diff --git a/CHANGELOG.md b/CHANGELOG.md
index eec96428..316263c6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.9.1] - 2022-01-11
+
+### Changed
+- The generated Rust code is now slightly more DRY.
+
 ## [0.9.0] - 2022-01-11
 
 ### Changed
diff --git a/Cargo.lock b/Cargo.lock
index ea8c3871..1f8e1673 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -162,7 +162,7 @@ dependencies = [
 
 [[package]]
 name = "typical"
-version = "0.9.0"
+version = "0.9.1"
 dependencies = [
  "clap",
  "colored",
diff --git a/Cargo.toml b/Cargo.toml
index 29826cdc..481d09ec 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "typical"
-version = "0.9.0"
+version = "0.9.1"
 authors = ["Stephan Boyer <stephan@stephanboyer.com>"]
 edition = "2021"
 description = "Algebraic data types for data interchange."
diff --git a/src/generate_rust.rs b/src/generate_rust.rs
index 58948375..5ebc5a30 100644
--- a/src/generate_rust.rs
+++ b/src/generate_rust.rs
@@ -95,6 +95,8 @@ use std::{{
     mem::transmute,
 }};
 
+const MISSING_FIELDS_ERROR_MESSAGE: &str = \"Struct missing one or more required field(s).\";
+
 pub trait Serialize {{
     fn size(&self) -> usize;
 
@@ -638,7 +640,8 @@ fn write_schema<T: Write>(
                     write_indentation(buffer, indentation + 4)?;
                     writeln!(buffer, "::std::io::ErrorKind::InvalidData,")?;
                     write_indentation(buffer, indentation + 4)?;
-                    writeln!(buffer, "\"Struct missing one or more field(s).\",")?;
+                    write_supers(buffer, indentation)?;
+                    writeln!(buffer, "MISSING_FIELDS_ERROR_MESSAGE,")?;
                     write_indentation(buffer, indentation + 3)?;
                     writeln!(buffer, "));")?;
                     write_indentation(buffer, indentation + 2)?;
diff --git a/test_data/types.rs b/test_data/types.rs
index 4f5caa4f..77b2df07 100644
--- a/test_data/types.rs
+++ b/test_data/types.rs
@@ -7,6 +7,8 @@ use std::{
     mem::transmute,
 };
 
+const MISSING_FIELDS_ERROR_MESSAGE: &str = "Struct missing one or more required field(s).";
+
 pub trait Serialize {
     fn size(&self) -> usize;
 
@@ -306,7 +308,7 @@ pub mod circular_dependency {
                     if _x.is_none() {
                         return Err(::std::io::Error::new(
                             ::std::io::ErrorKind::InvalidData,
-                            "Struct missing one or more field(s).",
+                            super::super::super::MISSING_FIELDS_ERROR_MESSAGE,
                         ));
                     }
 
@@ -470,7 +472,7 @@ pub mod circular_dependency {
                     || _fallback.is_none() {
                     return Err(::std::io::Error::new(
                         ::std::io::ErrorKind::InvalidData,
-                        "Struct missing one or more field(s).",
+                        super::super::MISSING_FIELDS_ERROR_MESSAGE,
                     ));
                 }
 
@@ -2755,7 +2757,7 @@ pub mod comprehensive {
                     || _aa_required.is_none() {
                     return Err(::std::io::Error::new(
                         ::std::io::ErrorKind::InvalidData,
-                        "Struct missing one or more field(s).",
+                        super::super::MISSING_FIELDS_ERROR_MESSAGE,
                     ));
                 }
 
@@ -7902,7 +7904,7 @@ pub mod schema_evolution {
                     || _optional_to_required.is_none() {
                     return Err(::std::io::Error::new(
                         ::std::io::ErrorKind::InvalidData,
-                        "Struct missing one or more field(s).",
+                        super::super::MISSING_FIELDS_ERROR_MESSAGE,
                     ));
                 }
 
@@ -8620,7 +8622,7 @@ pub mod schema_evolution {
                     || _required_to_nonexistent.is_none() {
                     return Err(::std::io::Error::new(
                         ::std::io::ErrorKind::InvalidData,
-                        "Struct missing one or more field(s).",
+                        super::super::MISSING_FIELDS_ERROR_MESSAGE,
                     ));
                 }
 
@@ -9197,7 +9199,7 @@ pub mod schema_evolution {
                 if _x.is_none() {
                     return Err(::std::io::Error::new(
                         ::std::io::ErrorKind::InvalidData,
-                        "Struct missing one or more field(s).",
+                        super::super::MISSING_FIELDS_ERROR_MESSAGE,
                     ));
                 }