diff --git a/src/Compiler/Service/service.fsi b/src/Compiler/Service/service.fsi
index e74249cd60..83eb54137e 100644
--- a/src/Compiler/Service/service.fsi
+++ b/src/Compiler/Service/service.fsi
@@ -60,7 +60,8 @@ type public FSharpChecker =
             bool ->
             FSharpChecker
 
-    member internal UsesTransparentCompiler: bool
+    [<Experimental("This FCS API is experimental and subject to change.")>]
+    member UsesTransparentCompiler: bool
 
     /// <summary>
     ///   Parse a source code file, returning information about brace matching in the file.
diff --git a/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.debug.bsl b/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.debug.bsl
index da61adbe19..b5439121c8 100644
--- a/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.debug.bsl
+++ b/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.debug.bsl
@@ -2038,6 +2038,8 @@ FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: FSharp.Compiler.Symbols.
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String ToString()
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String[] DependencyFiles
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String[] get_DependencyFiles()
+FSharp.Compiler.CodeAnalysis.FSharpChecker: Boolean UsesTransparentCompiler
+FSharp.Compiler.CodeAnalysis.FSharpChecker: Boolean get_UsesTransparentCompiler()
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker Create(Microsoft.FSharp.Core.FSharpOption`1[System.Int32], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.CodeAnalysis.LegacyReferenceResolver], Microsoft.FSharp.Core.FSharpOption`1[Microsoft.FSharp.Core.FSharpFunc`2[System.Tuple`2[System.String,System.DateTime],Microsoft.FSharp.Core.FSharpOption`1[System.Tuple`3[System.Object,System.IntPtr,System.Int32]]]], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.CodeAnalysis.DocumentSource], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean])
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker Instance
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker get_Instance()
diff --git a/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.release.bsl b/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.release.bsl
index da61adbe19..b5439121c8 100644
--- a/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.release.bsl
+++ b/tests/FSharp.Compiler.Service.Tests/FSharp.Compiler.Service.SurfaceArea.netstandard20.release.bsl
@@ -2038,6 +2038,8 @@ FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: FSharp.Compiler.Symbols.
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String ToString()
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String[] DependencyFiles
 FSharp.Compiler.CodeAnalysis.FSharpCheckProjectResults: System.String[] get_DependencyFiles()
+FSharp.Compiler.CodeAnalysis.FSharpChecker: Boolean UsesTransparentCompiler
+FSharp.Compiler.CodeAnalysis.FSharpChecker: Boolean get_UsesTransparentCompiler()
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker Create(Microsoft.FSharp.Core.FSharpOption`1[System.Int32], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.CodeAnalysis.LegacyReferenceResolver], Microsoft.FSharp.Core.FSharpOption`1[Microsoft.FSharp.Core.FSharpFunc`2[System.Tuple`2[System.String,System.DateTime],Microsoft.FSharp.Core.FSharpOption`1[System.Tuple`3[System.Object,System.IntPtr,System.Int32]]]], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.CodeAnalysis.DocumentSource], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean], Microsoft.FSharp.Core.FSharpOption`1[System.Boolean])
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker Instance
 FSharp.Compiler.CodeAnalysis.FSharpChecker: FSharp.Compiler.CodeAnalysis.FSharpChecker get_Instance()
diff --git a/tests/service/ProjectAnalysisTests.fs b/tests/service/ProjectAnalysisTests.fs
index 8a643c9a7b..266ec0d900 100644
--- a/tests/service/ProjectAnalysisTests.fs
+++ b/tests/service/ProjectAnalysisTests.fs
@@ -7,6 +7,8 @@
 module Tests.Service.ProjectAnalysisTests
 #endif
 
+#nowarn "57" // Experimental stuff
+
 let runningOnMono = try System.Type.GetType("Mono.Runtime") <> null with e ->  false
 
 open NUnit.Framework