Let me clarify the reason for this. Many people asked for yaml support in composer, and it was shot down. Here's why: Once you start supporting many formats yo

Let me clarify the reason for this. Many people asked for yaml support in composer, and it was shot down. Here's why: Once you start supporting many formats you lose interoperability, as any tooling now needs to support all formats. That is the main reason why composer will not support sexpr.