Helicone
Apache-2.0 LLM observability proxy, now reported to be in maintenance mode.
Helicone is an Apache-2.0 LLM observability platform known for one-line integration by changing the API base URL; its backend runs on Cloudflare Workers with ClickHouse and Kafka and the vendor reported over 2 billion handled calls, but multiple sources report it entered maintenance mode after an acquisition by Mintlify in March 2026.
Caveat: Reported to be in maintenance mode following a March 2026 acquisition; verify current activity before adopting for new production use.
Key facts
| Category | Observability |
|---|---|
| License | Apache-2.0 |
| Language | TypeScript |
| Self-hosted | Yes |
| GitHub stars | 6,199 (2026-10-04) |
| Last push | 2026-09-16 |
| Last verified | 2026-10-04 |
| Repository | https://github.com/Helicone/helicone |
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