Fluent Bit

Judgement

What it is

Complete system

What it does

A small, fast agent in C that collects, processes and forwards logs, metrics and traces, widely used on Kubernetes nodes and embedded devices.

Adopt it when

You need a light log and metrics shipper on many machines or containers.

Watch out

Complex transformations are harder than in Vector or Fluentd, and config has two formats.

Ready for

Production-ready

Runs as

Self-hosted server

Built with

C

How established

Established: started 11 years ago, latest release v5.1.5.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Fluent Bit → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

Open-source alternatives to Fluent Bit

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Commercial telemetry collectors and pipelines

1. 1
   Datadog Observability Pipelines Datadog, Inc.

   Control costs, simplify SIEM migrations, and manage sensitive data at scale

   Complete system Production-ready You already pay for Datadog and want to control log volume or move data between SIEMs without adding another vendor.

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2. 2
   Cribl Stream Cribl

   Collect, reduce, and shape your data with Cribl Stream. Our product offers a simple way to drive your data engine forward. Start streaming today.

   Complete system Production-ready Your log ingest bill is large and you want to cut, reshape or split data before it reaches expensive analytics tools.

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