diff --git a/src/ImageSharp/ColorSpaces/CieLab.cs b/src/ImageSharp/ColorSpaces/CieLab.cs
index 107be4cb2..cb08d08bf 100644
--- a/src/ImageSharp/ColorSpaces/CieLab.cs
+++ b/src/ImageSharp/ColorSpaces/CieLab.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents a CIE L*a*b* 1976 color.
     /// <see href="https://en.wikipedia.org/wiki/Lab_color_space"/>
     /// </summary>
-    internal struct CieLab : IColorVector, IEquatable<CieLab>, IAlmostEquatable<CieLab, float>
+    internal readonly struct CieLab : IColorVector, IEquatable<CieLab>, IAlmostEquatable<CieLab, float>
     {
         /// <summary>
         /// D50 standard illuminant.
diff --git a/src/ImageSharp/ColorSpaces/CieLch.cs b/src/ImageSharp/ColorSpaces/CieLch.cs
index 834ef56a8..94443fd86 100644
--- a/src/ImageSharp/ColorSpaces/CieLch.cs
+++ b/src/ImageSharp/ColorSpaces/CieLch.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents the CIE L*C*h°, cylindrical form of the CIE L*a*b* 1976 color.
     /// <see href="https://en.wikipedia.org/wiki/Lab_color_space#Cylindrical_representation:_CIELCh_or_CIEHLC"/>
     /// </summary>
-    internal struct CieLch : IColorVector, IEquatable<CieLch>, IAlmostEquatable<CieLch, float>
+    internal readonly struct CieLch : IColorVector, IEquatable<CieLch>, IAlmostEquatable<CieLch, float>
     {
         /// <summary>
         /// D50 standard illuminant.
diff --git a/src/ImageSharp/ColorSpaces/CieLchuv.cs b/src/ImageSharp/ColorSpaces/CieLchuv.cs
index f35914d64..705b770d3 100644
--- a/src/ImageSharp/ColorSpaces/CieLchuv.cs
+++ b/src/ImageSharp/ColorSpaces/CieLchuv.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents the CIE L*C*h°, cylindrical form of the CIE L*u*v* 1976 color.
     /// <see href="https://en.wikipedia.org/wiki/Lab_color_space#Cylindrical_representation:_CieLchuv_or_CIEHLC"/>
     /// </summary>
-    internal struct CieLchuv : IColorVector, IEquatable<CieLchuv>, IAlmostEquatable<CieLchuv, float>
+    internal readonly struct CieLchuv : IColorVector, IEquatable<CieLchuv>, IAlmostEquatable<CieLchuv, float>
     {
         /// <summary>
         /// D50 standard illuminant.
diff --git a/src/ImageSharp/ColorSpaces/CieLuv.cs b/src/ImageSharp/ColorSpaces/CieLuv.cs
index 9b5251708..b0ae048ab 100644
--- a/src/ImageSharp/ColorSpaces/CieLuv.cs
+++ b/src/ImageSharp/ColorSpaces/CieLuv.cs
@@ -14,7 +14,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// attempted perceptual uniformity
     /// <see href="https://en.wikipedia.org/wiki/CIELUV"/>
     /// </summary>
-    internal struct CieLuv : IColorVector, IEquatable<CieLuv>, IAlmostEquatable<CieLuv, float>
+    internal readonly struct CieLuv : IColorVector, IEquatable<CieLuv>, IAlmostEquatable<CieLuv, float>
     {
         /// <summary>
         /// D65 standard illuminant.
diff --git a/src/ImageSharp/ColorSpaces/CieXyChromaticityCoordinates.cs b/src/ImageSharp/ColorSpaces/CieXyChromaticityCoordinates.cs
index 487f464d8..d0a70dd19 100644
--- a/src/ImageSharp/ColorSpaces/CieXyChromaticityCoordinates.cs
+++ b/src/ImageSharp/ColorSpaces/CieXyChromaticityCoordinates.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents the coordinates of CIEXY chromaticity space
     /// </summary>
-    internal struct CieXyChromaticityCoordinates : IEquatable<CieXyChromaticityCoordinates>, IAlmostEquatable<CieXyChromaticityCoordinates, float>
+    internal readonly struct CieXyChromaticityCoordinates : IEquatable<CieXyChromaticityCoordinates>, IAlmostEquatable<CieXyChromaticityCoordinates, float>
     {
         /// <summary>
         /// Represents a <see cref="CieXyChromaticityCoordinates"/> that has X, Y values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/CieXyy.cs b/src/ImageSharp/ColorSpaces/CieXyy.cs
index d5ef4b15d..751830a0b 100644
--- a/src/ImageSharp/ColorSpaces/CieXyy.cs
+++ b/src/ImageSharp/ColorSpaces/CieXyy.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents an CIE xyY 1931 color
     /// <see href="https://en.wikipedia.org/wiki/CIE_1931_color_space#CIE_xy_chromaticity_diagram_and_the_CIE_xyY_color_space"/>
     /// </summary>
-    internal struct CieXyy : IColorVector, IEquatable<CieXyy>, IAlmostEquatable<CieXyy, float>
+    internal readonly struct CieXyy : IColorVector, IEquatable<CieXyy>, IAlmostEquatable<CieXyy, float>
     {
         /// <summary>
         /// Represents a <see cref="CieXyy"/> that has X, Y, and Y values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/CieXyz.cs b/src/ImageSharp/ColorSpaces/CieXyz.cs
index 908408000..0f1866009 100644
--- a/src/ImageSharp/ColorSpaces/CieXyz.cs
+++ b/src/ImageSharp/ColorSpaces/CieXyz.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents an CIE XYZ 1931 color
     /// <see href="https://en.wikipedia.org/wiki/CIE_1931_color_space#Definition_of_the_CIE_XYZ_color_space"/>
     /// </summary>
-    internal struct CieXyz : IColorVector, IEquatable<CieXyz>, IAlmostEquatable<CieXyz, float>
+    internal readonly struct CieXyz : IColorVector, IEquatable<CieXyz>, IAlmostEquatable<CieXyz, float>
     {
         /// <summary>
         /// Represents a <see cref="CieXyz"/> that has X, Y, and Z values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/Cmyk.cs b/src/ImageSharp/ColorSpaces/Cmyk.cs
index 2a58a5762..2eb148a8c 100644
--- a/src/ImageSharp/ColorSpaces/Cmyk.cs
+++ b/src/ImageSharp/ColorSpaces/Cmyk.cs
@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents an CMYK (cyan, magenta, yellow, keyline) color.
     /// </summary>
-    internal struct Cmyk : IEquatable<Cmyk>, IAlmostEquatable<Cmyk, float>
+    internal readonly struct Cmyk : IEquatable<Cmyk>, IAlmostEquatable<Cmyk, float>
     {
         /// <summary>
         /// Represents a <see cref="Cmyk"/> that has C, M, Y, and K values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/Conversion/Implementation/Rgb/RgbWorkingSpace.cs b/src/ImageSharp/ColorSpaces/Conversion/Implementation/Rgb/RgbWorkingSpace.cs
index 8a2c66a80..5a5c39647 100644
--- a/src/ImageSharp/ColorSpaces/Conversion/Implementation/Rgb/RgbWorkingSpace.cs
+++ b/src/ImageSharp/ColorSpaces/Conversion/Implementation/Rgb/RgbWorkingSpace.cs
@@ -6,7 +6,7 @@ namespace SixLabors.ImageSharp.ColorSpaces.Conversion.Implementation.RgbColorSap
     /// <summary>
     /// Trivial implementation of <see cref="IRgbWorkingSpace"/>
     /// </summary>
-    internal struct RgbWorkingSpace : IRgbWorkingSpace
+    internal readonly struct RgbWorkingSpace : IRgbWorkingSpace
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="RgbWorkingSpace"/> struct.
diff --git a/src/ImageSharp/ColorSpaces/Hsl.cs b/src/ImageSharp/ColorSpaces/Hsl.cs
index cf880f154..1944ac0c6 100644
--- a/src/ImageSharp/ColorSpaces/Hsl.cs
+++ b/src/ImageSharp/ColorSpaces/Hsl.cs
@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents a Hsl (hue, saturation, lightness) color.
     /// </summary>
-    internal struct Hsl : IColorVector, IEquatable<Hsl>, IAlmostEquatable<Hsl, float>
+    internal readonly struct Hsl : IColorVector, IEquatable<Hsl>, IAlmostEquatable<Hsl, float>
     {
         /// <summary>
         /// Represents a <see cref="Hsl"/> that has H, S, and L values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/Hsv.cs b/src/ImageSharp/ColorSpaces/Hsv.cs
index 9f4739379..45ffd7f12 100644
--- a/src/ImageSharp/ColorSpaces/Hsv.cs
+++ b/src/ImageSharp/ColorSpaces/Hsv.cs
@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents a HSV (hue, saturation, value) color. Also known as HSB (hue, saturation, brightness).
     /// </summary>
-    internal struct Hsv : IColorVector, IEquatable<Hsv>, IAlmostEquatable<Hsv, float>
+    internal readonly struct Hsv : IColorVector, IEquatable<Hsv>, IAlmostEquatable<Hsv, float>
     {
         /// <summary>
         /// Represents a <see cref="Hsv"/> that has H, S, and V values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/HunterLab.cs b/src/ImageSharp/ColorSpaces/HunterLab.cs
index b5ba7c86c..de42518d7 100644
--- a/src/ImageSharp/ColorSpaces/HunterLab.cs
+++ b/src/ImageSharp/ColorSpaces/HunterLab.cs
@@ -12,7 +12,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// Represents an Hunter LAB color.
     /// <see href="https://en.wikipedia.org/wiki/Lab_color_space"/>
     /// </summary>
-    internal struct HunterLab : IColorVector, IEquatable<HunterLab>, IAlmostEquatable<HunterLab, float>
+    internal readonly struct HunterLab : IColorVector, IEquatable<HunterLab>, IAlmostEquatable<HunterLab, float>
     {
         /// <summary>
         /// D50 standard illuminant.
diff --git a/src/ImageSharp/ColorSpaces/LinearRgb.cs b/src/ImageSharp/ColorSpaces/LinearRgb.cs
index 07889c352..b8c446285 100644
--- a/src/ImageSharp/ColorSpaces/LinearRgb.cs
+++ b/src/ImageSharp/ColorSpaces/LinearRgb.cs
@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents an linear Rgb color with specified <see cref="IRgbWorkingSpace"/> working space
     /// </summary>
-    internal struct LinearRgb : IColorVector, IEquatable<LinearRgb>, IAlmostEquatable<LinearRgb, float>
+    internal readonly struct LinearRgb : IColorVector, IEquatable<LinearRgb>, IAlmostEquatable<LinearRgb, float>
     {
         /// <summary>
         /// Represents a <see cref="LinearRgb"/> that has R, G, and B values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/Lms.cs b/src/ImageSharp/ColorSpaces/Lms.cs
index 82c291de3..72ac16f21 100644
--- a/src/ImageSharp/ColorSpaces/Lms.cs
+++ b/src/ImageSharp/ColorSpaces/Lms.cs
@@ -13,7 +13,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// named after their responsivity (sensitivity) at long, medium and short wavelengths.
     /// <see href="https://en.wikipedia.org/wiki/LMS_color_space"/>
     /// </summary>
-    internal struct Lms : IColorVector, IEquatable<Lms>, IAlmostEquatable<Lms, float>
+    internal readonly struct Lms : IColorVector, IEquatable<Lms>, IAlmostEquatable<Lms, float>
     {
         /// <summary>
         /// Represents a <see cref="Lms"/> that has L, M, and S values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/Rgb.cs b/src/ImageSharp/ColorSpaces/Rgb.cs
index 8ac8411b2..53fa6086d 100644
--- a/src/ImageSharp/ColorSpaces/Rgb.cs
+++ b/src/ImageSharp/ColorSpaces/Rgb.cs
@@ -11,7 +11,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <summary>
     /// Represents an RGB color with specified <see cref="IRgbWorkingSpace"/> working space
     /// </summary>
-    internal struct Rgb : IColorVector, IEquatable<Rgb>, IAlmostEquatable<Rgb, float>
+    internal readonly struct Rgb : IColorVector, IEquatable<Rgb>, IAlmostEquatable<Rgb, float>
     {
         /// <summary>
         /// Represents a <see cref="Rgb"/> that has R, G, and B values set to zero.
diff --git a/src/ImageSharp/ColorSpaces/YCbCr.cs b/src/ImageSharp/ColorSpaces/YCbCr.cs
index 708a74308..44a0b245d 100644
--- a/src/ImageSharp/ColorSpaces/YCbCr.cs
+++ b/src/ImageSharp/ColorSpaces/YCbCr.cs
@@ -13,7 +13,7 @@ namespace SixLabors.ImageSharp.ColorSpaces
     /// <see href="http://en.wikipedia.org/wiki/YCbCr"/>
     /// <see href="http://www.ijg.org/files/T-REC-T.871-201105-I!!PDF-E.pdf"/>
     /// </summary>
-    internal struct YCbCr : IColorVector, IEquatable<YCbCr>, IAlmostEquatable<YCbCr, float>
+    internal readonly struct YCbCr : IColorVector, IEquatable<YCbCr>, IAlmostEquatable<YCbCr, float>
     {
         /// <summary>
         /// Represents a <see cref="YCbCr"/> that has Y, Cb, and Cr values set to zero.
diff --git a/src/ImageSharp/Formats/Gif/PackedField.cs b/src/ImageSharp/Formats/Gif/PackedField.cs
index 962e2082b..28a415e2b 100644
--- a/src/ImageSharp/Formats/Gif/PackedField.cs
+++ b/src/ImageSharp/Formats/Gif/PackedField.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.Formats.Gif
     /// Represents a byte of data in a GIF data stream which contains a number
     /// of data items.
     /// </summary>
-    internal struct PackedField : IEquatable<PackedField>
+    internal readonly struct PackedField : IEquatable<PackedField>
     {
         /// <summary>
         /// The individual bits representing the packed byte.
diff --git a/src/ImageSharp/Formats/Jpeg/Common/Decoder/AdobeMarker.cs b/src/ImageSharp/Formats/Jpeg/Common/Decoder/AdobeMarker.cs
index 0ec2297d7..d55e36bd4 100644
--- a/src/ImageSharp/Formats/Jpeg/Common/Decoder/AdobeMarker.cs
+++ b/src/ImageSharp/Formats/Jpeg/Common/Decoder/AdobeMarker.cs
@@ -10,7 +10,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Common.Decoder
     /// Provides information about the Adobe marker segment.
     /// </summary>
     /// <remarks>See the included 5116.DCT.pdf file in the source for more information.</remarks>
-    internal struct AdobeMarker : IEquatable<AdobeMarker>
+    internal readonly struct AdobeMarker : IEquatable<AdobeMarker>
     {
         /// <summary>
         /// Gets the length of an adobe marker segment.
diff --git a/src/ImageSharp/Formats/Jpeg/Common/Decoder/JFifMarker.cs b/src/ImageSharp/Formats/Jpeg/Common/Decoder/JFifMarker.cs
index cba7be553..c856fd04a 100644
--- a/src/ImageSharp/Formats/Jpeg/Common/Decoder/JFifMarker.cs
+++ b/src/ImageSharp/Formats/Jpeg/Common/Decoder/JFifMarker.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Common.Decoder
     /// Provides information about the JFIF marker segment
     /// TODO: Thumbnail?
     /// </summary>
-    internal struct JFifMarker : IEquatable<JFifMarker>
+    internal readonly struct JFifMarker : IEquatable<JFifMarker>
     {
         /// <summary>
         /// Gets the length of an JFIF marker segment.
diff --git a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Decoder/InputProcessor.cs b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Decoder/InputProcessor.cs
index 88599808f..fd6a7833a 100644
--- a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Decoder/InputProcessor.cs
+++ b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Decoder/InputProcessor.cs
@@ -5,8 +5,6 @@ using System;
 using System.IO;
 using System.Runtime.CompilerServices;
 
-using SixLabors.ImageSharp.Memory;
-
 namespace SixLabors.ImageSharp.Formats.Jpeg.GolangPort.Components.Decoder
 {
     /// <summary>
diff --git a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanLut.cs b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanLut.cs
index 2fb01c5c8..7756a7e3b 100644
--- a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanLut.cs
+++ b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanLut.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.GolangPort.Components.Encoder
     /// codeword size in bits and the 24 least significant bits hold the codeword.
     /// The maximum codeword size is 16 bits.
     /// </summary>
-    internal struct HuffmanLut
+    internal readonly struct HuffmanLut
     {
         /// <summary>
         /// The compiled representations of theHuffmanSpec.
diff --git a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanSpec.cs b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanSpec.cs
index 8e40cb368..1c8228aaa 100644
--- a/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanSpec.cs
+++ b/src/ImageSharp/Formats/Jpeg/GolangPort/Components/Encoder/HuffmanSpec.cs
@@ -6,7 +6,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.GolangPort.Components.Encoder
     /// <summary>
     ///     The Huffman encoding specifications.
     /// </summary>
-    internal struct HuffmanSpec
+    internal readonly struct HuffmanSpec
     {
 #pragma warning disable SA1118 // ParameterMustNotSpanMultipleLines
 
diff --git a/src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/PdfJsYCbCrToRgbTables.cs b/src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/PdfJsYCbCrToRgbTables.cs
index ddc577270..203a7b1eb 100644
--- a/src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/PdfJsYCbCrToRgbTables.cs
+++ b/src/ImageSharp/Formats/Jpeg/PdfJsPort/Components/PdfJsYCbCrToRgbTables.cs
@@ -10,7 +10,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.PdfJsPort.Components
     /// Provides 8-bit lookup tables for converting from YCbCr to Rgb colorspace.
     /// Methods to build the tables are based on libjpeg implementation.
     /// </summary>
-    internal struct PdfJsYCbCrToRgbTables
+    internal readonly struct PdfJsYCbCrToRgbTables
     {
         /// <summary>
         /// The red red-chrominance table
diff --git a/src/ImageSharp/Memory/BufferArea{T}.cs b/src/ImageSharp/Memory/BufferArea{T}.cs
index 588eae483..990b494fc 100644
--- a/src/ImageSharp/Memory/BufferArea{T}.cs
+++ b/src/ImageSharp/Memory/BufferArea{T}.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.Memory
     /// This type is kind-of 2D Span, but it can live on heap.
     /// </summary>
     /// <typeparam name="T">The element type</typeparam>
-    internal struct BufferArea<T>
+    internal readonly struct BufferArea<T>
         where T : struct
     {
         /// <summary>
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccColorantTableEntry.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccColorantTableEntry.cs
index 17127110d..c5b005ea0 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccColorantTableEntry.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccColorantTableEntry.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// Entry of ICC colorant table
     /// </summary>
-    internal struct IccColorantTableEntry : IEquatable<IccColorantTableEntry>
+    internal readonly struct IccColorantTableEntry : IEquatable<IccColorantTableEntry>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccColorantTableEntry"/> struct.
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccNamedColor.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccNamedColor.cs
index 98107e828..22916c134 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccNamedColor.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccNamedColor.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// A specific color with a name
     /// </summary>
-    internal struct IccNamedColor : IEquatable<IccNamedColor>
+    internal readonly struct IccNamedColor : IEquatable<IccNamedColor>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccNamedColor"/> struct.
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccPositionNumber.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccPositionNumber.cs
index 6258ca2f3..d886dc099 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccPositionNumber.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccPositionNumber.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// Position of an object within an ICC profile
     /// </summary>
-    internal struct IccPositionNumber : IEquatable<IccPositionNumber>
+    internal readonly struct IccPositionNumber : IEquatable<IccPositionNumber>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccPositionNumber"/> struct.
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccProfileId.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccProfileId.cs
index 1f96540df..4070f835d 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccProfileId.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccProfileId.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// ICC Profile ID
     /// </summary>
-    public struct IccProfileId : IEquatable<IccProfileId>
+    public readonly struct IccProfileId : IEquatable<IccProfileId>
     {
         /// <summary>
         /// A profile ID with all values set to zero
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccResponseNumber.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccResponseNumber.cs
index a10c55f4e..c786a0fd4 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccResponseNumber.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccResponseNumber.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// Associates a normalized device code with a measurement value
     /// </summary>
-    internal struct IccResponseNumber : IEquatable<IccResponseNumber>
+    internal readonly struct IccResponseNumber : IEquatable<IccResponseNumber>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccResponseNumber"/> struct.
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccScreeningChannel.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccScreeningChannel.cs
index f41858f30..e1f1bb32f 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccScreeningChannel.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccScreeningChannel.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// A single channel of a <see cref="IccScreeningTagDataEntry"/>
     /// </summary>
-    internal struct IccScreeningChannel : IEquatable<IccScreeningChannel>
+    internal readonly struct IccScreeningChannel : IEquatable<IccScreeningChannel>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccScreeningChannel"/> struct.
diff --git a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccTagTableEntry.cs b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccTagTableEntry.cs
index 5464de9c5..7cb5c7901 100644
--- a/src/ImageSharp/MetaData/Profiles/ICC/Various/IccTagTableEntry.cs
+++ b/src/ImageSharp/MetaData/Profiles/ICC/Various/IccTagTableEntry.cs
@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
     /// <summary>
     /// Entry of ICC tag table
     /// </summary>
-    internal struct IccTagTableEntry : IEquatable<IccTagTableEntry>
+    internal readonly struct IccTagTableEntry : IEquatable<IccTagTableEntry>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="IccTagTableEntry"/> struct.
diff --git a/src/ImageSharp/Numerics/ValueSize.cs b/src/ImageSharp/Numerics/ValueSize.cs
index 659e0ebfe..fcf61a586 100644
--- a/src/ImageSharp/Numerics/ValueSize.cs
+++ b/src/ImageSharp/Numerics/ValueSize.cs
@@ -9,7 +9,7 @@ namespace SixLabors.ImageSharp
     /// <summary>
     /// Represents a value in relation to a value on the image
     /// </summary>
-    internal struct ValueSize : IEquatable<ValueSize>
+    internal readonly struct ValueSize : IEquatable<ValueSize>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="ValueSize"/> struct.
diff --git a/src/ImageSharp/Processing/Processors/Dithering/PixelPair.cs b/src/ImageSharp/Processing/Processors/Dithering/PixelPair.cs
index e3b9c11bd..07045bb5a 100644
--- a/src/ImageSharp/Processing/Processors/Dithering/PixelPair.cs
+++ b/src/ImageSharp/Processing/Processors/Dithering/PixelPair.cs
@@ -10,7 +10,7 @@ namespace SixLabors.ImageSharp.Processing.Processors
     /// Represents a composite pair of pixels. Used for caching color distance lookups.
     /// </summary>
     /// <typeparam name="TPixel">The pixel format.</typeparam>
-    internal struct PixelPair<TPixel> : IEquatable<PixelPair<TPixel>>
+    internal readonly struct PixelPair<TPixel> : IEquatable<PixelPair<TPixel>>
         where TPixel : struct, IPixel<TPixel>
     {
         /// <summary>