diff --git a/examples/x64/hello_world.v b/examples/x64/hello_world.v
index 6ebcf145e6..8c538cf58b 100644
--- a/examples/x64/hello_world.v
+++ b/examples/x64/hello_world.v
@@ -1,14 +1,21 @@
-fn test_fn() {
-	println('test fn')
-}
+fn println(s string) { }
+
+//fn test_fn() {
+	//println('test fn')
+//}
 
 fn main() {
 	println('x64 test')
-	for _ in 0..5 {
+	//i := 0
+	//for i < 5 {
+	for _ in 1..5 {
 		println('Hello world from V x64 machine code generator!')
+		//i++
 	}
+		/*
 	println('Hello again!')
 	//test_fn()
 	println('done')
+	*/
 }
 
diff --git a/vlib/compiler/main.v b/vlib/compiler/main.v
index c6fc52dfaf..eeb6af078b 100644
--- a/vlib/compiler/main.v
+++ b/vlib/compiler/main.v
@@ -420,7 +420,7 @@ pub fn (v mut V) compile_x64() {
 		println('v -x64 can only generate Linux binaries for now')
 		println('You are not on a Linux system, so you will not ' + 'be able to run the resulting executable')
 	}
-	v.files << v.v_files_from_dir(filepath.join(v.pref.vlib_path,'builtin','bare'))
+	//v.files << v.v_files_from_dir(filepath.join(v.pref.vlib_path,'builtin','bare'))
 	v.files << v.dir
 
 	table := &table.Table{}
diff --git a/vlib/compiler/x64/elf.v b/vlib/compiler/x64/elf.v
deleted file mode 100644
index ff018cb784..0000000000
--- a/vlib/compiler/x64/elf.v
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
-// Use of this source code is governed by an MIT license
-// that can be found in the LICENSE file.
-module x64
-
-import os
-
-const (
-	mag0 = 0x7f
-	mag1 = `E`
-	mag2 = `L`
-	mag3 = `F`
-	ei_class = 4
-	elfclass64 = 2
-	elfdata2lsb = 1
-	ev_current = 1
-	elf_osabi = 0
-	// ELF file types
-	et_rel = 1
-	et_exec = 2
-	et_dyn = 3
-	e_machine = 0x3e
-	shn_xindex = 0xffff
-	sht_null = 0
-)
-
-const (
-	segment_start = 0x400000
-)
-
-pub fn (g mut Gen) generate_elf_header() {
-	g.buf << [byte(mag0), mag1, mag2, mag3]
-	g.buf << elfclass64 // file class
-	g.buf << elfdata2lsb // data encoding
-	g.buf << ev_current // file version
-	g.buf << 1 // elf_osabi
-	g.write64(0) // et_rel) // et_rel for .o
-	g.write16(2) // e_type
-	g.write16(e_machine) //
-	g.write32(ev_current) // e_version
-	eh_size := 0x40
-	phent_size := 0x38
-	g.write64(segment_start + eh_size + phent_size) // e_entry
-	g.write64(0x40) // e_phoff
-	g.write64(0) // e_shoff
-	g.write32(0) // e_flags
-	g.write16(eh_size) // e_ehsize
-	g.write16(phent_size) // e_phentsize
-	g.write16(1) // e_phnum
-	g.write16(0) // e_shentsize
-	g.write16(0) // e_shnum (number of sections)
-	g.write16(0) // e_shstrndx
-	// Elf64_Phdr
-	g.write32(1) // p_type
-	g.write32(5) // p_flags
-	g.write64(0) // p_offset
-	g.write64(segment_start) // p_vaddr addr:050
-	g.write64(segment_start) //
-	g.file_size_pos = g.buf.len
-	g.write64(0) // p_filesz PLACEHOLDER, set to file_size later // addr: 060
-	g.write64(0) // p_memsz
-	g.write64(0x1000) // p_align
-	// user code starts here at
-	// address: 00070 and a half
-	g.code_start_pos = g.buf.len
-	g.call(0) // call main function, it's not guaranteed to be the first
-}
-
-pub fn (g mut Gen) generate_elf_footer() {
-	// Return 0
-	g.mov(.edi, 0) // ret value
-	g.mov(.eax, 60)
-	g.syscall()
-	// Strings table
-	// Loop thru all strings and set the right addresses
-	for i, s in g.strings {
-		g.write64_at(segment_start + g.buf.len, int(g.str_pos[i]))
-		g.write_string(s)
-		g.write8(6)
-	}
-	// Now we know the file size, set it
-	file_size := g.buf.len
-	g.write64_at(file_size, g.file_size_pos) // set file size 64 bit value
-	g.write64_at(file_size, g.file_size_pos + 8)
-	// call main function, it's not guaranteed to be the first
-	// we generated call(0) ("e8 0")
-	// no need to replace "0" with a relative address of the main function
-	// +1 is for "e8"
-	// -5 is for "e8 00 00 00 00"
-	g.write64_at(int(g.main_fn_addr - g.code_start_pos) - 5, g.code_start_pos + 1)
-	// Create the binary
-	mut f := os.create(g.out_name)or{
-		panic(err)
-	}
-	os.chmod(g.out_name, 0775)
-	f.write_bytes(g.buf.data, g.buf.len)
-	f.close()
-	println('x64 elf binary has been successfully generated')
-}
-
diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index c71065c82b..87a4b0cc9d 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -8,10 +8,10 @@ import (
 	v.types
 )
 
-pub type Expr = BinaryExpr | UnaryExpr | IfExpr | StringLiteral | IntegerLiteral |
+pub type Expr = BinaryExpr | UnaryExpr | IfExpr | StringLiteral | IntegerLiteral | 	
 FloatLiteral | Ident | CallExpr | BoolLiteral | StructInit | ArrayInit
 
-pub type Stmt = VarDecl | FnDecl | Return | Module | Import | ExprStmt | AssignStmt |
+pub type Stmt = VarDecl | FnDecl | Return | Module | Import | ExprStmt | AssignStmt | 	
 ForStmt | StructDecl
 // Stand-alone expression in a statement list.
 pub struct ExprStmt {
@@ -158,9 +158,9 @@ pub:
 
 pub struct IfExpr {
 pub:
-	tok_kind token.Kind
-	cond     Expr
-	stmts    []Stmt
+	tok_kind   token.Kind
+	cond       Expr
+	stmts      []Stmt
 	else_stmts []Stmt
 }
 
@@ -168,6 +168,7 @@ pub struct ForStmt {
 pub:
 	cond  Expr
 	stmts []Stmt
+	is_in bool
 }
 
 pub struct ReturnStmt {
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 5a8964d078..aa91deed2d 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -72,7 +72,11 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 		}
 		ast.ForStmt {
 			g.write('while (')
-			g.expr(it.cond)
+			if !it.is_in {
+				// `for in` loops don't have a condition
+				println('it cond')
+				g.expr(it.cond)
+			}
 			g.writeln(') {')
 			for stmt in it.stmts {
 				g.stmt(stmt)
@@ -116,7 +120,8 @@ fn (g mut Gen) expr(node ast.Expr) {
 			if it.op in [.inc, .dec] {
 				g.expr(it.left)
 				g.write(it.op.str())
-			} else {
+			}
+			else {
 				g.write(it.op.str())
 				g.expr(it.left)
 			}
diff --git a/vlib/v/gen/x64/elf.v b/vlib/v/gen/x64/elf.v
index ff018cb784..1fc4be2752 100644
--- a/vlib/v/gen/x64/elf.v
+++ b/vlib/v/gen/x64/elf.v
@@ -89,12 +89,11 @@ pub fn (g mut Gen) generate_elf_footer() {
 	// -5 is for "e8 00 00 00 00"
 	g.write64_at(int(g.main_fn_addr - g.code_start_pos) - 5, g.code_start_pos + 1)
 	// Create the binary
-	mut f := os.create(g.out_name)or{
+	mut f := os.create(g.out_name) or {
 		panic(err)
 	}
-	os.chmod(g.out_name, 0775)
+	os.chmod(g.out_name, 0775) // make it an executable
 	f.write_bytes(g.buf.data, g.buf.len)
 	f.close()
 	println('x64 elf binary has been successfully generated')
 }
-
diff --git a/vlib/v/gen/x64/gen.v b/vlib/v/gen/x64/gen.v
index 0ccf602e38..fa4280c29e 100644
--- a/vlib/v/gen/x64/gen.v
+++ b/vlib/v/gen/x64/gen.v
@@ -43,7 +43,6 @@ enum Size {
 
 pub fn gen(files []ast.File, out_name string) {
 	mut g := Gen{
-		// out: strings.new_builder(100)
 		sect_header_name_pos: 0
 		buf: []
 		out_name: out_name
@@ -58,6 +57,7 @@ pub fn gen(files []ast.File, out_name string) {
 	g.generate_elf_footer()
 }
 
+/*
 pub fn new_gen(out_name string) &Gen {
 	return &Gen{
 		sect_header_name_pos: 0
@@ -65,6 +65,8 @@ pub fn new_gen(out_name string) &Gen {
 		out_name: out_name
 	}
 }
+*/
+
 
 pub fn (g &Gen) pos() i64 {
 	return g.buf.len
@@ -233,6 +235,15 @@ pub fn (g mut Gen) save_main_fn_addr() {
 	g.main_fn_addr = g.buf.len
 }
 
+pub fn (g mut Gen) gen_print_from_expr(expr ast.Expr) {
+	match expr {
+		ast.StringLiteral {
+			g.gen_print(it.val)
+		}
+		else {}
+	}
+}
+
 pub fn (g mut Gen) gen_print(s string) {
 	g.strings << s + '\n'
 	// g.string_addr[s] = str_pos
@@ -306,23 +317,19 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 			g.writeln(';')
 		}
 		ast.FnDecl {
-			if it.name == 'main' {
-				g.write('int ${it.name}(')
+			is_main := it.name == 'main'
+			if is_main {
+				g.save_main_fn_addr()
 			}
-			else {
-				g.write('$it.typ.name ${it.name}(')
-			}
-			for arg in it.args {
-				g.write(arg.typ.name + ' ' + arg.name)
-			}
-			g.writeln(') { ')
+			for arg in it.args {}
 			for stmt in it.stmts {
 				g.stmt(stmt)
 			}
-			if it.name == 'main' {
-				g.writeln('return 0;')
+			if is_main {
+				println('end of main: gen exit')
+				g.gen_exit()
 			}
-			g.writeln('}')
+			g.ret()
 		}
 		ast.Return {
 			g.write('return ')
@@ -335,6 +342,7 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 			g.writeln(';')
 		}
 		ast.ForStmt {
+			if it.is_in {}
 			g.write('while (')
 			g.expr(it.cond)
 			g.writeln(') {')
@@ -401,6 +409,11 @@ fn (g mut Gen) expr(node ast.Expr) {
 			g.write('}')
 		}
 		ast.CallExpr {
+			if it.name == 'println' || it.name == 'print' {
+				expr := it.args[0]
+				g.gen_print_from_expr(expr)
+			}
+			/*
 			g.write('${it.name}(')
 			for i, expr in it.args {
 				g.expr(expr)
@@ -409,6 +422,8 @@ fn (g mut Gen) expr(node ast.Expr) {
 				}
 			}
 			g.write(')')
+			*/
+
 		}
 		ast.ArrayInit {
 			g.writeln('new_array_from_c_array($it.exprs.len, $it.exprs.len, sizeof($it.typ.name), {\t')
diff --git a/vlib/v/parser/parser.v b/vlib/v/parser/parser.v
index 9a429c1419..297916406a 100644
--- a/vlib/v/parser/parser.v
+++ b/vlib/v/parser/parser.v
@@ -93,6 +93,7 @@ pub fn parse_file(path string, table &table.Table) ast.File {
 pub fn parse_files(paths []string, table &table.Table) []ast.File {
 	mut files := []ast.File
 	for path in paths {
+		println('parse file "$path"')
 		mut stmts := []ast.Stmt
 		text := os.read_file(path) or {
 			panic(err)
@@ -437,6 +438,24 @@ pub fn (p mut Parser) expr(rbp int) (ast.Expr,types.Type) {
 
 fn (p mut Parser) for_statement() ast.ForStmt {
 	p.check(.key_for)
+	// `for i in start .. end`
+	if p.peek_tok.kind == .key_in {
+		var := p.check_name()
+		p.check(.key_in)
+		start := p.tok.lit.int()
+		p.check(.number)
+		p.check(.dotdot)
+		end := p.tok.lit.int()
+		// println('for start=$start $end')
+		p.check(.number)
+		stmts := p.parse_block()
+		// println('nr stmts=$stmts.len')
+		return ast.ForStmt{
+			stmts: stmts
+			is_in: true
+		}
+	}
+	// `for cond {`
 	cond,typ := p.expr(0)
 	if !types.check(types.bool_type, typ) {
 		p.error('non-bool used as for condition')