diff --git a/catboost/python-package/setup.py b/catboost/python-package/setup.py
index fe9251a21f..86b880c5d0 100644
--- a/catboost/python-package/setup.py
+++ b/catboost/python-package/setup.py
@@ -80,7 +80,7 @@ class Helper(object):
         self.with_cuda = os.environ.get('CUDA_PATH') or os.environ.get('CUDA_ROOT') or None
         self.os_sdk = 'local'
         self.with_ymake = True
-        self.parallel = None
+        self.parallel = os.environ.get('NIX_BUILD_CORES') or None
 
     def finalize_options(self):
         if os.path.exists(str(self.with_cuda)):
@@ -222,11 +222,12 @@ class build_ext(_build_ext):
 
     def build_with_make(self, topsrc_dir, build_dir, catboost_ext, put_dir, verbose, dry_run):
         logging.info('Buildling {} with gnu make'.format(catboost_ext))
-        makefile = 'python{}.{}CLANG11-LINUX-X86_64.makefile'.format(python_version()[0], 'CUDA.' if self.with_cuda else '')
+        makefile = 'python{}.{}CLANG12-LINUX-X86_64.makefile'.format(python_version()[0], 'CUDA.' if self.with_cuda else '')
         make_cmd = [
             'make', '-f', '../../make/' + makefile,
-            'CC=clang-11',
-            'CXX=clang++-11',
+            'CC=clang',
+            'CXX=clang++',
+            'PYTHON=python{}'.format(python_version()[0]),
             'BUILD_ROOT=' + build_dir,
             'SOURCE_ROOT=' + topsrc_dir,
         ]
diff --git a/make/python2.CLANG12-LINUX-X86_64.makefile b/make/python2.CLANG12-LINUX-X86_64.makefile
index b49a36fb3f..33996af995 100644
--- a/make/python2.CLANG12-LINUX-X86_64.makefile
+++ b/make/python2.CLANG12-LINUX-X86_64.makefile
@@ -4,31 +4,6 @@ BUILD_ROOT = $(shell pwd)
 SOURCE_ROOT = $(shell pwd)
 PYTHON = $(shell which python)
 
-ifneq ($(MAKECMDGOALS),help)
-define _CC_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CC_VERSION = $(shell echo '$(_CC_TEST)' | $(CC) -E -P -)
-$(info _CC_VERSION = '$(_CC_VERSION)')
-
-ifneq '$(_CC_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
-
-ifneq ($(MAKECMDGOALS),help)
-define _CXX_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CXX_VERSION = $(shell echo '$(_CXX_TEST)' | $(CXX) -E -P -)
-$(info _CXX_VERSION = '$(_CXX_VERSION)')
-
-ifneq '$(_CXX_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
 
 
 all\
diff --git a/make/python2.CUDA.CLANG12-LINUX-X86_64.makefile b/make/python2.CUDA.CLANG12-LINUX-X86_64.makefile
index 82935b297e..093cc86532 100644
--- a/make/python2.CUDA.CLANG12-LINUX-X86_64.makefile
+++ b/make/python2.CUDA.CLANG12-LINUX-X86_64.makefile
@@ -4,31 +4,6 @@ BUILD_ROOT = $(shell pwd)
 SOURCE_ROOT = $(shell pwd)
 PYTHON = $(shell which python)
 
-ifneq ($(MAKECMDGOALS),help)
-define _CC_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CC_VERSION = $(shell echo '$(_CC_TEST)' | $(CC) -E -P -)
-$(info _CC_VERSION = '$(_CC_VERSION)')
-
-ifneq '$(_CC_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
-
-ifneq ($(MAKECMDGOALS),help)
-define _CXX_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CXX_VERSION = $(shell echo '$(_CXX_TEST)' | $(CXX) -E -P -)
-$(info _CXX_VERSION = '$(_CXX_VERSION)')
-
-ifneq '$(_CXX_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
 
 
 all\
diff --git a/make/python3.CLANG12-LINUX-X86_64.makefile b/make/python3.CLANG12-LINUX-X86_64.makefile
index 1c5d646ae4..6c091fbe17 100644
--- a/make/python3.CLANG12-LINUX-X86_64.makefile
+++ b/make/python3.CLANG12-LINUX-X86_64.makefile
@@ -4,31 +4,6 @@ BUILD_ROOT = $(shell pwd)
 SOURCE_ROOT = $(shell pwd)
 PYTHON = $(shell which python)
 
-ifneq ($(MAKECMDGOALS),help)
-define _CC_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CC_VERSION = $(shell echo '$(_CC_TEST)' | $(CC) -E -P -)
-$(info _CC_VERSION = '$(_CC_VERSION)')
-
-ifneq '$(_CC_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
-
-ifneq ($(MAKECMDGOALS),help)
-define _CXX_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CXX_VERSION = $(shell echo '$(_CXX_TEST)' | $(CXX) -E -P -)
-$(info _CXX_VERSION = '$(_CXX_VERSION)')
-
-ifneq '$(_CXX_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
 
 
 all\
diff --git a/make/python3.CUDA.CLANG12-LINUX-X86_64.makefile b/make/python3.CUDA.CLANG12-LINUX-X86_64.makefile
index fcdb75a719..4e1dbc3cd7 100644
--- a/make/python3.CUDA.CLANG12-LINUX-X86_64.makefile
+++ b/make/python3.CUDA.CLANG12-LINUX-X86_64.makefile
@@ -4,31 +4,6 @@ BUILD_ROOT = $(shell pwd)
 SOURCE_ROOT = $(shell pwd)
 PYTHON = $(shell which python)
 
-ifneq ($(MAKECMDGOALS),help)
-define _CC_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CC_VERSION = $(shell echo '$(_CC_TEST)' | $(CC) -E -P -)
-$(info _CC_VERSION = '$(_CC_VERSION)')
-
-ifneq '$(_CC_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
-
-ifneq ($(MAKECMDGOALS),help)
-define _CXX_TEST
-__clang_major__ __clang_minor__
-endef
-
-_CXX_VERSION = $(shell echo '$(_CXX_TEST)' | $(CXX) -E -P -)
-$(info _CXX_VERSION = '$(_CXX_VERSION)')
-
-ifneq '$(_CXX_VERSION)' '12 0'
-    $(error clang 12.0 is required)
-endif
-endif
 
 
 all\