diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9c2a4fe50..f58df9bc0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,6 +32,7 @@ set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+set(CMAKE_COMPILE_WARNING_AS_ERROR ON)
 
 option(ICEBERG_BUILD_STATIC "Build static library" ON)
 option(ICEBERG_BUILD_SHARED "Build shared library" OFF)
diff --git a/src/iceberg/file_format.h b/src/iceberg/file_format.h
index eebb76d14..8e7396a0b 100644
--- a/src/iceberg/file_format.h
+++ b/src/iceberg/file_format.h
@@ -26,6 +26,7 @@
 
 #include "iceberg/iceberg_export.h"
 #include "iceberg/result.h"
+#include "iceberg/util/unreachable.h"
 
 namespace iceberg {
 
@@ -49,6 +50,8 @@ ICEBERG_EXPORT inline std::string_view ToString(FileFormatType format_type) {
     case FileFormatType::kPuffin:
       return "puffin";
   }
+  internal::Unreachable(
+      std::format("Invalid file format type: {}", static_cast<int>(format_type)));
 }
 
 /// \brief Convert a string to a FileFormatType
diff --git a/src/iceberg/manifest_list.h b/src/iceberg/manifest_list.h
index ddcc38f73..432397ec1 100644
--- a/src/iceberg/manifest_list.h
+++ b/src/iceberg/manifest_list.h
@@ -30,6 +30,7 @@
 #include "iceberg/result.h"
 #include "iceberg/schema_field.h"
 #include "iceberg/type.h"
+#include "iceberg/util/unreachable.h"
 
 namespace iceberg {
 
@@ -221,6 +222,8 @@ ICEBERG_EXPORT constexpr std::string_view ToString(ManifestFile::Content type) n
     case ManifestFile::Content::kDeletes:
       return "deletes";
   }
+  internal::Unreachable(
+      std::format("Unknown manifest content type: {}", static_cast<int>(type)));
 }
 
 /// \brief Get the relative manifest content type from name
diff --git a/src/iceberg/snapshot.h b/src/iceberg/snapshot.h
index a16522a88..c52feefbc 100644
--- a/src/iceberg/snapshot.h
+++ b/src/iceberg/snapshot.h
@@ -28,6 +28,7 @@
 #include "iceberg/iceberg_export.h"
 #include "iceberg/result.h"
 #include "iceberg/util/timepoint.h"
+#include "iceberg/util/unreachable.h"
 
 namespace iceberg {
 
@@ -50,6 +51,8 @@ ICEBERG_EXPORT constexpr std::string_view SnapshotRefTypeToString(
     case SnapshotRefType::kTag:
       return "tag";
   }
+  internal::Unreachable(
+      std::format("Invalid snapshot reference type: {}", static_cast<int>(type)));
 }
 /// \brief Get the relative snapshot reference type from name
 ICEBERG_EXPORT constexpr Result<SnapshotRefType> SnapshotRefTypeFromString(