Its not strange, its very common. Its called "bootstrapping".
> Bootstrapping is a fairly common practice when creating a programming language. Many compilers for many programming languages are bootstrapped, including compilers for ALGOL, BASIC, C, C#, Common Lisp, D, Eiffel, Elixir, Go, Haskell, Java, Modula-2, Nim, Oberon, OCaml, Pascal, PL/I, Python, Rust, Scala, Scheme, TypeScript, Vala, Zig and more.
[ my public key: https://keybase.io/styfle; my proof: https://keybase.io/styfle/sigs/k5Jx2P3fJ9JOZsHyU2TLChLetDsvmL2mHK7wJMj-nKk ]