to zap/zerolog isn't prioritized.
Avoid When
Starting a new Go project — use zap (typed fields) or zerolog (zero-allocation) instead. Logrus is in maintenance mode.
Use Cases
- • Maintain logging in existing Go agent services that already use Logrus without migration overhead
- • Add structured log hooks to existing agent services — route specific log levels to different outputs
- • Log to multiple destinations via Logrus hooks (file, syslog, external services) in legacy agent services
- • Implement entry-level field binding for request-scoped logging in existing Go agent codebases
- • Add structured fields to existing agent services using WithFields without full migration
Not For
- • New Go projects — logrus is maintenance-only; use zap or zerolog for new services
- • High-performance services — logrus uses reflection and allocates more than zap/zerolog
- • Services requiring zero-allocation logging — logrus cannot achieve zero-allocation
Interface
Authentication
Local library — no authentication required. MIT licensed.
Pricing
MIT licensed. Zero cost.
Agent Metadata
Known Gotchas
- ⚠ Logrus is in maintenance mode — production new services should use zap or zerolog; only maintain for existing codebases
- ⚠ logrus.WithField vs logrus.WithFields: WithField for single field, WithFields(logrus.Fields{'key': val}) for multiple — both return *Entry, not modify global logger
- ⚠ logrus.Entry.WithError(err) is shorthand for WithField('error', err) — idiomatic error logging
- ⚠ Hooks: logrus hooks execute synchronously in the logging goroutine — avoid slow hooks (network calls, disk writes) as they block logging
- ⚠ Thread safety: logrus.Logger is thread-safe; logrus.Entry is NOT — create new entries with logger.WithField() rather than modifying entries
- ⚠ JSON formatter: logrus.SetFormatter(&logrus.JSONFormatter{}) for structured JSON output in production; TextFormatter with colors for development
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Logrus.
Scores are editorial opinions as of 2026-03-06.