diff --git a/Changes.md b/Changes.md
index d192ea884..b5ad535d6 100644
--- a/Changes.md
+++ b/Changes.md
@@ -134,6 +134,9 @@ Unreleased
 - Upgrade the Melange JS parser to [Flow
   v0.225.1](https://github.com/facebook/flow/releases/tag/v0.225.1)
   ([#1012](https://github.com/melange-re/melange/pull/1012))
+- fix: add a newline after `%mel.raw` expressions to avoid breaking JS output
+  when they contain single line comments
+  ([#1017](https://github.com/melange-re/melange/pull/1017))
 
 2.2.0 2023-12-05
 ---------------
diff --git a/jscomp/core/js_dump.ml b/jscomp/core/js_dump.ml
index e6cb13b79..58153629e 100644
--- a/jscomp/core/js_dump.ml
+++ b/jscomp/core/js_dump.ml
@@ -663,7 +663,9 @@ and expression_desc cxt ~(level : int) x : cxt =
           in
           if raw_paren then string cxt L.lparen;
           string cxt s;
-          if raw_paren then string cxt L.rparen;
+          if raw_paren then (
+            newline cxt;
+            string cxt L.rparen);
           cxt
       | Stmt stmt_info ->
           if stmt_info = Js_stmt_comment then string cxt s
diff --git a/jscomp/core/js_exp_make.ml b/jscomp/core/js_exp_make.ml
index 42263a11b..cd8ca59c3 100644
--- a/jscomp/core/js_exp_make.ml
+++ b/jscomp/core/js_exp_make.ml
@@ -139,7 +139,15 @@ let unicode ?loc ?comment s : t = make_expression ?loc ?comment (Unicode s)
 
 let raw_js_code ?loc ?comment info s : t =
   make_expression ?loc ?comment
-    (Raw_js_code { code = String.trim s; code_info = info })
+    (Raw_js_code
+       {
+         code =
+           (* FIXME: save one allocation
+              trim can not be done before syntax checking
+              otherwise location is incorrect *)
+           String.trim s;
+         code_info = info;
+       })
 
 let array ?loc ?comment mt es : t =
   make_expression ?loc ?comment (Array (es, mt))
diff --git a/jscomp/core/lam_compile_primitive.ml b/jscomp/core/lam_compile_primitive.ml
index 9f809266d..1f17858fb 100644
--- a/jscomp/core/lam_compile_primitive.ml
+++ b/jscomp/core/lam_compile_primitive.ml
@@ -44,12 +44,7 @@ let translate loc (cxt : Lam_compile_context.t) (prim : Lam_primitive.t)
   | Pwrap_exn ->
       E.runtime_call Js_runtime_modules.caml_js_exceptions
         "internalToOCamlException" args
-  | Praw_js_code { code; code_info } ->
-      E.raw_js_code code_info code
-      (* FIXME: save one allocation
-         trim can not be done before syntax checking
-         otherwise location is incorrect
-      *)
+  | Praw_js_code { code; code_info } -> E.raw_js_code code_info code
   | Pjs_runtime_apply -> (
       match args with [ f; args ] -> E.flat_call f args | _ -> assert false)
   | Pjs_apply -> (
diff --git a/jscomp/test/dist/jscomp/test/bs_hashtbl_string_test.js b/jscomp/test/dist/jscomp/test/bs_hashtbl_string_test.js
index 8edd36346..97be2944b 100644
--- a/jscomp/test/dist/jscomp/test/bs_hashtbl_string_test.js
+++ b/jscomp/test/dist/jscomp/test/bs_hashtbl_string_test.js
@@ -23,7 +23,8 @@ var hashString = (function(str){
                                               while(i !== 0) {
                                               hash = (hash * 33) ^ str.charCodeAt(--i);
                                               }
-                                              return hash});
+                                              return hash}
+);
 
 var $$String = Belt__Belt_Id.hashable(Stdlib__Hashtbl.hash, (function (x, y) {
         return x === y;
diff --git a/jscomp/test/dist/jscomp/test/bs_node_string_buffer_test.js b/jscomp/test/dist/jscomp/test/bs_node_string_buffer_test.js
index 00d2849c4..03afecd4c 100644
--- a/jscomp/test/dist/jscomp/test/bs_node_string_buffer_test.js
+++ b/jscomp/test/dist/jscomp/test/bs_node_string_buffer_test.js
@@ -20,7 +20,8 @@ function f(str) {
 
 f("xx");
 
-f((Buffer.from ('xx')));
+f((Buffer.from ('xx')
+    ));
 
 exports.f = f;
 /*  Not a pure module */
diff --git a/jscomp/test/dist/jscomp/test/caml_compare_test.js b/jscomp/test/dist/jscomp/test/caml_compare_test.js
index 123ba811e..4e805db10 100644
--- a/jscomp/test/dist/jscomp/test/caml_compare_test.js
+++ b/jscomp/test/dist/jscomp/test/caml_compare_test.js
@@ -999,7 +999,8 @@ var suites = {
                                                                                                 (function (param) {
                                                                                                     return {
                                                                                                             TAG: /* Eq */0,
-                                                                                                            _0: Caml_obj.caml_equal({x:1}, ((function(){let o = Object.create(null);o.x = 1;return o;})())),
+                                                                                                            _0: Caml_obj.caml_equal({x:1}, ((function(){let o = Object.create(null);o.x = 1;return o;})()
+                                                                                                                )),
                                                                                                             _1: true
                                                                                                           };
                                                                                                   })
diff --git a/jscomp/test/dist/jscomp/test/epsilon_test.js b/jscomp/test/dist/jscomp/test/epsilon_test.js
index 0e0cb4935..8c06007cf 100644
--- a/jscomp/test/dist/jscomp/test/epsilon_test.js
+++ b/jscomp/test/dist/jscomp/test/epsilon_test.js
@@ -4,7 +4,8 @@
 var Mt = require("./mt.js");
 var Stdlib = require("melange/stdlib.js");
 
-var v = (Number.EPSILON?Number.EPSILON:2.220446049250313e-16);
+var v = (Number.EPSILON?Number.EPSILON:2.220446049250313e-16
+);
 
 var suites_0 = [
   "epsilon",
diff --git a/jscomp/test/dist/jscomp/test/exception_raise_test.js b/jscomp/test/dist/jscomp/test/exception_raise_test.js
index a8af51883..4e5222398 100644
--- a/jscomp/test/dist/jscomp/test/exception_raise_test.js
+++ b/jscomp/test/dist/jscomp/test/exception_raise_test.js
@@ -64,7 +64,8 @@ var A = /* @__PURE__ */Caml_exceptions.create("Exception_raise_test.A");
 var f;
 
 try {
-  f = (function () {throw (new Error ("x"))} ());
+  f = (function () {throw (new Error ("x"))} ()
+  );
 }
 catch (raw_exn){
   var exn = Caml_js_exceptions.internalToOCamlException(raw_exn);
@@ -74,7 +75,8 @@ catch (raw_exn){
 var ff;
 
 try {
-  ff = (function () {throw 3} ());
+  ff = (function () {throw 3} ()
+  );
 }
 catch (raw_exn$1){
   var exn$1 = Caml_js_exceptions.internalToOCamlException(raw_exn$1);
@@ -84,7 +86,8 @@ catch (raw_exn$1){
 var fff;
 
 try {
-  fff = (function () {throw 2} ());
+  fff = (function () {throw 2} ()
+  );
 }
 catch (raw_exn$2){
   var exn$2 = Caml_js_exceptions.internalToOCamlException(raw_exn$2);
@@ -94,7 +97,8 @@ catch (raw_exn$2){
 var a0;
 
 try {
-  a0 = (function (){throw 2} ());
+  a0 = (function (){throw 2} ()
+  );
 }
 catch (raw_exn$3){
   var exn$3 = Caml_js_exceptions.internalToOCamlException(raw_exn$3);
@@ -116,7 +120,8 @@ catch (raw_exn$3){
 var a1;
 
 try {
-  a1 = (function (){throw 2} ());
+  a1 = (function (){throw 2} ()
+  );
 }
 catch (raw_e){
   a1 = Caml_js_exceptions.internalToOCamlException(raw_e);
@@ -125,7 +130,8 @@ catch (raw_e){
 var a2;
 
 try {
-  a2 = (function (){throw (new Error("x"))} ());
+  a2 = (function (){throw (new Error("x"))} ()
+  );
 }
 catch (raw_e$1){
   a2 = Caml_js_exceptions.internalToOCamlException(raw_e$1);
@@ -189,7 +195,8 @@ function eq(loc, x, y) {
 }
 
 try {
-  ((()=>{throw 2})());
+  ((()=>{throw 2}
+      )());
 }
 catch (raw_e$2){
   var e = Caml_js_exceptions.internalToOCamlException(raw_e$2);
@@ -236,7 +243,8 @@ function input_lines(ic, _acc) {
   };
 }
 
-eq("File \"jscomp/test/exception_raise_test.ml\", line 150, characters 5-12", ((a,b,c,_) => a + b + c)(1, 2, 3, 4), 6);
+eq("File \"jscomp/test/exception_raise_test.ml\", line 150, characters 5-12", ((a,b,c,_) => a + b + c
+      )(1, 2, 3, 4), 6);
 
 Mt.from_pair_suites("Exception_raise_test", suites.contents);
 
diff --git a/jscomp/test/dist/jscomp/test/ffi_arity_test.js b/jscomp/test/dist/jscomp/test/ffi_arity_test.js
index db8345bc6..12b5daa48 100644
--- a/jscomp/test/dist/jscomp/test/ffi_arity_test.js
+++ b/jscomp/test/dist/jscomp/test/ffi_arity_test.js
@@ -122,7 +122,8 @@ function bar(fn) {
   return Curry._1(fn, undefined);
 }
 
-(Curry._1((function(){console.log("forgiving arity")}), undefined));
+(Curry._1((function(){console.log("forgiving arity")}
+      ), undefined));
 
 exports.f = f;
 exports.v = v;
diff --git a/jscomp/test/dist/jscomp/test/ffi_js_test.js b/jscomp/test/dist/jscomp/test/ffi_js_test.js
index 5f1c12140..52c061ed2 100644
--- a/jscomp/test/dist/jscomp/test/ffi_js_test.js
+++ b/jscomp/test/dist/jscomp/test/ffi_js_test.js
@@ -3,7 +3,8 @@
 
 var Mt = require("./mt.js");
 
-var keys = (function (x){return Object.keys(x)});
+var keys = (function (x){return Object.keys(x)}
+);
 
 function $$higher_order(x){
    return function(y,z){
diff --git a/jscomp/test/dist/jscomp/test/flow_parser_reg_test.js b/jscomp/test/dist/jscomp/test/flow_parser_reg_test.js
index 7ca405ae7..cc74f1d7b 100644
--- a/jscomp/test/dist/jscomp/test/flow_parser_reg_test.js
+++ b/jscomp/test/dist/jscomp/test/flow_parser_reg_test.js
@@ -15430,15 +15430,20 @@ var translation_errors = {
   contents: /* [] */0
 };
 
-var string = (function (x) {return x;});
+var string = (function (x) {return x;}
+);
 
-var bool = (function (x) {x ? 1 : 0;});
+var bool = (function (x) {x ? 1 : 0;}
+);
 
-var obj = (function(arr) {var ret = {}; arr.forEach(function(a) {ret[a[0]]=a[1];}); return ret});
+var obj = (function(arr) {var ret = {}; arr.forEach(function(a) {ret[a[0]]=a[1];}); return ret}
+);
 
-var array = (function (x) {return x;});
+var array = (function (x) {return x;}
+);
 
-var number$1 = (function (x) {return x;});
+var number$1 = (function (x) {return x;}
+);
 
 var $$null = null;
 
diff --git a/jscomp/test/dist/jscomp/test/gpr_2682_test.js b/jscomp/test/dist/jscomp/test/gpr_2682_test.js
index 3c40cd7e0..9ba777bdb 100644
--- a/jscomp/test/dist/jscomp/test/gpr_2682_test.js
+++ b/jscomp/test/dist/jscomp/test/gpr_2682_test.js
@@ -2,7 +2,8 @@
 'use strict';
 
 
-var sum = ((a,b) => a + b);
+var sum = ((a,b) => a + b
+);
 
 var v = sum(1, 2);
 
@@ -18,7 +19,8 @@ var forIn = ((o,foo)=> {
   for (var i in o){
     foo(o)
   }
-  });
+  }
+);
 
 function log(x) {
   console.log(x);
@@ -41,7 +43,8 @@ forIn({
         console.log(x);
       }));
 
-var f3 = (()=>true);
+var f3 = (()=>true
+);
 
 var bbbb = f3();
 
diff --git a/jscomp/test/dist/jscomp/test/gpr_4442_test.js b/jscomp/test/dist/jscomp/test/gpr_4442_test.js
index d09ea1d07..275b1dfd6 100644
--- a/jscomp/test/dist/jscomp/test/gpr_4442_test.js
+++ b/jscomp/test/dist/jscomp/test/gpr_4442_test.js
@@ -20,7 +20,8 @@ var u = (function fib(n){
     return 1
   }
   return fib(n-1) + fib(n-2)
-});
+}
+);
 
 eq("File \"jscomp/test/gpr_4442_test.ml\", line 14, characters 6-13", u(2), 2);
 
diff --git a/jscomp/test/dist/jscomp/test/polymorphic_raw_test.js b/jscomp/test/dist/jscomp/test/polymorphic_raw_test.js
index 34cbc4dca..397ff81bd 100644
--- a/jscomp/test/dist/jscomp/test/polymorphic_raw_test.js
+++ b/jscomp/test/dist/jscomp/test/polymorphic_raw_test.js
@@ -28,7 +28,8 @@ function eq(loc, x, y) {
   };
 }
 
-var f = ((a) => typeof a);
+var f = ((a) => typeof a
+);
 
 var a = f(3);
 
diff --git a/jscomp/test/dist/jscomp/test/raw_output_test.js b/jscomp/test/dist/jscomp/test/raw_output_test.js
index 1eff4d43c..be06893a9 100644
--- a/jscomp/test/dist/jscomp/test/raw_output_test.js
+++ b/jscomp/test/dist/jscomp/test/raw_output_test.js
@@ -7,7 +7,8 @@ function mk(fn) {
   return Curry._1(fn, undefined);
 }
 
-(((_)=> console.log('should works'))(undefined));
+(((_)=> console.log('should works')
+    )(undefined));
 
 console.log((function () {
           return 1;
diff --git a/jscomp/test/dist/jscomp/test/re_or_res/reasonReactOptimizedCreateClass.js b/jscomp/test/dist/jscomp/test/re_or_res/reasonReactOptimizedCreateClass.js
index 8f6a418e3..d3c256654 100644
--- a/jscomp/test/dist/jscomp/test/re_or_res/reasonReactOptimizedCreateClass.js
+++ b/jscomp/test/dist/jscomp/test/re_or_res/reasonReactOptimizedCreateClass.js
@@ -879,7 +879,8 @@ var factory = (function factory(ReactComponent, isValidElement, ReactNoopUpdateQ
   }
 
   return createClass;
-});
+}
+);
 
 var reactNoopUpdateQueue = new React.Component().updater;
 
diff --git a/jscomp/test/dist/jscomp/test/string_interp_test.js b/jscomp/test/dist/jscomp/test/string_interp_test.js
index 597d0fbc3..fe94e2bfb 100644
--- a/jscomp/test/dist/jscomp/test/string_interp_test.js
+++ b/jscomp/test/dist/jscomp/test/string_interp_test.js
@@ -51,9 +51,11 @@ function test5(x) {
   return "" + x;
 }
 
-var js_in_raw = ("hello" + "你好");
+var js_in_raw = ("hello" + "你好"
+);
 
-var j_in_raw = ("hello" + "你好");
+var j_in_raw = ("hello" + "你好"
+);
 
 var b = "test";
 
diff --git a/jscomp/test/dist/jscomp/test/unsafe_ppx_test.js b/jscomp/test/dist/jscomp/test/unsafe_ppx_test.js
index ba00a1294..6fc58eaba 100644
--- a/jscomp/test/dist/jscomp/test/unsafe_ppx_test.js
+++ b/jscomp/test/dist/jscomp/test/unsafe_ppx_test.js
@@ -22,7 +22,8 @@ var regression4 = Math.max;
 function g(a) {
   var regression = (function(x,y){
    return ""
-});
+}
+  );
   var regression2 = Math.max;
   regression(a, Stdlib.failwith);
   Curry._2(regression2, 3, 2);
diff --git a/test/blackbox-tests/melange-ppx-raw.t b/test/blackbox-tests/melange-ppx-raw.t
index cb8b7e67d..7f7868c66 100644
--- a/test/blackbox-tests/melange-ppx-raw.t
+++ b/test/blackbox-tests/melange-ppx-raw.t
@@ -31,3 +31,24 @@ Adding a callback breaks
                             ^^^^^^^^^^^^^^^^^^^^^^
   Error: `%mel.raw' can only be applied to a string
   [1]
+
+Show expressions in `%mel.raw` get wrapped in parentheses with proper syntax
+
+  $ cat > main.ml <<EOF
+  > let () = [%mel.raw {|
+  > // before
+  > f(1,2)
+  > // after
+  > |}]
+  > EOF
+  $ melc -ppx melppx main.ml
+  // Generated by Melange
+  'use strict';
+  
+  
+  ((// before
+  f(1,2)
+  // after
+    ));
+  
+  /*  Not a pure module */