Comment by jFriedensreich

I looked into four interesting incarnations of this over the years:

1. During the peak phase of couchDB as application server (2006 - 2009) it was common to store not just the data but all the app assets and code in the database and replicate everything together. Plenty of the community tried to bring this to the extreme with every function being stored as versioned document (i see it as precursor to FAAS) and the whole application being editable with an integrated IDE. Also functions in my incarnation of this system were not loaded by filename but with a content addressed manifest. You would reference functions by name but the name would be resolved with a hash manifest.

2. There were several systems with erlang/BEAM to take the hot code replacement to the extreme in similar way, storing code in i believe mnesia.

3. I think bloomberg (i cannot find the hn post to confirm it was them, if someone has the link that would be great) has/had a bespoke code database with custom version control and fully integrated IDE. They leveraged this for some pretty interesting workflows

4. Probably not exactly what you mean as it does not include the runtime integration, but google and sourcegraph are building code databases with indices on symbols and semantic understanding of references and more. I hear great things from people who worked with it especially