Custom MSSQL datasource : Could not find executor

I am using the https://github.com/grafana/simple-datasource/tree/master simple data source plugine template, and I am able to build it, and see it in grafana. I modified the fields to configure the datasource with a host, database name, user and password, and I am able to configure them in the same way as the builtin mssql plugin.

When I “save & test” the datasource I get the “Metricrequest error”. In the logfiles I see that there is an error that the “executor” does not know the datasource type. The type mentioned is the ID of my plugin. I compared the package.json to the builtin mssql datasource and there the ID is mssql.

t=2020-07-09T09:13:12+0000 lvl=eror msg="Metric request error" logger=context userId=1 orgId=1 uname=admin error="Could not find executor for data source type: my-custom-datasource" remote_addr=[::1]

I suspect that the ID is used to have grafana select the correct server, in my case it should be a mssql server. How can I make clear that my plugin should use the MSSQL executor from grafana ?

Reason that I create a custom datasource is because we have a very specific need for a query builder that is able to let the user select only a “IO name” and no other option to “mess” with queries

grafana : v7.0.3 (00ee734baf) on WIndows 10

Can I do something with datasource.DatasourcePluginImpl{Plugin: ... mssql plugin ... from within my custom datasource plugin ?