diff --git a/build.fsx b/build.fsx
index df8576f89d..4726a68d60 100644
--- a/build.fsx
+++ b/build.fsx
@@ -57,14 +57,14 @@ pipeline "Build" {
         run (
             cleanFolders
                 [| "bin"
-                   "src/Fantomas.FCS/bin"
-                   "src/Fantomas.FCS/obj"
-                   "src/Fantomas.Core/bin"
-                   "src/Fantomas.Core/obj"
-                   "src/Fantomas/bin"
-                   "src/Fantomas/obj"
-                   "src/Fantomas.Client/bin"
-                   "src/Fantomas.Client/obj" |]
+                   "src/Fantomas.FCS/bin/Release"
+                   "src/Fantomas.FCS/obj/Release"
+                   "src/Fantomas.Core/bin/Release"
+                   "src/Fantomas.Core/obj/Release"
+                   "src/Fantomas/bin/Release"
+                   "src/Fantomas/obj/Release"
+                   "src/Fantomas.Client/bin/Release"
+                   "src/Fantomas.Client/obj/Release" |]
         )
     }
     stage "CheckFormat" { run "dotnet fantomas src docs build.fsx --recurse --check" }
diff --git a/docs/docs/end-users/Configuration.fsx b/docs/docs/end-users/Configuration.fsx
index 837da6e679..7b90fe74fc 100644
--- a/docs/docs/end-users/Configuration.fsx
+++ b/docs/docs/end-users/Configuration.fsx
@@ -908,32 +908,6 @@ let singleList =
         ExperimentalElmish = true }
 (*** include-output ***)
 
-(**
-<fantomas-setting name="fsharp_strict_mode" red></fantomas-setting>
-
-If being set, pretty printing is only done via ASTs. Compiler directives, inline comments and block comments will be ignored.  
-There are numerous situations when the information in the AST alone cannot restore the original code.
-
-**Please do not use this setting for formatting hand written code!**
-
-Valid use-case of this settings is code generation in projects like [FsAst](https://github.com/ionide/FsAst) and [Myriad](https://github.com/MoiraeSoftware/myriad).
-
-Default = false.
-*)
-
-formatCode
-    """ 
-    // some great comment
-    let add a b =
-    #if INTERACTIVE
-        42
-    #else
-        a + b
-    #endif
-    """
-    { FormatConfig.Default with
-        StrictMode = true }
-(*** include-output ***)
 (**
 <fantomas-nav previous="./StyleGuide.html" next="./IgnoreFiles.html"></fantomas-nav>
 
diff --git a/docs/docs/end-users/UpgradeGuide.md b/docs/docs/end-users/UpgradeGuide.md
index e7828a14b8..8847d0ca07 100644
--- a/docs/docs/end-users/UpgradeGuide.md
+++ b/docs/docs/end-users/UpgradeGuide.md
@@ -66,6 +66,7 @@ fsharp_experimental_stroustrup_style = true
 - `fsharp_multiline_block_brackets_on_same_column` and `fsharp_experimental_stroustrup_style` are replaced with `fsharp_multiline_bracket_style`
 - `experimental_stroustrup` for `fsharp_multiline_bracket_style` is now `stroustrup`
 - `fsharp_newline_before_multiline_computation_expression` was extracted from `fsharp_multiline_bracket_style = stroustrup` and now controls how computation expression behave.
+- `fsharp_strict_mode` was removed and can no longer be used.
 
 ### console application
 - `-v` is now short for `--verbosity` instead of `--version`
@@ -74,5 +75,6 @@ fsharp_experimental_stroustrup_style = true
 
 ### Miscellaneous
 - The public API of CodeFormatter no longer uses `FSharpOption<'T>`, instead overloads are now used.
+- `StrictMode` was removed from `FormatConfig`, not passing the source text in the public API will have the same effect.
 
 <fantomas-nav previous="./VSCode.html" next="./FAQ.html"></fantomas-nav>
diff --git a/src/Fantomas.Core.Tests/ExternTests.fs b/src/Fantomas.Core.Tests/ExternTests.fs
index cb7f8d00d8..8d618d18fe 100644
--- a/src/Fantomas.Core.Tests/ExternTests.fs
+++ b/src/Fantomas.Core.Tests/ExternTests.fs
@@ -6,14 +6,14 @@ open Fantomas.Core.Tests.TestHelper
 
 [<Test>]
 let ``attribute above extern keyword, 562`` () =
-    formatSourceString
+    formatAST
         false
         """
 module C =
   [<DllImport("")>]
   extern IntPtr f()
 """
-        { config with StrictMode = true }
+        config
     |> prepend newline
     |> should
         equal
diff --git a/src/Fantomas.Core.Tests/InterpolatedStringTests.fs b/src/Fantomas.Core.Tests/InterpolatedStringTests.fs
index c5f333c88b..e3b20c67b1 100644
--- a/src/Fantomas.Core.Tests/InterpolatedStringTests.fs
+++ b/src/Fantomas.Core.Tests/InterpolatedStringTests.fs
@@ -63,13 +63,13 @@ let s = $\"\"\"%s{text} bar\"\"\"
 
 [<Test>]
 let ``interpolation in strict mode`` () =
-    formatSourceString
+    formatAST
         false
         """
 let text = "foo"
 let s = $"%s{text} bar"
 """
-        { config with StrictMode = true }
+        config
     |> prepend newline
     |> should
         equal
diff --git a/src/Fantomas.Core.Tests/StringTests.fs b/src/Fantomas.Core.Tests/StringTests.fs
index 38733e2569..f3297036fb 100644
--- a/src/Fantomas.Core.Tests/StringTests.fs
+++ b/src/Fantomas.Core.Tests/StringTests.fs
@@ -113,7 +113,7 @@ let g = '\n'
 
 [<Test>]
 let ``uncommon literals strict mode`` () =
-    formatSourceString
+    formatAST
         false
         """
 let a = 0xFFy
@@ -123,7 +123,7 @@ let e = 1.40e10f
 let f = 23.4M
 let g = '\n'
     """
-        { config with StrictMode = true }
+        config
     |> prepend newline
     |> should
         equal
@@ -219,14 +219,14 @@ let ``chars should be properly escaped`` () =
 
 [<Test>]
 let ``quotes should be escaped in strict mode`` () =
-    formatSourceString
+    formatAST
         false
         """
     let formatter =
         // escape commas left in invalid entries
         sprintf "%i,\"%s\""
 """
-        { config with StrictMode = true }
+        config
     |> should
         equal
         """let formatter = sprintf "%i,\"%s\""
diff --git a/src/Fantomas.Core.Tests/SynConstTests.fs b/src/Fantomas.Core.Tests/SynConstTests.fs
index 33bac8b930..f111fbd6a0 100644
--- a/src/Fantomas.Core.Tests/SynConstTests.fs
+++ b/src/Fantomas.Core.Tests/SynConstTests.fs
@@ -705,12 +705,12 @@ a:hover {color: #ecc;}
 
 [<Test>]
 let ``verbatim string in AST is preserved, 560`` () =
-    formatSourceString
+    formatAST
         false
         """
 let s = @"\"
 """
-        { config with StrictMode = true }
+        config
     |> prepend newline
     |> should
         equal
diff --git a/src/Fantomas.Core.Tests/SynLongIdentTests.fs b/src/Fantomas.Core.Tests/SynLongIdentTests.fs
index d4cfc3b519..7e0cb150fd 100644
--- a/src/Fantomas.Core.Tests/SynLongIdentTests.fs
+++ b/src/Fantomas.Core.Tests/SynLongIdentTests.fs
@@ -401,7 +401,6 @@ let ``backticks can be added from AST only scenarios`` () =
         tree,
         config =
             { config with
-                StrictMode = true
                 InsertFinalNewline = false }
     )
     |> Async.RunSynchronously
diff --git a/src/Fantomas.Core.Tests/TestHelpers.fs b/src/Fantomas.Core.Tests/TestHelpers.fs
index 562011c84c..4c65d65e2f 100644
--- a/src/Fantomas.Core.Tests/TestHelpers.fs
+++ b/src/Fantomas.Core.Tests/TestHelpers.fs
@@ -25,15 +25,24 @@ let private safeToIgnoreWarnings =
 
 let formatSourceString isFsiFile (s: string) config =
     async {
-        let! formatted =
-            if not config.StrictMode then
-                CodeFormatter.FormatDocumentAsync(isFsiFile, s, config)
-            else
-                let ast, _ =
-                    Fantomas.FCS.Parse.parseFile isFsiFile (FSharp.Compiler.Text.SourceText.ofString s) []
+        let! formatted = CodeFormatter.FormatDocumentAsync(isFsiFile, s, config)
+        let! isValid = CodeFormatter.IsValidFSharpCodeAsync(isFsiFile, formatted.Code)
 
-                CodeFormatter.FormatASTAsync(ast, config = config)
+        if not isValid then
+            failwithf $"The formatted result is not valid F# code or contains warnings\n%s{formatted.Code}"
 
+        return formatted.Code.Replace("\r\n", "\n")
+    }
+
+    |> Async.RunSynchronously
+
+/// The `source` will first be parsed to AST.
+let formatAST isFsiFile (source: string) config =
+    async {
+        let ast, _ =
+            Fantomas.FCS.Parse.parseFile isFsiFile (FSharp.Compiler.Text.SourceText.ofString source) []
+
+        let! formatted = CodeFormatter.FormatASTAsync(ast, config = config)
         let! isValid = CodeFormatter.IsValidFSharpCodeAsync(isFsiFile, formatted.Code)
 
         if not isValid then
@@ -41,7 +50,6 @@ let formatSourceString isFsiFile (s: string) config =
 
         return formatted.Code.Replace("\r\n", "\n")
     }
-
     |> Async.RunSynchronously
 
 let formatSourceStringWithDefines defines (s: string) config =
@@ -83,11 +91,6 @@ let equal x =
     equal x
 
 let inline prepend s content = s + content
-
-let formatConfig =
-    { FormatConfig.Default with
-        StrictMode = true }
-
 let (==) actual expected = Assert.AreEqual(expected, actual)
 let fail () = Assert.Fail()
 let pass () = Assert.Pass()
diff --git a/src/Fantomas.Core.Tests/UnionTests.fs b/src/Fantomas.Core.Tests/UnionTests.fs
index c3d2c99be5..9315d9e66d 100644
--- a/src/Fantomas.Core.Tests/UnionTests.fs
+++ b/src/Fantomas.Core.Tests/UnionTests.fs
@@ -203,7 +203,7 @@ let main argv =
 
 [<Test>]
 let ``enums conversion with strict mode`` () =
-    formatSourceString
+    formatAST
         false
         """
 type uColor =
@@ -211,7 +211,7 @@ type uColor =
    | Green = 1u
    | Blue = 2u
 let col3 = Microsoft.FSharp.Core.LanguagePrimitives.EnumOfValue<uint32, uColor>(2u)"""
-        { config with StrictMode = true }
+        config
     |> prepend newline
     |> should
         equal
diff --git a/src/Fantomas.Core/CodeFormatter.fs b/src/Fantomas.Core/CodeFormatter.fs
index 39d58e7042..69d1648da6 100644
--- a/src/Fantomas.Core/CodeFormatter.fs
+++ b/src/Fantomas.Core/CodeFormatter.fs
@@ -66,14 +66,14 @@ type CodeFormatter =
 
     static member FormatOakAsync(oak: Oak) : Async<string> =
         async {
-            let context = Context.Context.Create FormatConfig.Default
+            let context = Context.Context.Create false FormatConfig.Default
             let result = context |> CodePrinter.genFile oak |> Context.dump false
             return result.Code
         }
 
     static member FormatOakAsync(oak: Oak, config: FormatConfig) : Async<string> =
         async {
-            let context = Context.Context.Create config
+            let context = Context.Context.Create false config
             let result = context |> CodePrinter.genFile oak |> Context.dump false
             return result.Code
         }
diff --git a/src/Fantomas.Core/CodeFormatterImpl.fs b/src/Fantomas.Core/CodeFormatterImpl.fs
index 1ddaf29829..85edd8cd41 100644
--- a/src/Fantomas.Core/CodeFormatterImpl.fs
+++ b/src/Fantomas.Core/CodeFormatterImpl.fs
@@ -57,7 +57,7 @@ let formatAST
     (config: FormatConfig)
     (cursor: pos option)
     : FormatResult =
-    let context = Context.Context.Create config
+    let context = Context.Context.Create sourceText.IsSome config
 
     let oak =
         match sourceText with
diff --git a/src/Fantomas.Core/CodePrinter.fs b/src/Fantomas.Core/CodePrinter.fs
index 0e2eb0d0ed..1e9711bf94 100644
--- a/src/Fantomas.Core/CodePrinter.fs
+++ b/src/Fantomas.Core/CodePrinter.fs
@@ -1510,7 +1510,7 @@ let genExpr (e: Expr) =
                 |> fun ctx -> { ctx with Config = currentConfig }
             |> atCurrentColumnIndent
 
-        onlyIfCtx (fun ctx -> ctx.Config.StrictMode) (!- "$\"")
+        onlyIfCtx (fun ctx -> not ctx.HasSource) (!- "$\"")
         +> col sepNone node.Parts (fun part ->
             match part with
             | Choice1Of2 stringNode -> genSingleTextNode stringNode
@@ -1520,11 +1520,11 @@ let genExpr (e: Expr) =
                         genInterpolatedFillExpr fillNode.Expr
                         +> optSingle (fun format -> sepColonFixed +> genSingleTextNode format) fillNode.Ident
 
-                    if ctx.Config.StrictMode then
+                    if not ctx.HasSource then
                         (!- "{" +> genFill +> !- "}") ctx
                     else
                         genFill ctx)
-        +> onlyIfCtx (fun ctx -> ctx.Config.StrictMode) (!- "\"")
+        +> onlyIfCtx (fun ctx -> not ctx.HasSource) (!- "\"")
         |> genNode node
     | Expr.IndexRangeWildcard node -> genSingleTextNode node
     | Expr.TripleNumberIndexRange node ->
diff --git a/src/Fantomas.Core/Context.fs b/src/Fantomas.Core/Context.fs
index 7513f90606..c7876b4907 100644
--- a/src/Fantomas.Core/Context.fs
+++ b/src/Fantomas.Core/Context.fs
@@ -181,6 +181,7 @@ module WriterEvents =
 [<System.Diagnostics.DebuggerDisplay("\"{Dump()}\"")>]
 type Context =
     { Config: FormatConfig
+      HasSource: bool
       WriterModel: WriterModel
       WriterEvents: Queue<WriterEvent>
       FormattedCursor: pos option }
@@ -188,12 +189,15 @@ type Context =
     /// Initialize with a string writer and use space as delimiter
     static member Default =
         { Config = FormatConfig.Default
+          HasSource = false
           WriterModel = WriterModel.init
           WriterEvents = Queue.empty
           FormattedCursor = None }
 
-    static member Create config : Context =
-        { Context.Default with Config = config }
+    static member Create hasSource config : Context =
+        { Context.Default with
+            Config = config
+            HasSource = hasSource }
 
     member x.WithDummy(writerCommands, ?keepPageWidth) =
         let keepPageWidth = keepPageWidth |> Option.defaultValue false
diff --git a/src/Fantomas.Core/Context.fsi b/src/Fantomas.Core/Context.fsi
index 80e4d4921e..d54c6938c6 100644
--- a/src/Fantomas.Core/Context.fsi
+++ b/src/Fantomas.Core/Context.fsi
@@ -53,14 +53,19 @@ type WriterModel =
 
 [<System.Diagnostics.DebuggerDisplay("\"{Dump()}\"")>]
 type Context =
-    { Config: FormatConfig
-      WriterModel: WriterModel
-      WriterEvents: Queue<WriterEvent>
-      FormattedCursor: pos option }
+    {
+        Config: FormatConfig
+        /// Indicates the presence of source code.
+        /// This could be absent in the case we are formatting from AST.
+        HasSource: bool
+        WriterModel: WriterModel
+        WriterEvents: Queue<WriterEvent>
+        FormattedCursor: pos option
+    }
 
     /// Initialize with a string writer and use space as delimiter
     static member Default: Context
-    static member Create: config: FormatConfig -> Context
+    static member Create: hasSource: bool -> config: FormatConfig -> Context
     member WithDummy: writerCommands: Queue<WriterEvent> * ?keepPageWidth: bool -> Context
     member WithShortExpression: maxWidth: int * ?startColumn: int -> Context
     member Column: int
diff --git a/src/Fantomas.Core/FormatConfig.fs b/src/Fantomas.Core/FormatConfig.fs
index 10d8ce2cb5..e2abad7247 100644
--- a/src/Fantomas.Core/FormatConfig.fs
+++ b/src/Fantomas.Core/FormatConfig.fs
@@ -227,12 +227,7 @@ type FormatConfig =
 
       [<Category("Convention")>]
       [<DisplayName("Applies the Stroustrup style to the final (two) array or list argument(s) in a function application")>]
-      ExperimentalElmish: bool
-
-      [<Category("Convention")>]
-      [<DisplayName("Strict mode")>]
-      [<Description("Pretty printing based on ASTs only.\nPlease do not use this setting for formatting hand written code!")>]
-      StrictMode: bool }
+      ExperimentalElmish: bool }
 
     member x.IsStroustrupStyle = x.MultilineBracketStyle = Stroustrup
 
@@ -273,5 +268,4 @@ type FormatConfig =
           MultilineBracketStyle = Cramped
           KeepMaxNumberOfBlankLines = 100
           NewlineBeforeMultilineComputationExpression = true
-          ExperimentalElmish = false
-          StrictMode = false }
+          ExperimentalElmish = false }
diff --git a/src/Fantomas.Core/Selection.fs b/src/Fantomas.Core/Selection.fs
index c94d03ee67..1faca42e7a 100644
--- a/src/Fantomas.Core/Selection.fs
+++ b/src/Fantomas.Core/Selection.fs
@@ -402,7 +402,7 @@ let formatSelection
                 MaxLineLength = maxLineLength }
 
         let formattedSelection =
-            let context = Context.Context.Create selectionConfig
+            let context = Context.Context.Create true selectionConfig
 
             match tree with
             | TreeForSelection.Unsupported ->