Model versioning and migrations

[cdietrich]

Hi, we are looking into having a more stable DSL as API. This means we do want to keep the syntax of the DSLs stable and if we break to either avoid it or to offer automatic migrations, also mid/long term. Did someone already make some experience in such a usecase. One question would also be how to implement and keep/maintain the migrations

• separate tool / codebase / branch
  • regex based
  • keep a lightweight chevrotain and or langium grammar
    • do it on ast, cst, a combination
• keep the grammar backwards compatible (might be very challenging also metamodel wise)
• keep a 2nd grammar in the current code base
  • might be very challenging AST namespacing wise

any other ideas?