head to head · open source
Grafana Loki vs semantic_logger
Grafana Loki has 28,917 GitHub stars, 4,115 forks, 1,620 open issues and last shipped yesterday. semantic_logger has 956 stars, 139 forks, 0 open issues and last shipped 14 days ago. Grafana Loki leads on adoption by 2,925% (28,917 vs 956 stars). Grafana Loki is written in Go under AGPL-3.0; semantic_logger is written in Ruby under Apache-2.0. Grafana Loki has attracted 14% as many forks as stars, semantic_logger 15%. Grafana Loki 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
| Grafana Loki | semantic_logger | |
|---|---|---|
| GitHub stars | ★ 29K | ★ 956 |
| License | AGPL-3.0 | Apache-2.0 |
| Written in | Go | Ruby |
| Last push | 2026-09-19 | 2026-09-06 |
| Forks | ⑂ 4.1K | ⑂ 139 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Grafana Loki if
- You weight community size — 29K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Go
- 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 Grafana Loki
Grafana Loki is a log aggregation system designed as the log oriented counterpart to Prometheus. It operates within the cloud native observability ecosystem, specifically targeting Kubernetes and containerized environments. Loki avoids expensive full text indexing by indexing only metadata labels attached to log streams, storing the raw log content in compressed form. This design choice makes Loki significantly simpler to operate and more cost effective than traditional log systems that index every word.
read the full Grafana Loki 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 Grafana Loki or semantic_logger more popular?
Grafana Loki has 28,917 GitHub stars and semantic_logger has 956. Grafana Loki has the larger community by that measure.
Are Grafana Loki and semantic_logger free?
Both are open source. Grafana Loki is licensed under AGPL-3.0 and semantic_logger under Apache-2.0. Neither carries a licence fee.
What is the difference between Grafana Loki and semantic_logger?
Grafana Loki is written in Go 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, Grafana Loki or semantic_logger?
Choose Grafana Loki if you want the larger community (28,917 stars) or its AGPL-3.0 licence terms. Choose semantic_logger if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.