Logstash vs Meltano

Logstash is an open-source, server-side pipeline that collects data from many sources, transforms events, and sends results to destinations. It can continuously ingest logs, metrics, web application data, data-store information, and AWS service data. Filters parse events, identify fields, and transform content with features such as grok parsing, IP geolocation, and anonymizing or excluding sensitive fields. Data can go to multiple outputs, including Elasticsearch. Its plugin framework includes more than 200 input, filter, and output plugins, and custom plugins can be built with an API and generator. Persistent queues provide at-least-once delivery for in-flight events after node failures; dead letter queues retain events for inspection and replay. Monitoring tools show pipeline performance and availability. Logstash supports log pipelines, archive export, live tailing, and structured parsing. It is self-hosted, with Linux packages and Docker listed. The free plan is free under the Elastic License.

Meltano has no write-up on Specifiction yet; its figures are above.