The list is of 8 tools. What is this 9th one? If you feel after reading the top 8 that your answer is NOTA (None of the above), you could explore building a DIY Internal Developer Portal.
In case of doing so, here are some of the top reasons why other companies are doing that:
1. If you feel that your team is opinionated to not using Backstage due to it’s dependency on Javascript
2. If you have too many internally built tools for CI / CD and usual developer workflows and not too many options in Backstage plugins
3. If your team’s size can justify dedicating a few full-time resources to building it internally.
While building an internal developer portal in-house for scaffolding and developer self-service might be a suitable option, it is worth re-evaluating the cloud tools available given the extensive integrations with other commercial SaaS offerings that they have in the market.