The fundamental challenge of open-source ETL is that high-quality connectors require understanding and working around all kinds of corner cases in the API of each data source. It’s very hard to get open source contributors to do this kind of work; it’s a real slog. Hence at Fivetran we’ve always stuck with the commercial route.
Our perspective is that by providing these connectors as open source we can arrive at higher quality connectors. For a closed source solution, a user has to go through customer service and persuade them that there is indeed a problem. A story we have heard countless times, is that SaaS ETL providers are slow to fix corner cases discovered by users leading to extended downtime. With an OSS solution, a user can fix a problem themselves and be back online immediately.
We proactively maintain all connectors, but we believe that by sharing that responsibility with the OSS community, we can achieve the highest quality connectors.
One of the main focuses of Airbyte is to provide a very strong open-source MIT standard for testing and developing (base packages, standard tests, best practices…) connectors in order to achieve the highest quality.