diff --git a/examples/simplecli.rs b/examples/simplecli.rs
index 866f96f..e2a87c5 100644
--- a/examples/simplecli.rs
+++ b/examples/simplecli.rs
@@ -162,7 +162,7 @@ fn main() {
                         .seed(seed),
                 )
             } else {
-                QuantizeMethod::Wu
+                QuantizeMethod::wu()
             };
 
             let colorspace = colorspace.into();
diff --git a/src/api/colorspace.rs b/src/api/colorspace.rs
index 64706a5..1c73572 100644
--- a/src/api/colorspace.rs
+++ b/src/api/colorspace.rs
@@ -5,11 +5,15 @@ use crate::{
     QuantizeMethod,
 };
 
+#[cfg(all(feature = "kmeans", feature = "colorspaces"))]
+use crate::kmeans::Centroids;
 #[cfg(feature = "kmeans")]
-use crate::{kmeans::Centroids, KmeansOptions};
+use crate::KmeansOptions;
 #[cfg(feature = "colorspaces")]
 use crate::{wu::FloatBinner, ColorSlice};
 
+use std::marker::PhantomData;
+
 #[cfg(feature = "colorspaces")]
 use ::palette::{IntoColor, LinSrgb, Srgb};
 #[cfg(all(feature = "threads", feature = "colorspaces"))]
@@ -149,18 +153,18 @@ where
 #[cfg(feature = "colorspaces")]
 impl QuantizeMethod<Srgb<u8>> {
     /// Convert the colorspace
+    #[allow(unused_variables)]
     pub(crate) fn convert_color_space_from_srgb<Color>(
         self,
         convert_to: impl Fn(Srgb<u8>) -> Color,
     ) -> QuantizeMethod<Color> {
         match self {
-            QuantizeMethod::Wu => QuantizeMethod::Wu,
+            QuantizeMethod::Wu(_) => QuantizeMethod::Wu(PhantomData),
             #[cfg(feature = "kmeans")]
             QuantizeMethod::Kmeans(KmeansOptions {
                 sampling_factor,
                 initial_centroids,
                 seed,
-                #[cfg(feature = "threads")]
                 batch_size,
             }) => QuantizeMethod::Kmeans(KmeansOptions {
                 initial_centroids: initial_centroids.map(|c| {
@@ -168,9 +172,23 @@ impl QuantizeMethod<Srgb<u8>> {
                 }),
                 sampling_factor,
                 seed,
-                #[cfg(feature = "threads")]
                 batch_size,
             }),
         }
     }
 }
+
+impl<Color> QuantizeMethod<Color> {
+    /// Creates a new [`QuantizeMethod::Wu`].
+    #[must_use]
+    pub const fn wu() -> Self {
+        Self::Wu(PhantomData)
+    }
+
+    /// Creates a new [`QuantizeMethod::Kmeans`] with the default [`KmeansOptions`].
+    #[must_use]
+    #[cfg(feature = "kmeans")]
+    pub const fn kmeans() -> Self {
+        Self::Kmeans(KmeansOptions::new())
+    }
+}
diff --git a/src/api/image_pipeline.rs b/src/api/image_pipeline.rs
index 0475aef..e50bbb6 100644
--- a/src/api/image_pipeline.rs
+++ b/src/api/image_pipeline.rs
@@ -4,39 +4,38 @@
 use super::num_samples;
 
 use crate::{
-    dither::FloydSteinberg, wu, ColorComponents, ColorCounts, ColorCountsRemap, ColorSlice,
-    ColorSpace, IndexedColorCounts, PalettePipeline, PaletteSize, QuantizeMethod,
+    dither::FloydSteinberg,
+    wu::{self, Binner3},
+    ColorComponents, ColorCounts, ColorCountsRemap, ColorSlice, ColorSpace, PalettePipeline,
+    PaletteSize, QuantizeMethod, SumPromotion, ZeroedIsZero,
 };
 
 #[cfg(all(feature = "colorspaces", feature = "threads"))]
 use crate::colorspace::convert_color_slice_par;
+#[cfg(feature = "colorspaces")]
+use crate::colorspace::{convert_color_slice, from_srgb, to_srgb};
 #[cfg(feature = "image")]
 use crate::AboveMaxLen;
 #[cfg(feature = "threads")]
 use crate::ColorCountsParallelRemap;
-#[cfg(feature = "colorspaces")]
-use crate::{
-    colorspace::{convert_color_slice, from_srgb, to_srgb},
-    wu::Binner3,
-    SumPromotion, ZeroedIsZero,
-};
+#[cfg(any(feature = "colorspaces", feature = "kmeans"))]
+use crate::IndexedColorCounts;
 #[cfg(feature = "kmeans")]
 use crate::{
     kmeans::{self, Centroids},
     KmeansOptions,
 };
 
+use num_traits::AsPrimitive;
 use palette::Srgb;
 
 #[cfg(feature = "image")]
 use image::RgbImage;
-#[cfg(feature = "colorspaces")]
-use num_traits::AsPrimitive;
 #[cfg(feature = "image")]
 use palette::cast::IntoComponents;
 #[cfg(feature = "colorspaces")]
 use palette::{Lab, Oklab};
-#[cfg(feature = "threads")]
+#[cfg(all(feature = "threads", feature = "image"))]
 use rayon::prelude::*;
 
 /// A builder struct to specify options to create a quantized image or an indexed palette from an image.
@@ -125,6 +124,7 @@ pub struct ImagePipeline<'a> {
     /// The error diffusion factor to use when dithering.
     pub(crate) dither_error_diffusion: f32,
     /// Whether or not to deduplicate the input pixels/colors.
+    #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
     pub(crate) dedup_pixels: bool,
 }
 
@@ -137,9 +137,10 @@ impl<'a> ImagePipeline<'a> {
             dimensions: (width, height),
             k: PaletteSize::default(),
             colorspace: ColorSpace::Srgb,
-            quantize_method: QuantizeMethod::Wu,
+            quantize_method: QuantizeMethod::wu(),
             dither: true,
             dither_error_diffusion: FloydSteinberg::DEFAULT_ERROR_DIFFUSION,
+            #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
             dedup_pixels: true,
         }
     }
@@ -274,6 +275,7 @@ impl<'a> ImagePipeline<'a> {
                     colors,
                     k,
                     quantize_method,
+                    #[cfg(feature = "kmeans")]
                     dedup_pixels,
                     dimensions,
                     ..
@@ -414,6 +416,7 @@ impl<'a> ImagePipeline<'a> {
                     colors,
                     k,
                     quantize_method,
+                    #[cfg(feature = "kmeans")]
                     dedup_pixels,
                     dimensions,
                     ..
@@ -539,6 +542,7 @@ impl<'a> ImagePipeline<'a> {
 }
 
 /// Computes a color palette and the indices into it.
+#[allow(clippy::needless_pass_by_value)]
 fn indexed_palette<Color, Component, const B: usize>(
     color_counts: &impl ColorCountsRemap<Color, Component, 3>,
     width: u32,
@@ -556,7 +560,7 @@ where
     f32: AsPrimitive<Component>,
 {
     let (palette, mut indices) = match method {
-        QuantizeMethod::Wu => {
+        QuantizeMethod::Wu(_) => {
             let res = wu::indexed_palette(color_counts, k, binner);
             (res.palette, res.indices)
         }
@@ -595,6 +599,7 @@ where
 
 /// Computes a color palette and the indices into it in parallel.
 #[cfg(feature = "threads")]
+#[allow(clippy::needless_pass_by_value)]
 fn indexed_palette_par<Color, Component, const B: usize>(
     color_counts: &(impl ColorCountsParallelRemap<Color, Component, 3> + Send + Sync),
     width: u32,
@@ -612,7 +617,7 @@ where
     f32: AsPrimitive<Component>,
 {
     let (palette, mut indices) = match method {
-        QuantizeMethod::Wu => {
+        QuantizeMethod::Wu(_) => {
             let res = wu::indexed_palette_par(color_counts, k, binner);
             (res.palette, res.indices)
         }
diff --git a/src/api/mod.rs b/src/api/mod.rs
index 83a22cf..71c77ba 100644
--- a/src/api/mod.rs
+++ b/src/api/mod.rs
@@ -8,10 +8,10 @@ pub use colorspace::ColorSpace;
 pub use image_pipeline::ImagePipeline;
 pub use palette_pipeline::PalettePipeline;
 
-use crate::{ColorComponents, ColorCounts};
-
 #[cfg(feature = "kmeans")]
-use crate::kmeans::Centroids;
+use crate::{kmeans::Centroids, ColorComponents, ColorCounts};
+
+use std::marker::PhantomData;
 
 /// A builder struct to specify the parameters for k-means.
 ///
@@ -33,10 +33,11 @@ pub struct KmeansOptions<Color> {
     /// The seed value for the random number generator.
     seed: u64,
     /// The batch size for minibatch k-means.
-    #[cfg(feature = "threads")]
+    #[allow(unused)]
     batch_size: u32,
 }
 
+#[cfg(feature = "kmeans")]
 impl<Color> Default for KmeansOptions<Color> {
     fn default() -> Self {
         Self::new()
@@ -47,12 +48,11 @@ impl<Color> Default for KmeansOptions<Color> {
 impl<Color> KmeansOptions<Color> {
     /// Creates a new [`KmeansOptions`] with default values.
     #[must_use]
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         Self {
             sampling_factor: 0.5,
             initial_centroids: None,
             seed: 0,
-            #[cfg(feature = "threads")]
             batch_size: 4096,
         }
     }
@@ -129,7 +129,7 @@ pub enum QuantizeMethod<Color> {
     /// This method is quick and gives good or at least decent results.
     ///
     /// See the [`wu`](crate::wu) module for more details.
-    Wu,
+    Wu(PhantomData<Color>),
     /// Color quantization using k-means clustering.
     ///
     /// This method is slower than Wu's color quantizer but gives more accurate results.
diff --git a/src/api/palette_pipeline.rs b/src/api/palette_pipeline.rs
index e2dfdbf..f56c265 100644
--- a/src/api/palette_pipeline.rs
+++ b/src/api/palette_pipeline.rs
@@ -4,33 +4,31 @@
 use super::num_samples;
 
 use crate::{
-    wu, ColorComponents, ColorCounts, ColorSlice, ColorSpace, ImagePipeline, PaletteSize,
-    QuantizeMethod, UniqueColorCounts,
+    wu::{self, Binner3},
+    ColorComponents, ColorCounts, ColorSlice, ColorSpace, ImagePipeline, PaletteSize,
+    QuantizeMethod, SumPromotion, ZeroedIsZero,
 };
 
 #[cfg(all(feature = "colorspaces", feature = "threads"))]
 use crate::colorspace::convert_color_slice_par;
+#[cfg(feature = "colorspaces")]
+use crate::colorspace::{convert_color_slice, from_srgb, to_srgb};
 #[cfg(feature = "image")]
 use crate::AboveMaxLen;
-#[cfg(feature = "colorspaces")]
-use crate::{
-    colorspace::{convert_color_slice, from_srgb, to_srgb},
-    wu::Binner3,
-    SumPromotion, ZeroedIsZero,
-};
+#[cfg(any(feature = "colorspaces", feature = "kmeans"))]
+use crate::UniqueColorCounts;
 #[cfg(feature = "kmeans")]
 use crate::{
     kmeans::{self, Centroids},
     KmeansOptions,
 };
 
+use num_traits::AsPrimitive;
 use palette::Srgb;
 
 #[cfg(feature = "image")]
 use image::RgbImage;
 #[cfg(feature = "colorspaces")]
-use num_traits::AsPrimitive;
-#[cfg(feature = "colorspaces")]
 use palette::{Lab, Oklab};
 
 /// A builder struct to specify options to create a color palette for an image or slice of colors.
@@ -132,6 +130,7 @@ pub struct PalettePipeline<'a> {
     /// The color quantization method to use.
     pub(crate) quantize_method: QuantizeMethod<Srgb<u8>>,
     /// Whether or not to deduplicate the input pixels/colors.
+    #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
     pub(crate) dedup_pixels: bool,
 }
 
@@ -143,7 +142,8 @@ impl<'a> PalettePipeline<'a> {
             colors,
             k: PaletteSize::default(),
             colorspace: ColorSpace::Srgb,
-            quantize_method: QuantizeMethod::Wu,
+            quantize_method: QuantizeMethod::wu(),
+            #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
             dedup_pixels: true,
         }
     }
@@ -214,6 +214,7 @@ impl<'a> From<ImagePipeline<'a>> for PalettePipeline<'a> {
             k,
             colorspace,
             quantize_method,
+            #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
             dedup_pixels,
             ..
         } = value;
@@ -223,6 +224,7 @@ impl<'a> From<ImagePipeline<'a>> for PalettePipeline<'a> {
             k,
             colorspace,
             quantize_method,
+            #[cfg(any(feature = "kmeans", feature = "colorspaces"))]
             dedup_pixels,
         }
     }
@@ -235,7 +237,12 @@ impl<'a> PalettePipeline<'a> {
         match self.colorspace {
             ColorSpace::Srgb => {
                 let Self {
-                    colors, k, quantize_method, dedup_pixels, ..
+                    colors,
+                    k,
+                    quantize_method,
+                    #[cfg(feature = "kmeans")]
+                    dedup_pixels,
+                    ..
                 } = self;
 
                 match quantize_method {
@@ -315,7 +322,12 @@ impl<'a> PalettePipeline<'a> {
         match self.colorspace {
             ColorSpace::Srgb => {
                 let Self {
-                    colors, k, quantize_method, dedup_pixels, ..
+                    colors,
+                    k,
+                    quantize_method,
+                    #[cfg(feature = "kmeans")]
+                    dedup_pixels,
+                    ..
                 } = self;
 
                 match quantize_method {
@@ -390,6 +402,7 @@ impl<'a> PalettePipeline<'a> {
 }
 
 /// Computes a color palette.
+#[allow(clippy::needless_pass_by_value)]
 fn palette<Color, Component, const B: usize>(
     color_counts: &impl ColorCounts<Color, Component, 3>,
     k: PaletteSize,
@@ -404,7 +417,7 @@ where
     f32: AsPrimitive<Component>,
 {
     match method {
-        QuantizeMethod::Wu => wu::palette(color_counts, k, binner).palette,
+        QuantizeMethod::Wu(_) => wu::palette(color_counts, k, binner).palette,
         #[cfg(feature = "kmeans")]
         QuantizeMethod::Kmeans(KmeansOptions {
             sampling_factor, initial_centroids, seed, ..
@@ -422,6 +435,7 @@ where
 
 /// Computes a color palette in parallel.
 #[cfg(feature = "threads")]
+#[allow(clippy::needless_pass_by_value)]
 fn palette_par<Color, Component, const B: usize>(
     color_counts: &(impl ColorCounts<Color, Component, 3> + Send + Sync),
     k: PaletteSize,
@@ -436,7 +450,7 @@ where
     f32: AsPrimitive<Component>,
 {
     match method {
-        QuantizeMethod::Wu => wu::palette_par(color_counts, k, binner).palette,
+        QuantizeMethod::Wu(_) => wu::palette_par(color_counts, k, binner).palette,
         #[cfg(feature = "kmeans")]
         QuantizeMethod::Kmeans(KmeansOptions {
             sampling_factor,
diff --git a/src/color_counts.rs b/src/color_counts.rs
index d34a304..ccd255b 100644
--- a/src/color_counts.rs
+++ b/src/color_counts.rs
@@ -12,7 +12,7 @@ use palette::cast::{self, AsArrays};
 
 #[cfg(feature = "image")]
 use image::RgbImage;
-#[cfg(any(feature = "image", feature = "colorspaces"))]
+#[cfg(feature = "image")]
 use palette::Srgb;
 #[cfg(feature = "threads")]
 use rayon::prelude::*;
diff --git a/src/dither.rs b/src/dither.rs
index cdff952..063a078 100644
--- a/src/dither.rs
+++ b/src/dither.rs
@@ -18,8 +18,8 @@ impl FloydSteinberg {
 
     /// Creates a new [`FloydSteinberg`] with the default error diffusion factor.
     #[must_use]
-    pub fn new() -> Self {
-        Self::default()
+    pub const fn new() -> Self {
+        Self(Self::DEFAULT_ERROR_DIFFUSION)
     }
 
     /// Creates a new [`FloydSteinberg`] with the given error diffusion factor.
@@ -46,7 +46,7 @@ impl FloydSteinberg {
 
 impl Default for FloydSteinberg {
     fn default() -> Self {
-        Self(Self::DEFAULT_ERROR_DIFFUSION)
+        Self::new()
     }
 }
 
diff --git a/src/kmeans.rs b/src/kmeans.rs
index 78349dc..d450209 100644
--- a/src/kmeans.rs
+++ b/src/kmeans.rs
@@ -69,6 +69,7 @@ impl<Color> Centroids<Color> {
 
     /// Creates a [`Centroids`] without ensuring that its length
     /// is less than or equal to [`MAX_COLORS`].
+    #[allow(unused)]
     pub(crate) fn new_unchecked(centroids: Vec<Color>) -> Self {
         Self(centroids)
     }