head to head · open source
monolog vs semantic_logger
monolog has 21,405 GitHub stars, 1,910 forks, 3 open issues and last shipped yesterday. semantic_logger has 956 stars, 139 forks, 0 open issues and last shipped 14 days ago. monolog leads on adoption by 2,139% (21,405 vs 956 stars). monolog is written in PHP under MIT; semantic_logger is written in Ruby under Apache-2.0. monolog has attracted 9% as many forks as stars, semantic_logger 15%. monolog was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (logging), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| monolog | semantic_logger | |
|---|---|---|
| GitHub stars | ★ 21K | ★ 956 |
| License | MIT | Apache-2.0 |
| Written in | PHP | Ruby |
| Last push | 2026-09-19 | 2026-09-06 |
| Forks | ⑂ 1.9K | ⑂ 139 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick monolog if
- You weight community size — 21K stars and counting
- You want the MIT license terms
- Your stack matches PHP
- You value the larger contributor base for long-term maintenance
pick semantic_logger if
- You want the semantic_logger feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Ruby
- You evaluated both and semantic_logger fits your workflow better
About monolog
Monolog is a logging library for PHP that sends log records to files, sockets, inboxes, databases, and various web services. It ships with the handlers, formatters, and processors needed to route records where they belong, and special handlers allow more advanced logging strategies than a single output stream. The library lives in the PHP ecosystem and is distributed through Packagist as monolog/monolog . It is released under the MIT license and has been developed for sixteen years, with more than twenty one thousand stars and roughly nineteen hundred forks on GitHub.
read the full monolog overview →
About semantic_logger
Semantic Logger is a high performance, asynchronous structured logging framework for Ruby and Rails that pushes log events onto an in memory queue and writes them to one or more destinations from a separate background thread.
read the full semantic_logger overview →
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Frequently asked questions
Is monolog or semantic_logger more popular?
monolog has 21,405 GitHub stars and semantic_logger has 956. monolog has the larger community by that measure.
Are monolog and semantic_logger free?
Both are open source. monolog is licensed under MIT and semantic_logger under Apache-2.0. Neither carries a licence fee.
What is the difference between monolog and semantic_logger?
monolog is written in PHP and semantic_logger in Ruby. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, monolog or semantic_logger?
Choose monolog if you want the larger community (21,405 stars) or its MIT licence terms. Choose semantic_logger if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.