diff --git a/make/projects.mk b/make/projects.mk
index d6717b81..5d2c91c1 100644
--- a/make/projects.mk
+++ b/make/projects.mk
@@ -27,12 +27,15 @@ ifndef WHICH
   WHICH                     := $(firstword $(wildcard /usr/bin/which) $(shell which which))
 endif
 
-ifeq ($(PYTHON),)
-  PYTHON_VERSION            := 3
-  PYTHON                    := $(shell $(WHICH) python$(PYTHON_VERSION))
+ifneq ($(PYTHON_VERSION),)
+  PYTHON                    := /usr/bin/python$(PYTHON_VERSION)
 else
-  PYTHON_VERSION            := $(word 2,$(subst ., ,$(shell $(PYTHON) --version)))
+  ifeq ($(PYTHON),)
+    PYTHON                  := $(lastword $(shell ls -v /usr/bin/python[0-9]*))
+  endif
+  PYTHON_VERSION            ?= $(patsubst python%,%,$(notdir $(PYTHON)))
 endif
+PYTHON_MAJOR                 = $(basename $(PYTHON_VERSION))
 
 ifneq ($(TOPDIR),)
   proj_query_cmd             = $(PYTHON) $(JWB_SCRIPT_DIR)/projects.py -p $(PROJECTS_DIR) -t $(TOPDIR) $(PROJECTS_PY_EXTRA_ARGS)
diff --git a/make/py-defs.mk b/make/py-defs.mk
index 23e616f4..6cb92979 100644
--- a/make/py-defs.mk
+++ b/make/py-defs.mk
@@ -1,9 +1,11 @@
 ENV_PYTHONPATH              := $(PYTHONPATH)
 
-ifeq ($(PYTHON),)
-  PYTHON_VERSION            ?= 3
-  PYTHON                    ?= /usr/bin/python$(PYTHON_VERSION)
+ifneq ($(PYTHON_VERSION),)
+  PYTHON                    := /usr/bin/python$(PYTHON_VERSION)
 else
+  ifeq ($(PYTHON),)
+    PYTHON                  := $(lastword $(shell ls -v /usr/bin/python[0-9]*))
+  endif
   PYTHON_VERSION            ?= $(patsubst python%,%,$(notdir $(PYTHON)))
 endif
 PYTHON_MAJOR                 = $(basename $(PYTHON_VERSION))