1 files changed, 1 insertions, 1 deletions

diff --git a/src/WixToolset.Extensibility/Data/ICompileContext.cs b/src/WixToolset.Extensibility/Data/ICompileContext.cs
index a86fee1a..2ee8f2a1 100644
--- a/src/WixToolset.Extensibility/Data/ICompileContext.cs
+++ b/src/WixToolset.Extensibility/Data/ICompileContext.cs
@@ -26,7 +26,7 @@ namespace WixToolset.Extensibility.Data
         /// <summary>
         /// Set of extensions provided to the compiler.
         /// </summary>
-        IEnumerable<ICompilerExtension> Extensions { get; set; }
+        IReadOnlyCollection<ICompilerExtension> Extensions { get; set; }
 
         /// <summary>
         /// Gets or sets the platform which the compiler will use when defaulting 64-bit attributes and elements.