diff --git a/vlib/v/checker/check_types.v b/vlib/v/checker/check_types.v
index 95100b2280..3605810568 100644
--- a/vlib/v/checker/check_types.v
+++ b/vlib/v/checker/check_types.v
@@ -305,10 +305,11 @@ pub fn (c &Checker) get_default_fmt(ftyp, typ table.Type) byte {
 	} else if typ.is_pointer() {
 		return `p`
 	} else {
-		sym := c.table.get_type_symbol(ftyp)
+		mut sym := c.table.get_type_symbol(ftyp)
 		if sym.kind == .alias {
 			// string aliases should be printable
 			info := sym.info as table.Alias
+			sym = c.table.get_type_symbol(info.parent_type)
 			if info.parent_type == table.string_type {
 				return `s`
 			}
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index f88327a292..8ccf1a4f43 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -562,8 +562,8 @@ pub fn (mut c Checker) infix_expr(mut infix_expr ast.InfixExpr) table.Type {
 	right_type := c.expr(infix_expr.right)
 	// right_type = c.unwrap_genric(c.expr(infix_expr.right))
 	infix_expr.right_type = right_type
-	right := c.table.get_type_symbol(right_type)
-	left := c.table.get_type_symbol(left_type)
+	mut right := c.table.get_type_symbol(right_type)
+	mut left := c.table.get_type_symbol(left_type)
 	left_default := c.table.get_type_symbol(c.table.mktyp(left_type))
 	left_pos := infix_expr.left.position()
 	right_pos := infix_expr.right.position()
@@ -610,21 +610,47 @@ pub fn (mut c Checker) infix_expr(mut infix_expr ast.InfixExpr) table.Type {
 			return table.bool_type
 		}
 		.plus, .minus, .mul, .div, .mod, .xor, .amp, .pipe { // binary operators that expect matching types
+			if right.info is table.Alias &&
+				(right.info as table.Alias).language != .c && c.mod == c.table.type_to_str(right_type).split('.')[0] {
+				right = c.table.get_type_symbol((right.info as table.Alias).parent_type)
+			}
+			if left.info is table.Alias &&
+				(left.info as table.Alias).language != .c && c.mod == c.table.type_to_str(left_type).split('.')[0] {
+				left = c.table.get_type_symbol((left.info as table.Alias).parent_type)
+			}
 			if left.kind in [.array, .array_fixed, .map, .struct_] {
 				if left.has_method(infix_expr.op.str()) {
-					return_type = left_type
+					if method := left.find_method(infix_expr.op.str()) {
+						return_type = method.return_type
+					} else {
+						return_type = left_type
+					}
 				} else {
 					left_name := c.table.type_to_str(left_type)
 					right_name := c.table.type_to_str(right_type)
-					c.error('mismatched types `$left_name` and `$right_name`', left_pos)
+					if left_name == right_name {
+						c.error('operation `$left_name` $infix_expr.op.str() `$right_name` does not exist, please define it',
+							left_pos)
+					} else {
+						c.error('mismatched types `$left_name` and `$right_name`', left_pos)
+					}
 				}
 			} else if right.kind in [.array, .array_fixed, .map, .struct_] {
 				if right.has_method(infix_expr.op.str()) {
-					return_type = right_type
+					if method := right.find_method(infix_expr.op.str()) {
+						return_type = method.return_type
+					} else {
+						return_type = right_type
+					}
 				} else {
 					left_name := c.table.type_to_str(left_type)
 					right_name := c.table.type_to_str(right_type)
-					c.error('mismatched types `$left_name` and `$right_name`', right_pos)
+					if left_name == right_name {
+						c.error('operation `$left_name` $infix_expr.op.str() `$right_name` does not exist, please define it',
+							right_pos)
+					} else {
+						c.error('mismatched types `$left_name` and `$right_name`', right_pos)
+					}
 				}
 			} else {
 				promoted_type := c.promote(c.table.unalias_num_type(left_type), c.table.unalias_num_type(right_type))
diff --git a/vlib/v/checker/tests/.gitignore b/vlib/v/checker/tests/.gitignore
index 07d7f52ac5..868d19e77b 100644
--- a/vlib/v/checker/tests/.gitignore
+++ b/vlib/v/checker/tests/.gitignore
@@ -1,3 +1,4 @@
 *.v
 *.c
-!*_test.v
\ No newline at end of file
+!*_test.v
+!modules/**/*.v
\ No newline at end of file
diff --git a/vlib/v/checker/tests/modules/overload_return_type.out b/vlib/v/checker/tests/modules/overload_return_type.out
new file mode 100644
index 0000000000..de1dc3e0c9
--- /dev/null
+++ b/vlib/v/checker/tests/modules/overload_return_type.out
@@ -0,0 +1,6 @@
+vlib/v/checker/tests/modules/overload_return_type/main.v:8:11: error: cannot assign `int` to `two` of type `Point`
+    6 |     one := Point {x:1, y:2}
+    7 |     mut two := Point {x:5, y:1}
+    8 |     two = one + two
+      |           ~~~~~~~~~
+    9 | }
diff --git a/vlib/v/checker/tests/modules/overload_return_type/main.v b/vlib/v/checker/tests/modules/overload_return_type/main.v
new file mode 100644
index 0000000000..fe27e3ee3f
--- /dev/null
+++ b/vlib/v/checker/tests/modules/overload_return_type/main.v
@@ -0,0 +1,9 @@
+module main
+
+import point { Point }
+
+fn main() {
+    one := Point {x:1, y:2}
+    mut two := Point {x:5, y:1}
+    two = one + two
+}
diff --git a/vlib/v/checker/tests/modules/overload_return_type/point.v b/vlib/v/checker/tests/modules/overload_return_type/point.v
new file mode 100644
index 0000000000..5f6da09637
--- /dev/null
+++ b/vlib/v/checker/tests/modules/overload_return_type/point.v
@@ -0,0 +1,11 @@
+module point
+
+pub struct Point {
+    mut:
+        x int
+        y int
+}
+
+pub fn (a Point) +(b Point) int {
+    return a.x + b.x
+}
diff --git a/vlib/v/checker/tests/overload_return_type.out b/vlib/v/checker/tests/overload_return_type.out
new file mode 100644
index 0000000000..b15bd4967e
--- /dev/null
+++ b/vlib/v/checker/tests/overload_return_type.out
@@ -0,0 +1,6 @@
+vlib/v/checker/tests/overload_return_type.vv:14:11: error: cannot assign `int` to `two` of type `Point`
+   12 |     mut one := Point {x:1, y:2}
+   13 |     mut two := Point {x:5, y:1}
+   14 |     two = one + two
+      |           ~~~~~~~~~
+   15 | }
diff --git a/vlib/v/checker/tests/overload_return_type.vv b/vlib/v/checker/tests/overload_return_type.vv
new file mode 100644
index 0000000000..f9ae2f11dd
--- /dev/null
+++ b/vlib/v/checker/tests/overload_return_type.vv
@@ -0,0 +1,15 @@
+struct Point {
+    mut:
+        x int
+        y int
+}
+
+fn (a Point) +(b Point) int {
+    return a.x + b.x
+}
+
+fn main() {
+    mut one := Point {x:1, y:2}
+    mut two := Point {x:5, y:1}
+    two = one + two
+}
diff --git a/vlib/v/compiler_errors_test.v b/vlib/v/compiler_errors_test.v
index 893929045a..7c5bea9eaf 100644
--- a/vlib/v/compiler_errors_test.v
+++ b/vlib/v/compiler_errors_test.v
@@ -23,6 +23,7 @@ struct TaskDescription {
 mut:
 	is_error         bool
 	is_skipped       bool
+	is_module bool
 	expected         string
 	found___         string
 	took             time.Duration
@@ -33,25 +34,28 @@ fn test_all() {
 	vroot := os.dir(vexe)
 	os.chdir(vroot)
 	classic_dir := 'vlib/v/checker/tests'
-	classic_tests := get_tests_in_dir(classic_dir)
+	classic_tests := get_tests_in_dir(classic_dir, false)
 	global_dir := '$classic_dir/globals'
-	global_tests := get_tests_in_dir(global_dir)
+	global_tests := get_tests_in_dir(global_dir, false)
+	module_dir := '$classic_dir/modules'
+	module_tests := get_tests_in_dir(module_dir, true)	
 	run_dir := '$classic_dir/run'
-	run_tests := get_tests_in_dir(run_dir)
+	run_tests := get_tests_in_dir(run_dir, false)
 	parser_dir := 'vlib/v/parser/tests'
-	parser_tests := get_tests_in_dir(parser_dir)
+	parser_tests := get_tests_in_dir(parser_dir, false)
 	// -prod so that warns are errors
 	mut tasks := []TaskDescription{}
-	tasks << new_tasks(vexe, classic_dir, '-prod', '.out', classic_tests)
-	tasks << new_tasks(vexe, global_dir, '--enable-globals', '.out', global_tests)
+	tasks << new_tasks(vexe, classic_dir, '-prod', '.out', classic_tests, false)
+	tasks << new_tasks(vexe, global_dir, '--enable-globals', '.out', global_tests, false)
 	tasks <<
-		new_tasks(vexe, classic_dir, '--enable-globals run', '.run.out', ['globals_error.vv'])
-	tasks << new_tasks(vexe, run_dir, 'run', '.run.out', run_tests)
-	tasks << new_tasks(vexe, parser_dir, '-prod', '.out', parser_tests)
+		new_tasks(vexe, classic_dir, '--enable-globals run', '.run.out', ['globals_error.vv'], false)
+	tasks << new_tasks(vexe, module_dir, '-prod run', '.out', module_tests, true)
+	tasks << new_tasks(vexe, run_dir, 'run', '.run.out', run_tests, false)
+	tasks << new_tasks(vexe, parser_dir, '-prod', '.out', parser_tests, false)
 	tasks.run()
 }
 
-fn new_tasks(vexe, dir, voptions, result_extension string, tests []string) []TaskDescription {
+fn new_tasks(vexe, dir, voptions, result_extension string, tests []string, is_module bool) []TaskDescription {
 	paths := vtest.filter_vtest_only(tests, {
 		basepath: dir
 	})
@@ -63,6 +67,7 @@ fn new_tasks(vexe, dir, voptions, result_extension string, tests []string) []Tas
 			voptions: voptions
 			result_extension: result_extension
 			path: path
+			is_module: is_module
 		}
 	}
 	return res
@@ -155,6 +160,11 @@ fn (mut task TaskDescription) execute() {
 	}
 	task.expected = clean_line_endings(expected)
 	task.found___ = clean_line_endings(res.output)
+	$if windows {
+		if task.is_module {
+			task.found___ = task.found___.replace_once('\\', '/')
+		}
+	}
 	if task.expected != task.found___ {
 		task.is_error = true
 	}
@@ -178,11 +188,16 @@ fn diff_content(s1, s2 string) {
 	println('============\n')
 }
 
-fn get_tests_in_dir(dir string) []string {
+fn get_tests_in_dir(dir string, is_module bool) []string {
 	files := os.ls(dir) or {
 		panic(err)
 	}
-	mut tests := files.filter(it.ends_with('.vv'))
+	mut tests := files
+	if !is_module {
+		tests = files.filter(it.ends_with('.vv'))
+	} else {
+		tests = files.filter(!it.ends_with('.out'))
+	}
 	tests.sort()
 	return tests
 }
diff --git a/vlib/v/gen/auto_str_methods.v b/vlib/v/gen/auto_str_methods.v
index b5edd9085f..f8c2215f9a 100644
--- a/vlib/v/gen/auto_str_methods.v
+++ b/vlib/v/gen/auto_str_methods.v
@@ -8,8 +8,12 @@ import v.util
 
 // already generated styp, reuse it
 fn (mut g Gen) gen_str_for_type_with_styp(typ table.Type, styp string) string {
-	sym := g.table.get_type_symbol(typ)
-	str_fn_name := styp_to_str_fn_name(styp)
+	mut sym := g.table.get_type_symbol(typ)
+	mut str_fn_name := styp_to_str_fn_name(styp)
+	if sym.info is table.Alias {
+		sym = g.table.get_type_symbol((sym.info as table.Alias).parent_type)
+		str_fn_name = styp_to_str_fn_name(sym.name.replace('.', '__'))
+	}
 	sym_has_str_method, str_method_expects_ptr, str_nr_args := sym.str_method_info()
 	// generate for type
 	if sym_has_str_method && str_method_expects_ptr && str_nr_args == 1 {
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 7a63cb6ce6..b791f24994 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -2542,9 +2542,16 @@ fn (mut g Gen) infix_expr(node ast.InfixExpr) {
 		a := left_sym.name[0].is_capital() || left_sym.name.contains('.')
 		b := left_sym.kind != .alias
 		c := left_sym.kind == .alias && (left_sym.info as table.Alias).language == .c
-		if node.op in [.plus, .minus, .mul, .div, .mod] && ((a && b) || c) {
+		// Check if aliased type is a struct
+		d := !b &&
+			g.typ((left_sym.info as table.Alias).parent_type).split('__').last()[0].is_capital()
+		if node.op in [.plus, .minus, .mul, .div, .mod] && ((a && b) || c || d) {
 			// Overloaded operators
-			g.write(g.typ(left_type))
+			g.write(g.typ(if !d {
+				left_type
+			} else {
+				(left_sym.info as table.Alias).parent_type
+			}))
 			g.write('_')
 			g.write(util.replace_op(node.op.str()))
 			g.write('(')
@@ -4119,7 +4126,10 @@ fn (g &Gen) sort_structs(typesa []table.TypeSymbol) []table.TypeSymbol {
 }
 
 fn (mut g Gen) gen_expr_to_string(expr ast.Expr, etype table.Type) ?bool {
-	sym := g.table.get_type_symbol(etype)
+	mut sym := g.table.get_type_symbol(etype)
+	if sym.info is table.Alias {
+		sym = g.table.get_type_symbol((sym.info as table.Alias).parent_type)
+	}
 	sym_has_str_method, str_method_expects_ptr, _ := sym.str_method_info()
 	if etype.has_flag(.variadic) {
 		str_fn_name := g.gen_str_for_type(etype)
diff --git a/vlib/v/tests/modules/methods_struct_another_module/methods_struct_test.v b/vlib/v/tests/modules/methods_struct_another_module/methods_struct_test.v
new file mode 100644
index 0000000000..0c17cabdc8
--- /dev/null
+++ b/vlib/v/tests/modules/methods_struct_another_module/methods_struct_test.v
@@ -0,0 +1,16 @@
+module main
+
+import point { Point }
+
+fn test_operator_overloading() {
+    one := Point {x:1, y:2}
+    two := Point {x:5, y:1}
+    sum := one + two
+	assert sum.x == 6
+	assert sum.y == 3
+}
+
+fn test_str_method() {
+    one := Point {x:1, y:2}
+    assert '$one' == '1 2'
+}
\ No newline at end of file
diff --git a/vlib/v/tests/modules/methods_struct_another_module/point.v b/vlib/v/tests/modules/methods_struct_another_module/point.v
new file mode 100644
index 0000000000..5ba3697ba9
--- /dev/null
+++ b/vlib/v/tests/modules/methods_struct_another_module/point.v
@@ -0,0 +1,18 @@
+module point
+
+pub struct Point {
+    pub mut:
+        x int
+        y int
+}
+
+pub fn (a Point) +(b Point) Point {
+    return Point {
+        x: a.x + b.x
+        y: a.y + b.y
+    }
+}
+
+pub fn (a Point) str() string {
+    return '${a.x} ${a.y}'
+}
\ No newline at end of file