diff --git a/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs b/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs
new file mode 100644
index 000000000..ffd3846bd
--- /dev/null
+++ b/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs
@@ -0,0 +1,100 @@
+using GitHub.DistributedTask.Pipelines.Expressions;
+using Xunit;
+
+namespace GitHub.Runner.Common.Tests.Sdk
+{
+    public sealed class WellKnownRegularExpressionsL0
+    {
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void SHA1_Key_Returns_CommitHash_Regex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.SHA1);
+
+            Assert.NotNull(regex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void CommitHash_Key_Returns_CommitHash_Regex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.NotNull(regex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void SHA1_And_CommitHash_Return_Same_Regex()
+        {
+            var sha1Regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.SHA1);
+            var commitHashRegex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Same(sha1Regex, commitHashRegex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_40_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Matches(regex.Value, new string((char)97, 40));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_64_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Matches(regex.Value, new string((char)97, 64));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Does_Not_Match_63_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.DoesNotMatch(regex.Value, new string((char)97, 63));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Does_Not_Match_65_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.DoesNotMatch(regex.Value, new string((char)97, 65));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_Mixed_Case_64_Char()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+            var value = new string((char)65, 32) + new string((char)98, 32);
+
+            Assert.Matches(regex.Value, value);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Unknown_Key_Returns_Null()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex("UnknownType");
+
+            Assert.Null(regex);
+        }
+    }
+}