> Pkl — pronounced Pickle — is an embeddable configuration language which provides rich support for data templating and validation. It can be used from the command line, integrated in a build pipeline, or embedded in a program. Pkl scales from small to large, simple to complex, ad-hoc to repetitive configuration tasks.

I do like the sound of that. It's always quite tedious to manage configuration in full-stack applications with mixed languages/ecosystems. It seems they already have Pkl plugins for IntelliJ, vscode and neovim and a language server is "coming soon".