diff --git a/vlib/builtin/js/array_test.js.v b/vlib/builtin/js/array_test.js.v
index b90a8073dc..49e2d6f220 100644
--- a/vlib/builtin/js/array_test.js.v
+++ b/vlib/builtin/js/array_test.js.v
@@ -1331,8 +1331,8 @@ fn test_struct_array_of_multi_type_in() {
 		},
 	]
 	println(ivan in people)
-	println('TODO: Map eq')
-	// assert ivan in people
+	// println('TODO: Map eq')
+	assert ivan in people
 }
 
 fn test_struct_array_of_multi_type_index() {
diff --git a/vlib/builtin/js/map.js.v b/vlib/builtin/js/map.js.v
index 033a5fde9e..1b913674b6 100644
--- a/vlib/builtin/js/map.js.v
+++ b/vlib/builtin/js/map.js.v
@@ -1,7 +1,8 @@
 module builtin
 
 struct map {
-	m   JS.Map
+	m JS.Map
+pub:
 	len int
 }
 
@@ -14,7 +15,7 @@ pub fn (mut m map) delete(key voidptr) {
 pub fn (m &map) free() {}
 
 #map.prototype[Symbol.iterator] = function () { return this.map[Symbol.iterator](); }
-
+//#Object.defineProperty(map.prototype,"len",{get: function() { return this.map.size; }})
 #map.prototype.toString = function () {
 #function fmtKey(key) { return typeof key == 'string' ? '\'' + key + '\'' : key}
 #let res = '{'
diff --git a/vlib/rand/rand.c.v b/vlib/rand/rand.c.v
index 066d8ebc2b..cfd91b411f 100644
--- a/vlib/rand/rand.c.v
+++ b/vlib/rand/rand.c.v
@@ -125,3 +125,16 @@ pub fn hex(len int) string {
 pub fn ascii(len int) string {
 	return string_from_set(ascii_chars, len)
 }
+
+fn deinit() {
+	unsafe {
+		default_rng.free() // free the implementation
+		free(default_rng) // free the interface wrapper itself
+	}
+}
+
+// init initializes the default RNG.
+fn init() {
+	default_rng = new_default()
+	C.atexit(deinit)
+}
diff --git a/vlib/rand/rand.js.v b/vlib/rand/rand.js.v
new file mode 100644
index 0000000000..ce4ea265c2
--- /dev/null
+++ b/vlib/rand/rand.js.v
@@ -0,0 +1,17 @@
+module rand
+
+// init initializes the default RNG.
+fn init() {
+	default_rng = new_default()
+}
+
+pub fn string(len int) string {
+	result := ''
+	#
+	#const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
+	#const charactersLength = characters.length;
+	#for (let i = 0;i < len.val;i++)
+	#result.str += characters.charAt(Math.random() * charactersLength);
+
+	return result
+}
diff --git a/vlib/rand/rand.v b/vlib/rand/rand.v
index 29b813649e..cac98b8c74 100644
--- a/vlib/rand/rand.v
+++ b/vlib/rand/rand.v
@@ -38,19 +38,6 @@ __global (
 	default_rng &PRNG
 )
 
-// init initializes the default RNG.
-fn init() {
-	default_rng = new_default()
-	C.atexit(deinit)
-}
-
-fn deinit() {
-	unsafe {
-		default_rng.free() // free the implementation
-		free(default_rng) // free the interface wrapper itself
-	}
-}
-
 // new_default returns a new instance of the default RNG. If the seed is not provided, the current time will be used to seed the instance.
 [manualfree]
 pub fn new_default(config config.PRNGConfigStruct) &PRNG {
diff --git a/vlib/rand/rand_test.js.v b/vlib/rand/rand_test.js.v
new file mode 100644
index 0000000000..8603bbd4a5
--- /dev/null
+++ b/vlib/rand/rand_test.js.v
@@ -0,0 +1,7 @@
+import rand
+
+fn test_string() {
+	res := rand.string(4)
+	assert res.len == 4
+	println(res)
+}
diff --git a/vlib/rand/wyrand/wyrand.js.v b/vlib/rand/wyrand/wyrand.js.v
new file mode 100644
index 0000000000..1e5d4b4424
--- /dev/null
+++ b/vlib/rand/wyrand/wyrand.js.v
@@ -0,0 +1,3 @@
+module wyrand
+
+pub fn (mut r WyRandRNG) free() {}
diff --git a/vlib/rand/wyrand/wyrand.v b/vlib/rand/wyrand/wyrand.v
index a55a243ce1..22b71afbad 100644
--- a/vlib/rand/wyrand/wyrand.v
+++ b/vlib/rand/wyrand/wyrand.v
@@ -250,9 +250,3 @@ pub fn (mut rng WyRandRNG) f64_in_range(min f64, max f64) f64 {
 	}
 	return min + rng.f64n(max - min)
 }
-
-// free should be called when the generator is no longer needed
-[unsafe]
-pub fn (mut rng WyRandRNG) free() {
-	unsafe { free(rng) }
-}
diff --git a/vlib/rand/wyrand/z_wyrand.c.v b/vlib/rand/wyrand/z_wyrand.c.v
new file mode 100644
index 0000000000..e6cb6b4b45
--- /dev/null
+++ b/vlib/rand/wyrand/z_wyrand.c.v
@@ -0,0 +1,7 @@
+module wyrand
+
+// free should be called when the generator is no longer needed
+[unsafe]
+pub fn (mut rng WyRandRNG) free() {
+	unsafe { free(rng) }
+}
diff --git a/vlib/v/gen/js/auto_str_methods.v b/vlib/v/gen/js/auto_str_methods.v
index 2c7cedccc6..38b109aa57 100644
--- a/vlib/v/gen/js/auto_str_methods.v
+++ b/vlib/v/gen/js/auto_str_methods.v
@@ -589,9 +589,9 @@ fn (mut g JsGen) gen_str_for_map(info ast.Map, styp string, str_fn_name string)
 	g.definitions.writeln('\tstrings__Builder_write_string(sb, new string("{"));')
 	g.definitions.writeln('\tlet i = 0;')
 	g.definitions.writeln('\tfor (let [key,value] of m.map) {')
-
+	g.definitions.writeln('\t\tkey = new ${key_styp}(key);')
 	if key_sym.kind == .string {
-		g.definitions.writeln('\t\tstrings__Builder_write_string(sb, new string(key));')
+		g.definitions.writeln('\t\tstrings__Builder_write_string(sb, new string("\'" + key.str + "\'"));')
 	} else if key_sym.kind == .rune {
 		// tmp_str := str_intp_rune('${key_str_fn_name}(key)')
 		// g.definitions.writeln('\t\tstrings__Builder_write_string(sb, $tmp_str);')
diff --git a/vlib/v/gen/js/builtin_types.v b/vlib/v/gen/js/builtin_types.v
index 4e0e8d6f39..7dd4476574 100644
--- a/vlib/v/gen/js/builtin_types.v
+++ b/vlib/v/gen/js/builtin_types.v
@@ -300,11 +300,6 @@ fn (mut g JsGen) gen_builtin_prototype(c BuiltinPrototypeConfig) {
 	g.dec_indent()
 	g.writeln('};\n')
 	g.writeln('function ${c.typ_name}__eq(self,other) { return $c.eq; } ')
-	for method in g.method_fn_decls[c.typ_name] {
-		g.inside_def_typ_decl = true
-		g.gen_method_decl(method, .struct_method)
-		g.inside_def_typ_decl = false
-	}
 }
 
 // generate builtin type definitions, used for casting and methods.
diff --git a/vlib/v/gen/js/infix.v b/vlib/v/gen/js/infix.v
index 010c89ca9d..767ce56a72 100644
--- a/vlib/v/gen/js/infix.v
+++ b/vlib/v/gen/js/infix.v
@@ -294,11 +294,13 @@ fn (mut g JsGen) infix_in_not_in_op(node ast.InfixExpr) {
 		g.gen_deref_ptr(node.right_type)
 		g.write('.map.has(')
 		g.expr(node.left)
+		/*
 		if l_sym.sym.kind == .string {
 			g.write('.str')
 		} else {
 			g.write('.valueOf()')
-		}
+		}*/
+		g.write('.\$toJS()')
 		g.write(')')
 	} else {
 		g.write('.str.includes(')
diff --git a/vlib/v/gen/js/js.v b/vlib/v/gen/js/js.v
index ac1cb511fc..be0f8cf132 100644
--- a/vlib/v/gen/js/js.v
+++ b/vlib/v/gen/js/js.v
@@ -200,6 +200,18 @@ pub fn gen(files []&ast.File, table &ast.Table, pref &pref.Preferences) string {
 			}
 		}
 	}
+
+	for mod_name in g.table.modules {
+		g.writeln('// Initializations for module $mod_name')
+		init_fn_name := '${mod_name}.init'
+		if initfn := g.table.find_fn(init_fn_name) {
+			if initfn.return_type == ast.void_type && initfn.params.len == 0 {
+				mod_c_name := util.no_dots(mod_name)
+				init_fn_c_name := '${mod_c_name}__init'
+				g.writeln('${init_fn_c_name}();')
+			}
+		}
+	}
 	g.write('js_main();')
 	g.escape_namespace()
 	// resolve imports
@@ -207,6 +219,7 @@ pub fn gen(files []&ast.File, table &ast.Table, pref &pref.Preferences) string {
 	nodes := deps_resolved.nodes
 
 	mut out := g.definitions.str() + g.hashes()
+
 	// equality check for js objects
 	// TODO: Fix msvc bug that's preventing $embed_file('fast_deep_equal.js')
 	// unsafe {
@@ -221,8 +234,8 @@ pub fn gen(files []&ast.File, table &ast.Table, pref &pref.Preferences) string {
 		out += 'if (typeof module === "object" && module.exports) module.exports = $export;\n'
 	}
 	out += '\n'
-	out += g.out.str()
 
+	out += g.out.str()
 	/*
 	TODO(playX): Again add support for these doc comments
 	for node in nodes {
@@ -876,12 +889,18 @@ fn (mut g JsGen) expr(node ast.Expr) {
 			g.write(')')
 		}
 		ast.PostfixExpr {
+			// match node.expr {
+			//	ast.IndexExpr {
+			//		g.gen_postfix_index_expr(node.expr,node.op)
+			//		} else {
 			g.expr(node.expr)
 			if node.op in [.inc, .dec] {
 				g.write('.val $node.op')
 			} else {
 				g.write(node.op.str())
 			}
+			//		}
+			//	}
 		}
 		ast.PrefixExpr {
 			if node.op in [.amp, .mul] {
@@ -1126,6 +1145,7 @@ fn (mut g JsGen) gen_assign_stmt(stmt ast.AssignStmt, semicolon bool) {
 				}
 			}
 			mut array_set := false
+			mut map_set := false
 			match left {
 				ast.IndexExpr {
 					g.expr(left.left)
@@ -1133,17 +1153,24 @@ fn (mut g JsGen) gen_assign_stmt(stmt ast.AssignStmt, semicolon bool) {
 						g.write('.valueOf()')
 					}
 					array_set = true
+
 					if g.table.get_type_symbol(left.left_type).kind == .map {
 						g.write('.map.set(')
+						map_set = true
 					} else {
 						g.write('.arr.set(')
 					}
-					g.write('new int(')
-					g.cast_stack << ast.int_type_idx
-					g.expr(left.index)
-					g.write('.valueOf()')
-					g.cast_stack.delete_last()
-					g.write('),')
+					if map_set {
+						g.expr(left.index)
+						g.write('.\$toJS(),')
+					} else {
+						g.write('new int(')
+						g.cast_stack << ast.int_type_idx
+						g.expr(left.index)
+						g.write('.valueOf()')
+						g.cast_stack.delete_last()
+						g.write('),')
+					}
 				}
 				else {
 					g.expr(left)
@@ -2308,6 +2335,7 @@ fn (mut g JsGen) gen_index_expr(expr ast.IndexExpr) {
 		g.write(')')
 	} else if left_typ.kind == .map {
 		g.expr(expr.left)
+
 		if expr.is_setter {
 			g.inside_map_set = true
 			g.write('.map.set(')
@@ -2315,7 +2343,7 @@ fn (mut g JsGen) gen_index_expr(expr ast.IndexExpr) {
 			g.write('.map.get(')
 		}
 		g.expr(expr.index)
-		g.write('.toString()')
+		g.write('.\$toJS()')
 		if !expr.is_setter {
 			g.write(')')
 		}
@@ -2632,6 +2660,7 @@ fn (mut g JsGen) gen_map_init_expr(it ast.MapInit) {
 			val := it.vals[i]
 			g.write('[')
 			g.expr(key)
+			g.write('.\$toJS()')
 			g.write(', ')
 			g.expr(val)
 			g.write(']')
@@ -2950,3 +2979,95 @@ fn replace_op(s string) string {
 		else { '' }
 	}
 }
+
+fn (mut g JsGen) gen_postfix_index_expr(expr ast.IndexExpr, op token.Kind) {
+	left_typ := g.table.get_type_symbol(expr.left_type)
+	// TODO: Handle splice setting if it's implemented
+	if expr.index is ast.RangeExpr {
+		if left_typ.kind == .array {
+			g.write('array_slice(')
+		} else {
+			g.write('string_slice(')
+		}
+		g.expr(expr.left)
+		if expr.left_type.is_ptr() {
+			g.write('.valueOf()')
+		}
+		g.write(',')
+
+		if expr.index.has_low {
+			g.expr(expr.index.low)
+		} else {
+			g.write('new int(0)')
+		}
+		g.write(', ')
+		if expr.index.has_high {
+			g.expr(expr.index.high)
+		} else {
+			g.expr(expr.left)
+			if expr.left_type.is_ptr() {
+				g.write('.valueOf()')
+			}
+			g.write('.len')
+		}
+		g.write(')')
+	} else if left_typ.kind == .map {
+		g.expr(expr.left)
+
+		if expr.is_setter {
+			g.inside_map_set = true
+			g.write('.map.set(')
+		} else {
+			g.write('.map.get(')
+		}
+		g.expr(expr.index)
+		g.write('.\$toJS()')
+		if !expr.is_setter {
+			g.write(')')
+		} else {
+			g.write(',')
+			lsym := g.table.get_type_symbol(expr.left_type)
+			key_typ := match lsym.info {
+				ast.Map {
+					lsym.info.value_type
+				}
+				else {
+					verror('unreachable')
+				}
+			}
+			g.write('new ${g.typ(key_typ)}(')
+
+			g.expr(expr.left)
+			g.write('.map.get(')
+			g.expr(expr.index)
+			g.write('.\$toJS())')
+			match op {
+				.inc {
+					g.write('.val + 1)')
+				}
+				.dec {
+					g.write('.val - 1)')
+				}
+				else {
+					verror('not yet implemented')
+				}
+			}
+			g.write(')')
+		}
+	} else if left_typ.kind == .string {
+		if expr.is_setter {
+			// TODO: What's the best way to do this?
+			// 'string'[3] = `o`
+		} else {
+			// TODO: Maybe use u16 there? JS String returns values up to 2^16-1
+			g.write('new byte(')
+			g.expr(expr.left)
+			if expr.left_type.is_ptr() {
+				g.write('.valueOf()')
+			}
+			g.write('.str.charCodeAt(')
+			g.expr(expr.index)
+			g.write('))')
+		}
+	}
+}