title: Using Rust nightly in production
body: <p><strong>Can someone explain to me how "production" Rust nightly is?</strong></p>
  
  <p>I want to use the <a href="https://github.com/PyO3/pyo3/issues/5" rel="noreferrer">PyO3</a> crate which uses the <a href="https://github.com/rust-lang/rust/issues/31844" rel="noreferrer">specialization</a> feature that needs nightly Rust.</p>
  
  <p>Does using a nightly version of Rust is production ready? I understand that things might break in future releases and API changes might be introduced but in terms of quality/testing/production readiness is nightly safe?</p>
  
  <p>From <a href="https://users.rust-lang.org/t/how-stable-is-nightly/6326" rel="noreferrer">this thread on Rust users</a> it seems I should be fine as long as I limit my non-stable features usage (e.g. only to specialization)?</p>