Meltano

Meltano is an open-source, code-first DataOps platform for building and managing ELT pipelines. Created inside GitLab in 2018 and later spun out, it lets data engineers assemble extract-load-transform pipelines from a catalog of 600-plus Singer-based connectors, treating data integration as version-controlled code rather than clicks in a proprietary UI.

The platform embraces software-engineering practices for data: pipelines are defined in configuration and code, tracked in Git, tested, and deployed through CI/CD, with dbt for transformations. This code-first, modular approach appeals to engineering teams that want full control, transparency, and the ability to run pipelines anywhere without vendor lock-in, unlike closed managed connectors.

Meltano is available as a free, self-managed open-source project under the MIT license, alongside a paid Pro tier from around 25 dollars per month for team workflows and a custom Enterprise tier, plus managed hosting options. Now stewarded by Matatika, it competes with Airbyte, Fivetran, and Stitch as the choice for teams that prize open source, code-first control, and the huge Singer connector ecosystem over fully managed convenience.