diff --git a/Cargo.lock b/Cargo.lock
index 323df3f..8ae7457 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -77,8 +77,16 @@ version = "0.1.0"
 dependencies = [
  "askama",
  "derive_more",
+ "strum",
+ "strum_macros",
 ]
 
+[[package]]
+name = "heck"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
+
 [[package]]
 name = "humansize"
 version = "2.1.3"
@@ -174,6 +182,12 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ffc183a10b4478d04cbbbfc96d0873219d962dd5accaff2ffbd4ceb7df837f4"
+
 [[package]]
 name = "semver"
 version = "1.0.18"
@@ -200,6 +214,25 @@ dependencies = [
  "syn 2.0.28",
 ]
 
+[[package]]
+name = "strum"
+version = "0.25.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "290d54ea6f91c969195bdbcd7442c8c2a2ba87da8bf60a7ee86a235d4bc1e125"
+
+[[package]]
+name = "strum_macros"
+version = "0.25.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ad8d03b598d3d0fff69bf533ee3ef19b8eeb342729596df84bcc7e1f96ec4059"
+dependencies = [
+ "heck",
+ "proc-macro2",
+ "quote",
+ "rustversion",
+ "syn 2.0.28",
+]
+
 [[package]]
 name = "syn"
 version = "1.0.109"
diff --git a/dyesub-tool/Cargo.toml b/dyesub-tool/Cargo.toml
index 1ff22f0..a67246a 100644
--- a/dyesub-tool/Cargo.toml
+++ b/dyesub-tool/Cargo.toml
@@ -6,3 +6,5 @@ edition = "2021"
 [dependencies]
 askama = "0.12.0"
 derive_more = "0.99.17"
+strum = "0.25.0"
+strum_macros = "0.25.2"
diff --git a/dyesub-tool/src/svg/unit.rs b/dyesub-tool/src/svg/unit.rs
index 9c67baf..762a535 100644
--- a/dyesub-tool/src/svg/unit.rs
+++ b/dyesub-tool/src/svg/unit.rs
@@ -1,19 +1,26 @@
-use std::fmt::{self, Display};
+use strum_macros::{Display, EnumString, IntoStaticStr};
 
 /// https://oreillymedia.github.io/Using_SVG/guide/units.html
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
+#[derive(Display, EnumString, IntoStaticStr)]
 pub enum SVGUnit {
     /// Pixel units, directly equivalent to SVG user units.
+    #[strum(serialize = "px")]
     Pixel,
     /// Inches.
+    #[strum(serialize = "in")]
     Inch,
     /// Centimeters.
+    #[strum(serialize = "cm")]
     Centimeter,
     /// Millimeters.
+    #[strum(serialize = "mm")]
     Millimeter,
     /// Points.
+    #[strum(serialize = "pt")]
     Point,
     // Picas.
+    #[strum(serialize = "pc")]
     Pica,
 }
 
@@ -29,22 +36,4 @@ impl SVGUnit {
             Pica => 16.0,
         }
     }
-}
-
-impl Display for SVGUnit {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        use SVGUnit::*;
-        write!(
-            f,
-            "{}",
-            match &self {
-                Pixel => "px",
-                Inch => "in",
-                Centimeter => "cm",
-                Millimeter => "mm",
-                Point => "pt",
-                Pica => "pc",
-            }
-        )
-    }
-}
+}
\ No newline at end of file
diff --git a/flake.nix b/flake.nix
index 98edfdf..7042f94 100644
--- a/flake.nix
+++ b/flake.nix
@@ -51,7 +51,7 @@ Updating `cargoHash`:
           pname = "dyesub-tool";
           version = "0.1.0";
           buildAndTestSubdir = "dyesub-tool";
-          cargoHash = "sha256-owoTOMY/u7K3Y96FIHXMJeqILAOFR2wSYozzsT+0p64=";
+          cargoHash = "sha256-WUA3ysG7SlylV1y5nkPxLRGVa4NktFjpawE97d3b36I=";
           meta = meta // {
             description = "A tool for generating dye sublimation transfer sheet SVGs for Japanese thumb shift 拇指シフト keycaps.";
           };