diff --git a/lib/src/error.rs b/lib/src/error.rs
index 336695ef..70cb1b10 100644
--- a/lib/src/error.rs
+++ b/lib/src/error.rs
@@ -2,6 +2,7 @@ use miette::{Diagnostic, NamedSource, SourceSpan};
 use thiserror::Error;
 
 #[derive(Error, Diagnostic, Debug)]
+#[non_exhaustive]
 pub enum UsageErr {
     #[error("Invalid flag `{token}`: {reason}")]
     InvalidFlag {
diff --git a/lib/src/parse.rs b/lib/src/parse.rs
index 2c0eb40c..51cb982b 100644
--- a/lib/src/parse.rs
+++ b/lib/src/parse.rs
@@ -238,6 +238,7 @@ fn get_flag_key(word: &str) -> &str {
     }
 }
 
+#[non_exhaustive]
 pub struct ParseOutput {
     pub cmd: SpecCommand,
     pub cmds: Vec<SpecCommand>,