diff --git a/src/AzureMapsControl.Components/Atlas/Expression.cs b/src/AzureMapsControl.Components/Atlas/Expression.cs
index 4ec7b29..a487461 100644
--- a/src/AzureMapsControl.Components/Atlas/Expression.cs
+++ b/src/AzureMapsControl.Components/Atlas/Expression.cs
@@ -167,7 +167,7 @@ private void WriteExpressionOrNumber(Utf8JsonWriter writer, ExpressionOrNumber v
 
         private void WriteExpressionOrStringArray(Utf8JsonWriter writer, ExpressionOrStringArray value)
         {
-            if (value.Values.Any())
+            if (value.Values is not null)
             {
                 writer.WriteStartArray();
                 foreach (var expression in value.Values)
diff --git a/tests/AzureMapsControl.Components.Tests/Animations/Options/Easing.cs b/tests/AzureMapsControl.Components.Tests/Animations/Options/Easing.cs
index 3477c59..aae91b4 100644
--- a/tests/AzureMapsControl.Components.Tests/Animations/Options/Easing.cs
+++ b/tests/AzureMapsControl.Components.Tests/Animations/Options/Easing.cs
@@ -1,5 +1,6 @@
 namespace AzureMapsControl.Components.Tests.Animations.Options
 {
+
     using AzureMapsControl.Components.Animations.Options;
 
     using Xunit;
@@ -38,14 +39,14 @@ public class EasingTests
         [InlineData("easeInBounce")]
         [InlineData("easeOutBounce")]
         [InlineData("easeInOutBounce")]
-        public static void Should_ReturnEasingFromString(string easingType)
+        public void Should_ReturnEasingFromString(string easingType)
         {
             var easing = Easing.FromString(easingType);
             Assert.Equal(easingType, easing.ToString());
         }
 
         [Fact]
-        public static void Should_ReturnDefaultEasing_IfStringDoesNotMatch()
+        public void Should_ReturnDefaultEasing_IfStringDoesNotMatch()
         {
             var easingType = "obviouslyNotAValidOne";
             var easing = Easing.FromString(easingType);
diff --git a/tests/AzureMapsControl.Components.Tests/Atlas/Expression.cs b/tests/AzureMapsControl.Components.Tests/Atlas/Expression.cs
new file mode 100644
index 0000000..d5d15b7
--- /dev/null
+++ b/tests/AzureMapsControl.Components.Tests/Atlas/Expression.cs
@@ -0,0 +1,326 @@
+namespace AzureMapsControl.Components.Tests.Atlas
+{
+    using System;
+    using System.Buffers;
+    using System.Text;
+    using System.Text.Json;
+
+    using AzureMapsControl.Components.Atlas;
+
+    using Xunit;
+
+    public class ExpressionJsonConverterTests
+    {
+        [Fact]
+        public void Should_WriteJson()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var expression = new Expression(JsonDocument.Parse(json));
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes(json);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteExpressions()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var child = new Expression(JsonDocument.Parse(json));
+            var expression = new Expression(new[] { child });
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedJson = "[[\"get\",\"Confirmed\"]]";
+            var expectedBytes = Encoding.UTF8.GetBytes(expectedJson);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+    }
+
+    public class ExpressionOrNumberJsonConverterTests
+    {
+        [Fact]
+        public void Should_WriteJson()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var expression = new ExpressionOrNumber(JsonDocument.Parse(json));
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrNumberJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes(json);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteExpressions()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var child = new Expression(JsonDocument.Parse(json));
+            var expression = new ExpressionOrNumber(new[] { child });
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrNumberJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedJson = "[[\"get\",\"Confirmed\"]]";
+            var expectedBytes = Encoding.UTF8.GetBytes(expectedJson);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteNumberValue()
+        {
+            var value = 1;
+            var expression = new ExpressionOrNumber(value);
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrNumberJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes(value.ToString());
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_NotWriteNumberValue()
+        {
+            double? value = null;
+            var expression = new ExpressionOrNumber(value);
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrNumberJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            Assert.Equal(0, buffer.WrittenCount);
+        }
+    }
+
+    public class ExpressionOrStringJsonConverterTests
+    {
+        [Fact]
+        public void Should_WriteJson()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var expression = new ExpressionOrString(JsonDocument.Parse(json));
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes(json);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteExpressions()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var child = new Expression(JsonDocument.Parse(json));
+            var expression = new ExpressionOrString(new[] { child });
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedJson = "[[\"get\",\"Confirmed\"]]";
+            var expectedBytes = Encoding.UTF8.GetBytes(expectedJson);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteStringValue()
+        {
+            var value = "value";
+            var expression = new ExpressionOrString(value);
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes("\"" + value.ToString() + "\"");
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+    }
+
+    public class ExpressionOrStringArrayConverterTests
+    {
+        [Fact]
+        public void Should_WriteJson()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var expression = new ExpressionOrStringArray(JsonDocument.Parse(json));
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringArrayJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes(json);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteExpressions()
+        {
+            var json = "[\"get\",\"Confirmed\"]";
+            var child = new Expression(JsonDocument.Parse(json));
+            var expression = new ExpressionOrStringArray(new[] { child });
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringArrayJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedJson = "[[\"get\",\"Confirmed\"]]";
+            var expectedBytes = Encoding.UTF8.GetBytes(expectedJson);
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_WriteStringArray()
+        {
+            var value = "value";
+            var expression = new ExpressionOrStringArray(new[] { value });
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringArrayJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes("[\"" + value.ToString() + "\"]");
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+
+        [Fact]
+        public void Should_NotWriteStringArray_NullCase()
+        {
+            string[] values = null;
+            var expression = new ExpressionOrStringArray(values);
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringArrayJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            Assert.Equal(0, buffer.WrittenCount);
+        }
+
+        [Fact]
+        public void Should_WriteStringArray_EmptyCase()
+        {
+            var expression = new ExpressionOrStringArray(Array.Empty<string>());
+            var buffer = new ArrayBufferWriter<byte>();
+            using var writer = new Utf8JsonWriter(buffer);
+
+            var converter = new ExpressionOrStringArrayJsonConverter();
+            converter.Write(writer, expression, null);
+
+            writer.Flush();
+
+            var expectedBytes = Encoding.UTF8.GetBytes("[]");
+
+            var expectedBytesSet = new System.Collections.Generic.HashSet<byte>(expectedBytes);
+            var writterSet = new System.Collections.Generic.HashSet<byte>(buffer.WrittenSpan.ToArray());
+
+            Assert.Equal(expectedBytes.Length, buffer.WrittenCount);
+            Assert.Subset(expectedBytesSet, writterSet);
+        }
+    }
+}