diff --git a/.gitignore b/.gitignore
index efbdc99..9d3f7ad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,6 @@
 /bin
 /lib
 /a
-/src/ciabatta.c
-/src/include/conf.h
 a.out
 *.a
 *.so
@@ -16,7 +14,5 @@ a.out
 *.4coder
 *.rdbg
 /.venv
-tinyrt-iface.h
 test/
-test_folder/
 vgcore.*
\ No newline at end of file
diff --git a/src/windows/chkstk.asm b/arch/x86-64/chkstk.asm
similarity index 100%
rename from src/windows/chkstk.asm
rename to arch/x86-64/chkstk.asm
diff --git a/src/loader/loader-entry.asm b/arch/x86-64/loader-entry.asm
similarity index 100%
rename from src/loader/loader-entry.asm
rename to arch/x86-64/loader-entry.asm
diff --git a/build.py b/build.py
index 97326d9..d05b757 100755
--- a/build.py
+++ b/build.py
@@ -1,14 +1,12 @@
 #!/usr/bin/env python3
 
-import argparse # Parsing command-line args
+import importlib
 import platform # Checking current OS
-import shutil
 import os
 import sys
-import pyjson5
 import re
 
-# Colors
+
 class colors:
     grey='\033[38;5;243m'
     cyan='\033[38;5;80m'
@@ -21,219 +19,16 @@ class colors:
 def print_step(step):
     print(f'{colors.green}==>{colors.reset} {step}', end='')
 
-# Parse command line arguments
-arg_parser = argparse.ArgumentParser('build.py')
-arg_parser.add_argument('--clean', action='store_true', help='Remove all object files and binaries')
-arg_parser.add_argument('--test', help='Compile ciabatta executable with given file')
-arg_parser.add_argument('--mode', '-m', choices=['debug', 'release'], default='debug', help='Select build configuration')
-arg_parser.add_argument('--target', '-t', help='Select target OS (default=host)')
-arg_parser.add_argument('--compiler', '-c', choices=['clang', 'cuik'], default='clang', help='Select compiler')
-arg_parser.add_argument('--cflags', nargs='*', default=[], help='Pass additional compiler flags')
-args = arg_parser.parse_args()
-compiler = args.compiler
-
-
-# Perform cleaning if required
-def rm(path):
-    if os.path.exists(path):
-        os.remove(path)
-if args.clean:
-    if os.path.exists('bin'):
-        shutil.rmtree('bin')
-    if os.path.exists('lib'):
-        shutil.rmtree('lib')
-    rm(os.path.join('src', 'ciabatta.c'))
-    rm('a')
-    rm('a.exe')
-    rm('a.ilk')
-    rm('a.pdb')
-    sys.exit(0)
-
-# Check host OS
-print_step('Performing basic checks\n')
-target = args.target
-if target is None:
-    target = platform.system().lower()
-target_colored = f'{colors.cyan}{target}{colors.reset}'
-print(f"  * Compiling for host OS: '{target_colored}'")
-if not os.path.exists(os.path.join('src', target)):
-    print(colors.red, f"  ERROR: OS '{colors.cyan}{target}{colors.red}' isn't implemented.", colors.reset)
-    sys.exit(1)
-
-# Add compiler to dependencies
-dependencies = [
-    'nasm',
-    'llvm-ar'
-]
-dependencies.append(args.compiler)
-
-
-# Figure out the flags
-includes = ['src/include']
-cc = args.compiler
-cc_defines = []
-cc_flags = ['-nostdlib', '-fno-stack-protector']
-crt_file = 'crt.lib'
-lib_file = 'cia.lib'
-dl_file = 'ld-cia.so'
-if args.mode == 'release':
-    cc_flags.append('-O2')
-    cc_defines.append('NDEBUG')
-else: # 'debug'
-    cc_flags.append('-g')
-    cc_flags.append('-O0')
-    cc_defines.append('_DEBUG')
-if target != 'windows':
-    cc_flags.append('-fpic')
-
-if target == 'linux':
-    includes.append('src/include/linux')
-
-# Check dependencies
-print_step('Checking dependencies... ')
-for dependency in dependencies:
-    if shutil.which(dependency) is None:
-        print(colors.red, f"\n  -> [ERROR] Missing dependency: '{dependency}'", colors.reset)
-        sys.exit(1)
-print(colors.green, 'OK', colors.reset)
-
-# Generate TinyRT headers for the target platform
-print_step(f'Generating TinyRT header for: {target_colored}... ')
-tinyrt_config_path = os.path.join('src', target, 'tinyrt.json')
-tinyrt_apis = []
-try:
-    with open(tinyrt_config_path, 'r') as tinyrt_config_file:
-        string = tinyrt_config_file.read()
-        json = '{' + string + '}'
-        tinyrt_config = pyjson5.loads(json)
-except Exception as error:
-    print(colors.red, f"\n  -> [ERROR] reading file '{tinyrt_config_path}'")
-    print(f"  *  {error}", colors.reset)
-    sys.exit(1)
-tinyrt_header_path = os.path.join('src', target, 'tinyrt-iface.h')
-try:
-    with open(tinyrt_header_path, 'w') as tinyrt_header_file:
-        tinyrt_header_file.write('\n')
-        tinyrt_header_file.write(f'// This file is AUTO-GENERATED from {tinyrt_config_path}\n')
-        tinyrt_header_file.write('\n')
-        for tinyrt_api in tinyrt_config:
-            api_name = tinyrt_api
-            is_defined = tinyrt_config[tinyrt_api]
-            if is_defined:
-                tinyrt_apis.append(api_name)
-            is_defined_int = 1 if is_defined else 0
-            tinyrt_header_file.write(f'#define _{api_name.upper()} {is_defined_int}\n')
-except Exception as error:
-    print(colors.red, f"  -> [ERROR] writing to file '{tinyrt_header_path}'")
-    print(f"  *  {error}", colors.reset)
-    sys.exit(1)
-print(colors.green, 'OK', colors.reset)
-
-# Generate ciabatta header for the target platform and configuration
-print_step('Generating ciabatta.c\n')
-library_config_path = os.path.join('src', 'library.json')
-try:
-    with open(library_config_path, 'r') as library_config_file:
-        string = library_config_file.read()
-        json = '{' + string + '}'
-        library_config = pyjson5.loads(json)
-except Exception as error:
-    print(colors.red, f"  ERROR when reading file '{library_config_path}':")
-    print(f"  {error}", colors.reset)
-    sys.exit(1)
-ciabatta_header_path = os.path.join('src', 'ciabatta.c')
-try:
-    with open(ciabatta_header_path, 'w') as ciabatta_header:
-        # Write heading
-        ciabatta_header.write('\n')
-        ciabatta_header.write('// This file is AUTO-GENERATED by library.json\n')
-        ciabatta_header.write('\n')
-        # Write main include
-        ciabatta_header.write('#include <cia-def.h>\n')
-        ciabatta_header.write('\n')
-        # Write platform includes
-        ciabatta_header.write('// Platform-dependent sources\n')
-        platform_config = None
-        for platform in library_config['platforms']:
-            if platform['name'] == target:
-                platform_config = platform
-        if platform_config is None:
-            print(colors.red, f"  ERROR: library config doesn't contain configuration for platform {target}", colors.reset, sep='')
-        for include in platform_config['includes']:
-            include_path = platform_config['path']
-            ciabatta_header.write(f'#include <{include}>\n')
-        for source in platform_config['sources']:
-            source_path = platform_config['path']
-            ciabatta_header.write(f'#include "{source_path}/{source}"\n')
-        ciabatta_header.write(f'#include "{target}/tinyrt-iface.h"\n')
-        ciabatta_header.write(f'#include <tinyrt.h>\n')
-        for tinyrt_source in platform_config['tinyrt']:
-            ciabatta_header.write(f'#include "{target}/{tinyrt_source}"\n')
-        ciabatta_header.write('\n')
-        # Write module includes
-        ciabatta_header.write('// Forward declarations')
-        for include in library_config['includes']:
-            ciabatta_header.write(f'#include <{include}>\n')
-        ciabatta_header.write('\n')
-        # Write module sources
-        mod_exports = []
-        requirements_satisfied = True
-        for api in library_config['apis']:
-            api_name = api['name']
-            api_path = api['path']
-            if api_name in library_config['export']:
-                reqs_satisfied = True
-                # Check API dependencies
-                for req in api['reqs']:
-                    if req in tinyrt_apis:
-                        continue
-                    elif req in mod_exports:
-                        continue
-                    reqs_satisfied = False
-                    break
-                if not reqs_satisfied:
-                    print(colors.red, f"  * Not exporting API '{api_name}'", colors.reset, sep='')
-                    requirements_satisfied = False
-                else:
-                    print(colors.green, f"  * Exporting API '{api_name}'", colors.reset, sep='')
-                    ciabatta_header.write(f'// Module {api_name}\n')
-                    mod_exports.append(api_name)
-                    for include in api['includes']:
-                        ciabatta_header.write(f'#include "{api_path}/{include}"\n')
-        if not requirements_satisfied:
-            sys.exit(1)
-except Exception as error:
-    print(colors.red, f"  ERROR writing file '{ciabatta_header_path}':", sep='')
-    print(f"  {error}", colors.reset)
-    sys.exit(1)
-print_step('Generating cia-conf.h\n')
-
 def path(str):
     l = str.split('/')
     return os.path.join(*l)
+
 def quote(s):
     return '"' + s + '"'
+
 def prefix(prefix):
     return (lambda s: prefix + s)
 
-cc_flags_str = ' '.join(
-               cc_flags +
-               list(map(prefix('-D '), cc_defines)) +
-               list(map(prefix('-I '), map(quote, includes))))
-
-try:
-    with open(os.path.join('src', 'include', 'cia-conf.h'), 'w') as conf_file:
-        os_config = open(os.path.join('src', target, 'conf.h'))
-        conf_file.write('\n')
-        conf_file.write('// This file is AUTO-GENERATED\n')
-        conf_file.write('// See os folder (e.g. src/linux) for conf.h file\n')
-        conf_file.write(os_config.read())
-        os_config.close()
-except Exception as error:
-    print(colors.red, f"  ERROR writing file '{ciabatta_header_path}':", sep='')
-    print(f"  {error}", colors.reset)
-    sys.exit(1)
-
 def run(cmdline):
     cmdline_colored = re.sub(r'"(.+?)"', f'{colors.grey}"\\1"{colors.reset}', cmdline)
     cmdline_colored = re.sub(r'^([a-zA-Z0-9-_]*)', f'{colors.yellow}\\1{colors.reset}', cmdline_colored)
@@ -242,24 +37,36 @@ def run(cmdline):
     if code != 0:
         sys.exit(code)
 
-def assemble(src, out):
-    format = 'elf64'
-    if target == 'windows':
-        format = 'win64'
-    cmdline = f'nasm -f "{format}" "{path(src)}" -o "{path(out)}"'
+cc_flags = []
+cc_defines = []
+cc_includes = []
+
+def compile(output, inputs, additional_flags=[]):
+    flags_cmdline = ' '.join(cc_flags + additional_flags)
+    defines_cmdline = ' '.join(map(prefix('-D '), map(quote, cc_defines)))
+    includes_cmdline = ' '.join(map(prefix('-I '), map(quote, cc_includes)))
+    inputs_cmdline = ' '.join(inputs)
+    cmdline = f'clang {flags_cmdline} {includes_cmdline} {defines_cmdline} {inputs_cmdline} -o {output}'
     run(cmdline)
 
-def compile(srcs, out, extra_flags = ''):
-    if cc == 'cuik' and out.endswith('.o'):
-        out = out[:-2]
-    flags = cc_flags_str + ' ' + extra_flags + ' ' + ' '.join(args.cflags)
-    inputs = ' '.join(map(quote, map(path, srcs)))
-    cmdline = f'{cc} {flags} {inputs} -o {quote(path(out))}'
+def compile_obj(output, inputs, additional_flags=[]):
+    compile(output, inputs, ['-c -fpic'] + additional_flags)
+
+def compile_exe(output, inputs, additional_flags=[]):
+    compile(output, inputs, ['-pie'] + additional_flags)
+
+def compile_shared(output, inputs, additional_flags=[]):
+    compile(output, inputs, ['-shared'] + additional_flags)
+
+def assemble_obj(output, inputs, flags=[]):
+    flags_cmdline = ' '.join(flags)
+    inputs_cmdline = ' '.join(inputs)
+    cmdline = f'nasm {flags_cmdline} {inputs_cmdline} -o {output}'
     run(cmdline)
 
-def archive(srcs, out):
-    inputs = ' '.join(map(quote, srcs))
-    cmdline = f'llvm-ar -rcs {quote(out)} {inputs}'
+def archive(output, inputs):
+    inputs_cmdline = ' '.join(inputs)
+    cmdline = f'llvm-ar -rcs {output} {inputs_cmdline}'
     run(cmdline)
 
 # Ciabatta build spec
@@ -268,46 +75,35 @@ if not os.path.exists('lib'):
 if not os.path.exists('bin'):
     os.mkdir('bin')
 
-cia_lib = f'lib/{lib_file}'
-crt_lib = f'lib/{crt_file}'
-dl_lib = f'lib/{dl_file}'
-
-dl_flags = [
-    '-shared',
-    '-nostdlib',
-    # '-mno-sse',
-    '-ffreestanding',
-    '-fno-stack-protector',
+loader_flags = [
     '-Wl,-e,_dlstart',
     '-Wl,--sort-section,alignment',
     '-Wl,--sort-common',
     '-Wl,--gc-sections',
     '-Wl,--hash-style=both',
     '-Wl,--no-undefined',
-    '-Wl,--exclude-libs=ALL',
+    '-Wl,--exclude-libs=ALL'
 ]
 
-if target == 'linux':
-    print_step(f'Compiling {dl_lib}\n')
-    assemble('src/loader/loader-entry.asm', 'bin/loader-entry.o')
-    compile(['bin/loader-entry.o', 'src/loader/loader-self-reloc.c', 'src/loader/loader.c'], dl_lib,
-        ' '.join(dl_flags))
+target_arch = 'x86-64'
+target_os = 'linux'
 
-print_step(f'Compiling {crt_file}\n')
-if target == 'linux':
-    compile(['src/linux/crt-ctors.c'], 'bin/crt-ctors.o', '-c')
-    archive(['bin/crt-ctors.o'], crt_lib)
-elif target == 'windows':
-    assemble('src/windows/chkstk.asm', 'bin/chkstk.o')
-    compile(['src/windows/crt-entry.c'], 'bin/crt-entry.o', '-c')
-    archive(['bin/crt-entry.o', 'bin/chkstk.o'], crt_lib)
+cc_flags.extend(['-nostdlib', '-fno-stack-protector'])
+cc_flags.extend(['-g', '-O0'])
+cc_defines.append('_DEBUG')
+cc_defines.append(f'_CIA_OS_CONF=\\"os/{target_os}/conf.h\\"')
 
-print_step(f'Compiling {lib_file}\n')
-compile(['src/ciabatta.c'], 'bin/ciabatta.o', '-c')
-archive(['bin/ciabatta.o'], cia_lib)
+cc_includes.append('include')
+cc_includes.append('include/linux')
 
-if args.test:
-    if target == 'linux':
-        compile([args.test, crt_lib, cia_lib], 'a', f'-pie -Wl,-dynamic-linker,{dl_lib} -fno-stack-protector')
-    elif target == 'windows':
-        compile([args.test, crt_lib, cia_lib], 'a.exe', '-lkernel32.lib')
+# Build the dynamic loader
+print_step("Building lib/ld-cia.so\n")
+assemble_obj('bin/loader-entry.o', [f'arch/{target_arch}/loader-entry.asm'], ['-f "elf64"'])
+compile_shared('lib/ld-cia.so', ['bin/loader-entry.o','loader/loader-self-reloc.c','loader/loader.c'], loader_flags)
+
+# Build the ciabatta
+compile_obj('bin/cia.o', ['cia.c'])
+archive('lib/cia.a', ['bin/cia.o'])
+
+# Build the test
+compile_exe('a', ['tests/hello.c', 'lib/cia.a'], ['-Wl,-dynamic-linker,lib/ld-cia.so'])
diff --git a/cia.c b/cia.c
new file mode 100644
index 0000000..2117646
--- /dev/null
+++ b/cia.c
@@ -0,0 +1,26 @@
+
+#include <cia-def.h>
+
+// Platform-dependent sources
+#include _CIA_OS_CONF
+
+// Forward declarations
+#include <stdlib.h>
+#include <stdio.h>
+#include <threads.h>
+#include <cia-mem.h>
+
+// Module cia_memory
+#include "src/cia-mem/util.c"
+#include "src/cia-mem/allocator.c"
+#include "src/cia-mem/arena.c"
+#include "src/cia-mem/pool.c"
+
+// Module stdlib_program
+#include "src/stdlib-program/program.c"
+
+// Module stdlib_threads
+#include "src/stdlib-thread/thread.c"
+
+// Module stdlib_file
+#include "src/stdlib-file/file.c"
diff --git a/commands.sh b/commands.sh
new file mode 100644
index 0000000..59d0aad
--- /dev/null
+++ b/commands.sh
@@ -0,0 +1,10 @@
+==> Compiling lib/ld-cia.so
+  $ nasm -f "elf64" "loader/loader-entry.asm" -o "bin/loader-entry.o"
+  $ clang -nostdlib -fno-stack-protector -g -O0 -fpic -D _DEBUG -I "include" -I "include/linux" -shared -nostdlib -ffreestanding -fno-stack-protector -Wl,-e,_dlstart -Wl,--sort-section,alignment -Wl,--sort-common -Wl,--gc-sections -Wl,--hash-style=both -Wl,--no-undefined -Wl,--exclude-libs=ALL  "bin/loader-entry.o" "loader/loader-self-reloc.c" "loader/loader.c" -o "lib/ld-cia.so"
+==> Compiling crt.lib
+  $ clang -nostdlib -fno-stack-protector -g -O0 -fpic -D _DEBUG -I "include" -I "include/linux" -c  "os/linux/crt-ctors.c" -o "bin/crt-ctors.o"
+  $ llvm-ar -rcs "lib/crt.lib" "bin/crt-ctors.o"
+==> Compiling cia.lib
+  $ clang -nostdlib -fno-stack-protector -g -O0 -fpic -D _DEBUG -I "include" -I "include/linux" -c  "include/cia.c" -o "bin/cia.o"
+  $ llvm-ar -rcs "lib/cia.lib" "bin/cia.o"
+  $ clang -nostdlib -fno-stack-protector -g -O0 -fpic -D _DEBUG -I "include" -I "include/linux" -pie -Wl,-dynamic-linker,lib/ld-cia.so -fno-stack-protector  "tests/hello.c" "lib/crt.lib" "lib/cia.lib" -o "a"
diff --git a/src/include/bin/elf.h b/include/bin/elf.h
similarity index 100%
rename from src/include/bin/elf.h
rename to include/bin/elf.h
diff --git a/src/include/cia-conf.h b/include/cia-conf.h
similarity index 64%
rename from src/include/cia-conf.h
rename to include/cia-conf.h
index 1f6f898..c302c1e 100644
--- a/src/include/cia-conf.h
+++ b/include/cia-conf.h
@@ -2,5 +2,5 @@
 // This file is AUTO-GENERATED
 // See os folder (e.g. src/linux) for conf.h file
 
-#define _CIA_OS_LINUX
-#define _CIA_DATA_LP64
+#define CIA_OS_LINUX
+#define CIA_DATA_LP64
diff --git a/src/include/cia-def.h b/include/cia-def.h
similarity index 100%
rename from src/include/cia-def.h
rename to include/cia-def.h
diff --git a/src/include/cia-mem.h b/include/cia-mem.h
similarity index 100%
rename from src/include/cia-mem.h
rename to include/cia-mem.h
diff --git a/src/include/ctype.h b/include/ctype.h
similarity index 100%
rename from src/include/ctype.h
rename to include/ctype.h
diff --git a/src/include/errno.h b/include/errno.h
similarity index 100%
rename from src/include/errno.h
rename to include/errno.h
diff --git a/src/include/linux/fcntl.h b/include/linux/fcntl.h
similarity index 100%
rename from src/include/linux/fcntl.h
rename to include/linux/fcntl.h
diff --git a/src/include/linux/sched.h b/include/linux/sched.h
similarity index 100%
rename from src/include/linux/sched.h
rename to include/linux/sched.h
diff --git a/src/include/linux/sys/mman.h b/include/linux/sys/mman.h
similarity index 100%
rename from src/include/linux/sys/mman.h
rename to include/linux/sys/mman.h
diff --git a/src/include/linux/sys/syscall.h b/include/linux/sys/syscall.h
similarity index 100%
rename from src/include/linux/sys/syscall.h
rename to include/linux/sys/syscall.h
diff --git a/src/include/stdbool.h b/include/stdbool.h
similarity index 100%
rename from src/include/stdbool.h
rename to include/stdbool.h
diff --git a/src/include/stddef.h b/include/stddef.h
similarity index 100%
rename from src/include/stddef.h
rename to include/stddef.h
diff --git a/src/include/stdint.h b/include/stdint.h
similarity index 92%
rename from src/include/stdint.h
rename to include/stdint.h
index 5ee6a51..f0b80ed 100644
--- a/src/include/stdint.h
+++ b/include/stdint.h
@@ -5,9 +5,9 @@ static_assert(sizeof(char) == 1, "Char isn't 1 bytes long");
 static_assert(sizeof(short) == 2, "Short isn't 2 bytes long");
 static_assert(sizeof(int) == 4, "Int isn't 4 bytes long");
 static_assert(sizeof(long long int) == 8, "Long long isn't 8 bytes long");
-#if defined(_CIA_DATA_LP64)
+#if defined(CIA_DATA_LP64)
     static_assert(sizeof(long) == 8, "Long on linux isn't 8 bytes");
-#elif defined(_CIA_DATA_LLP64)
+#elif defined(CIA_DATA_LLP64)
     static_assert(sizeof(long) == 4, "Long on windows isn't 4 bytes");
 #endif
 
@@ -17,10 +17,10 @@ typedef signed short int16_t;
 typedef unsigned short uint16_t;
 typedef signed int int32_t;
 typedef unsigned int uint32_t;
-#if defined(_CIA_DATA_LP64)
+#if defined(CIA_DATA_LP64)
     typedef signed long int64_t;
     typedef unsigned long uint64_t;
-#elif defined(_CIA_DATA_LLP64)
+#elif defined(CIA_DATA_LLP64)
     typedef signed long long int64_t;
     typedef unsigned long long uint64_t;
 #else
@@ -50,12 +50,12 @@ typedef uint64_t uintptr_t;
 #define UINT16_C(n)  (n)
 #define UINT32_C(n)  (n)
 
-#if defined(_CIA_DATA_LP64)
+#if defined(CIA_DATA_LP64)
     #define INT64_C(n)   (n ## L)
     #define INTMAX_C(n)  (n ## L)
     #define UINT64_C(n)  (n ## UL)
     #define UINTMAX_C(n) (n ## UL)
-#elif defined(_CIA_DATA_LLP64)
+#elif defined(CIA_DATA_LLP64)
     #define INT64_C(n)   (n ## LL)
     #define INTMAX_C(n)  (n ## LL)
     #define UINT64_C(n)  (n ## ULL)
diff --git a/src/include/stdio.h b/include/stdio.h
similarity index 100%
rename from src/include/stdio.h
rename to include/stdio.h
diff --git a/src/include/stdlib.h b/include/stdlib.h
similarity index 100%
rename from src/include/stdlib.h
rename to include/stdlib.h
diff --git a/src/include/string.h b/include/string.h
similarity index 100%
rename from src/include/string.h
rename to include/string.h
diff --git a/src/include/threads.h b/include/threads.h
similarity index 100%
rename from src/include/threads.h
rename to include/threads.h
diff --git a/src/include/tinyrt.h b/include/tinyrt.h
similarity index 61%
rename from src/include/tinyrt.h
rename to include/tinyrt.h
index 7c50a0e..7d93f9a 100644
--- a/src/include/tinyrt.h
+++ b/include/tinyrt.h
@@ -41,9 +41,7 @@ static _RT_Status _rt_init();
 static _RT_Status _rt_deinit();
 
 // Program API
-#if _RT_API_PROGRAM == 1
-    _Noreturn static void _rt_program_exit(int code);
-#endif
+_Noreturn static void _rt_program_exit(int code);
 
 // Thread API
 struct _RT_Thread typedef _RT_Thread;
@@ -51,21 +49,17 @@ struct _RT_Thread {
     u64 tid;
     void *handle;
 };
-#if _RT_API_THREAD == 1
-    static _RT_Status _rt_thread_current(_RT_Thread *thread);
-    static _RT_Status _rt_thread_create(_RT_Thread *thread, void (*thread_fn)(void *ctx), void *ctx);
-    static _RT_Status _rt_thread_join(_RT_Thread *thread);
-    static _RT_Status _rt_thread_detach(_RT_Thread *thread);
-    static _RT_Status _rt_thread_terminate(_RT_Thread *thread);
-    static _RT_Status _rt_thread_sleep(u64 time);
-    static _RT_Status _rt_thread_get_timer_freq(u64 *freq);
-#endif
+static _RT_Status _rt_thread_current(_RT_Thread *thread);
+static _RT_Status _rt_thread_create(_RT_Thread *thread, void (*thread_fn)(void *ctx), void *ctx);
+static _RT_Status _rt_thread_join(_RT_Thread *thread);
+static _RT_Status _rt_thread_detach(_RT_Thread *thread);
+static _RT_Status _rt_thread_terminate(_RT_Thread *thread);
+static _RT_Status _rt_thread_sleep(u64 time);
+static _RT_Status _rt_thread_get_timer_freq(u64 *freq);
 
 // Environment API
-#if _RT_API_ENVIRONMENT == 1
-    static _RT_Status _rt_shell_exec(char const *cmd);
-    static _RT_Status _rt_env_get(char const *name);
-#endif
+static _RT_Status _rt_shell_exec(char const *cmd);
+static _RT_Status _rt_env_get(char const *name);
 
 // File API
 struct _RT_File typedef _RT_File;
@@ -76,19 +70,15 @@ struct _RT_File {
     };
     i32 flags;
 };
-#if _RT_API_FILE == 1
-    static _RT_File _rt_file_stdin;
-    static _RT_File _rt_file_stdout;
-    static _RT_File _rt_file_stderr;
-    static _RT_Status _rt_file_std_handles_init();
-    static _RT_Status _rt_file_open(_RT_File *file, char const *name, int flags);
-    static _RT_Status _rt_file_read(u64 size, void *buffer, _RT_File *from, u64 *out_bytes_read);
-    static _RT_Status _rt_file_write(_RT_File *to, u64 size, void *buffer, u64 *out_bytes_written);
-    static _RT_Status _rt_file_close(_RT_File *file);
-#endif
+static _RT_File _rt_file_stdin;
+static _RT_File _rt_file_stdout;
+static _RT_File _rt_file_stderr;
+static _RT_Status _rt_file_std_handles_init();
+static _RT_Status _rt_file_open(_RT_File *file, char const *name, int flags);
+static _RT_Status _rt_file_read(u64 size, void *buffer, _RT_File *from, u64 *out_bytes_read);
+static _RT_Status _rt_file_write(_RT_File *to, u64 size, void *buffer, u64 *out_bytes_written);
+static _RT_Status _rt_file_close(_RT_File *file);
 
 // Memory API
-#if _RT_API_MEMORY == 1
-    static _RT_Status _rt_mem_alloc(void *optional_desired_addr, u64 size, void **out_addr);
-    static _RT_Status _rt_mem_free(void *ptr, u64 size);
-#endif
+static _RT_Status _rt_mem_alloc(void *optional_desired_addr, u64 size, void **out_addr);
+static _RT_Status _rt_mem_free(void *ptr, u64 size);
diff --git a/src/loader/loader-self-reloc.c b/loader/loader-self-reloc.c
similarity index 100%
rename from src/loader/loader-self-reloc.c
rename to loader/loader-self-reloc.c
diff --git a/src/loader/loader.c b/loader/loader.c
similarity index 97%
rename from src/loader/loader.c
rename to loader/loader.c
index 165b75d..911fe43 100644
--- a/src/loader/loader.c
+++ b/loader/loader.c
@@ -9,15 +9,14 @@
 #include <sched.h>
 #include <errno.h>
 #include <fcntl.h>
-#include "../linux/tinyrt-iface.h"
 #include <tinyrt.h>
-#include "../linux/tinyrt.c"
+#include "../os/linux/tinyrt.c"
 
 #include <cia-mem.h>
-#include "../impl/cia-mem/util.c"
-#include "../impl/cia-mem/allocator.c"
-#include "../impl/cia-mem/arena.c"
-#include "../impl/cia-mem/pool.c"
+#include "../src/cia-mem/util.c"
+#include "../src/cia-mem/allocator.c"
+#include "../src/cia-mem/arena.c"
+#include "../src/cia-mem/pool.c"
 
 struct Elf_Image typedef Elf_Image;
 struct Elf_Image {
diff --git a/src/loader/loader.h b/loader/loader.h
similarity index 100%
rename from src/loader/loader.h
rename to loader/loader.h
diff --git a/os/linux/build.py b/os/linux/build.py
new file mode 100644
index 0000000..ab9312b
--- /dev/null
+++ b/os/linux/build.py
@@ -0,0 +1,24 @@
+
+loader_flags = [
+    '-Wl,-e,_dlstart',
+    '-Wl,--sort-section,alignment',
+    '-Wl,--sort-common',
+    '-Wl,--gc-sections',
+    '-Wl,--hash-style=both',
+    '-Wl,--no-undefined',
+    '-Wl,--exclude-libs=ALL'
+]
+
+def build(toolchain):
+    toolchain.compiler.flags.append('-fno-stack-protector')
+    toolchain.assembler.flags.append('-f "elf64"')
+    compiler = toolchain.compiler
+    assembler = toolchain.assembler
+    archiver = toolchain.archiver
+    # Build dynamic loader
+    toolchain.step("lib/ld-cia.so")
+    assembler.obj('bin/loader-entry.o', ['loader/loader-entry.asm'])
+    compiler.shared('lib/ld-cia.so', ['bin/loader-entry.c','loader/loader-self-reloc.c','loader/loader.c'], loader_flags)
+    # Build the crt
+    toolchain.step('crt.lib')
+    compiler.obj('')
\ No newline at end of file
diff --git a/os/linux/conf.h b/os/linux/conf.h
new file mode 100644
index 0000000..482dc6b
--- /dev/null
+++ b/os/linux/conf.h
@@ -0,0 +1,11 @@
+
+#pragma once
+
+#include <sys/mman.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include "entry.c"
+#include <tinyrt.h>
+#include "tinyrt.c"
+
diff --git a/src/linux/crt-ctors.c b/os/linux/crt-ctors.c
similarity index 100%
rename from src/linux/crt-ctors.c
rename to os/linux/crt-ctors.c
diff --git a/src/linux/entry.c b/os/linux/entry.c
similarity index 96%
rename from src/linux/entry.c
rename to os/linux/entry.c
index b9dac28..fe63f79 100644
--- a/src/linux/entry.c
+++ b/os/linux/entry.c
@@ -14,7 +14,7 @@ void __stack_chk_fail(void) {
 extern int main(int argc, char **argv, char **envp);
 static void _fileapi_init();
 
-void _cia_start() {
+void _start() {
     // Get the envp
     // char **envp = argv + (argc + 1);
     // init(argc, argv, envp);
diff --git a/src/linux/tinyrt.c b/os/linux/tinyrt.c
similarity index 100%
rename from src/linux/tinyrt.c
rename to os/linux/tinyrt.c
diff --git a/src/windows/cia-init.c b/os/windows/cia-init.c
similarity index 100%
rename from src/windows/cia-init.c
rename to os/windows/cia-init.c
diff --git a/src/windows/conf.h b/os/windows/conf.h
similarity index 100%
rename from src/windows/conf.h
rename to os/windows/conf.h
diff --git a/src/windows/crt-entry.c b/os/windows/crt-entry.c
similarity index 100%
rename from src/windows/crt-entry.c
rename to os/windows/crt-entry.c
diff --git a/src/windows/tinyrt.c b/os/windows/tinyrt.c
similarity index 100%
rename from src/windows/tinyrt.c
rename to os/windows/tinyrt.c
diff --git a/src/windows/tinyrt.json b/os/windows/tinyrt.json
similarity index 100%
rename from src/windows/tinyrt.json
rename to os/windows/tinyrt.json
diff --git a/utf8/utf8.rc b/os/windows/utf8/utf8.rc
similarity index 100%
rename from utf8/utf8.rc
rename to os/windows/utf8/utf8.rc
diff --git a/utf8/utf8.xml b/os/windows/utf8/utf8.xml
similarity index 100%
rename from utf8/utf8.xml
rename to os/windows/utf8/utf8.xml
diff --git a/src/windows/windows.c b/os/windows/windows.c
similarity index 100%
rename from src/windows/windows.c
rename to os/windows/windows.c
diff --git a/readme.md b/readme.md
index a17a453..668e9b2 100644
--- a/readme.md
+++ b/readme.md
@@ -98,22 +98,8 @@ $ pip install pyjson5
 
 ### Building
 
-On linux you can simply run `./build.lua` script. On windows you have to run
-it like `lua build.lua`. Reference for command-line options:
-
-```
-Usage: build.py [-h] [--clean] [--test TEST]
-                [--mode {debug,release}] [--target TARGET]
-                [--compiler {clang,cuik}] [--cflags [CFLAGS ...]]
-Options:
-  -h, --help                  show this help message and exit
-  --clean                     Remove all object files and binaries
-  --test TEST                 Compile ciabatta executable with given file
-  --mode, -m {debug,release}  Select build configuration
-  --target, -t TARGET         Select target OS (default=host)
-  --compiler, -c {clang,cuik} Select compiler
-  --cflags [CFLAGS ...]       Pass additional compiler flags
-```
+On linux you can simply run `./build.py` script. On windows can run
+it with `py build.py` command.
 
 ## Usage
 
@@ -131,7 +117,7 @@ assuming you put all files mentioned above in the `./ciabatta` folder
 1. Add the following flags to your compilation command:
    `-nostdlib -I ./ciabatta/include utf8.obj -mfma`
 2. Add the following sources to the compile command:
-   `./ciabatta/lib/ciabatta.lib ./ciabatta/lib/cia.lib ./ciabatta/lib/crt.lib`
+   `./ciabatta/lib/cia.lib`
 
 **Note:** The `include` folder refers to the folder you copied from ciabatta. Set the path to it accordingly.
 
@@ -140,7 +126,9 @@ assuming you put all files mentioned above in the `./ciabatta` folder
 1. Add the following flags to your compilation command:
    - `-nostdlib -I ./ciabatta/include -mfma`
 2. Link to the following libraries
-   - `./ciabatta/lib/ciabatta.a`
+   - `./ciabatta/lib/cia.a`
+3. Specify the ciabatta dynamic loader in linker options
+   - `-Wl,-dynamic-linker,lib/ld-cia.so`
 
 ## Contributing
 
diff --git a/src/impl/cia-mem/allocator.c b/src/cia-mem/allocator.c
similarity index 100%
rename from src/impl/cia-mem/allocator.c
rename to src/cia-mem/allocator.c
diff --git a/src/impl/cia-mem/arena.c b/src/cia-mem/arena.c
similarity index 100%
rename from src/impl/cia-mem/arena.c
rename to src/cia-mem/arena.c
diff --git a/src/impl/cia-mem/pool.c b/src/cia-mem/pool.c
similarity index 100%
rename from src/impl/cia-mem/pool.c
rename to src/cia-mem/pool.c
diff --git a/src/impl/cia-mem/util.c b/src/cia-mem/util.c
similarity index 100%
rename from src/impl/cia-mem/util.c
rename to src/cia-mem/util.c
diff --git a/src/library.json b/src/library.json
deleted file mode 100644
index 194d50e..0000000
--- a/src/library.json
+++ /dev/null
@@ -1,118 +0,0 @@
-// Manifest file for the ciabatta build.
-
-// Platform sections describe available platforms and
-// which files they need to include to function
-// API sections describe API subsets and their TinyRT
-// dependencies. If an API requires TinyRT module that
-// isn't implemented by the platform that API won't be included
-// in the final build
-
-// This file is used to auto-generate ciabatta.c
-
-// `include` section specifies the header files that ciabatta
-//   implements
-// `platform` sections describe platforms, the directories
-//   where the source code for these platforms resides and the
-//   files that should be included in the build for that platform
-//   (relative to "src" dir) as well as the location of TinyRT
-//   implementation.
-// `api` sections describe modules, where the implementation resides,
-//   the source files and the TinyRT modules, on which this module
-//   depends. If the platform doesn't implement one of the dependencies
-//   this module will not be included in the final build
-
-includes: [
-    "stdlib.h",
-    "stdio.h",
-    "threads.h",
-    "cia-mem.h",
-],
-
-platforms: [
-    {
-        name: "linux",
-        path: "linux",
-        includes: [
-            "sys/mman.h",
-            "errno.h",
-            "fcntl.h",
-            "sched.h",
-        ],
-        sources: [
-            "entry.c",
-        ],
-        tinyrt: [
-            "tinyrt.c"
-        ]
-    },
-    {
-        name: "windows",
-        path: "windows",
-        sources: [
-            "windows.c"
-        ],
-        tinyrt: [
-            "tinyrt.c",
-            "cia-init.c"
-        ],
-    },
-],
-
-apis: [
-    {
-        name: "cia_memory",
-        path: "impl/cia-mem",
-        includes: [
-            "util.c",
-            "allocator.c",
-            "arena.c",
-            "pool.c",
-        ],
-        reqs: [
-            "rt_api_memory"
-        ]
-    },
-    {
-        name: "stdlib_program",
-        path: "impl/stdlib-program",
-        includes: [
-            "program.c",
-        ],
-        reqs: [
-            "rt_api_program",
-            "cia_memory",
-        ]
-    },
-    {
-        name: "stdlib_threads",
-        path: "impl/stdlib-thread",
-        includes: [
-            "thread.c",
-        ],
-        reqs: [
-            "rt_api_thread"
-        ]
-    },
-    {
-        name: "stdlib_file",
-        path: "impl/stdlib-file",
-        includes: [
-            "file.c"
-        ],
-        reqs: [
-            "rt_api_file",
-            "cia_memory",
-        ]
-    }
-],
-
-// Edit this part for a particular build you want
-// this contains list of "name" properties for modules
-// in the "apis" section
-
-export: [
-    "cia_memory",
-    "stdlib_program",
-    "stdlib_file",
-    "stdlib_threads",
-]
\ No newline at end of file
diff --git a/src/linux/conf.h b/src/linux/conf.h
deleted file mode 100644
index d64652c..0000000
--- a/src/linux/conf.h
+++ /dev/null
@@ -1,3 +0,0 @@
-
-#define _CIA_OS_LINUX
-#define _CIA_DATA_LP64
diff --git a/src/linux/tinyrt.json b/src/linux/tinyrt.json
deleted file mode 100644
index bfd4281..0000000
--- a/src/linux/tinyrt.json
+++ /dev/null
@@ -1,11 +0,0 @@
-
-// This file contains TinyRT API subsets that are exported
-// for this operating system, one name per line. This file
-// is used in a build script to generate tinyrt_macro file
-// and to resolve higher-level API dependencies
-
-rt_api_file: true,
-rt_api_program: true,
-rt_api_shell: false,
-rt_api_memory: true,
-rt_api_thread: true,
diff --git a/src/impl/stdlib-file/file.c b/src/stdlib-file/file.c
similarity index 100%
rename from src/impl/stdlib-file/file.c
rename to src/stdlib-file/file.c
diff --git a/src/impl/stdlib-program/program.c b/src/stdlib-program/program.c
similarity index 100%
rename from src/impl/stdlib-program/program.c
rename to src/stdlib-program/program.c
diff --git a/src/impl/stdlib-thread/thread.c b/src/stdlib-thread/thread.c
similarity index 100%
rename from src/impl/stdlib-thread/thread.c
rename to src/stdlib-thread/thread.c