diff --git a/make/common.mk b/make/common.mk
index 7cfb509e..4ad785b3 100644
--- a/make/common.mk
+++ b/make/common.mk
@@ -7,6 +7,9 @@ COMMON_MK_INCLUDED           = true
 
 Q                           ?= @
 INTERACTIVE                 ?= auto
+ifndef WHICH
+  WHICH                     := command -v
+endif
 BROWSER                     ?= xdg-open
 JWB_SCRIPT_DIR              ?= $(firstword $(wildcard $(JWBDIR)/scripts $(JWBDIR)/bin) jwb-script-dir-not-found)
 
diff --git a/make/defs.mk b/make/defs.mk
index 78f856ca..277fc2de 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -11,9 +11,6 @@ include $(JWBDIR)/make/projects.mk
 
 # ----- Executables
 
-ifndef WHICH
-  WHICH                     := $(firstword $(wildcard /usr/bin/which) $(shell which which))
-endif
 ifndef GREP
   GREP                      := $(shell $(WHICH) grep)
 endif
diff --git a/make/projects-dir.mk b/make/projects-dir.mk
index 09b60335..9d8a5f50 100644
--- a/make/projects-dir.mk
+++ b/make/projects-dir.mk
@@ -115,7 +115,7 @@ endif
 
 EDITOR                      ?= xdg-open
 ifeq ($(TIME),)
-  TIME                      := $(shell which time)
+  TIME                      := $(shell $(WHICH) time)
   ifneq ($(TIME),)
     TIME                    += -p
   endif
diff --git a/make/py-check.mk b/make/py-check.mk
index 35e5fc30..4970e792 100644
--- a/make/py-check.mk
+++ b/make/py-check.mk
@@ -23,7 +23,7 @@ ifndef PY_CHECK_MYPY
 endif
 
 ifndef PY_CHECK_RUFF
-  PY_CHECK_RUFF             := $(shell which ruff 2>/dev/null)
+  PY_CHECK_RUFF             := $(shell $(WHICH) ruff 2>/dev/null)
   ifneq ($(PY_CHECK_RUFF),)
     PY_CHECK_RUFF           += --config $(TOPDIR)/pyproject.toml
   endif
@@ -38,7 +38,7 @@ ifndef PY_CHECK_YAPF
 endif
 
 ifndef PY_CHECK_PYRIGHT
-  PY_CHECK_PYRIGHT          := $(shell which pyright 2>/dev/null)
+  PY_CHECK_PYRIGHT          := $(shell $(WHICH) pyright 2>/dev/null)
   TD_GENERATE_FILES         += pyrightconfig.json
 endif
 
diff --git a/make/py-version.mk b/make/py-version.mk
index c705891a..3e4ec0dc 100644
--- a/make/py-version.mk
+++ b/make/py-version.mk
@@ -6,7 +6,7 @@ ifneq ($(PYTHON_VERSION),)
 else
   ifeq ($(PYTHON),)
     #PYTHON                  := $(lastword $(shell /bin/bash -O extglob -c "ls -v /usr/bin/python[0-9].+([0-9])"))
-    PYTHON                  := $(shell which python3 | xargs readlink -f)
+    PYTHON                  := $(shell $(WHICH) python3 | xargs readlink -f)
   endif
   PYTHON_VERSION            ?= $(patsubst python%,%,$(notdir $(PYTHON)))
 endif