--- Makefile	2023-12-07 09:38:24.000000000 +0800
+++ Makefile	2025-12-11 23:15:30.000000000 +0800
@@ -5,12 +5,7 @@
 CXX      ?= g++
 CXXFLAGS ?= -O2 -fpermissive
 INSTALL  ?= install
-INSTALL_PROGRAM ?= $(INSTALL) -D
-
-# https://www.gnu.org/prep/standards/html_node/Directory-Variables.html#Directory-Variables
-prefix      ?= /usr/local
-exec_prefix ?= $(prefix)
-bindir      ?= $(exec_prefix)/bin
+INSTALL_PROGRAM ?= $(INSTALL)
 
 override CXXFLAGS += -std=c++2a -Wall -fexceptions
 override LDFLAGS  += -pthread
@@ -23,7 +18,7 @@
 	$(CXX) $(LDFLAGS) $^ -o $@ $(LOADLIBES) $(LDLIBS)
 
 install: all
-	$(INSTALL_PROGRAM) $(PROGNAME) $(DESTDIR)$(bindir)/$(PROGNAME)
+	$(INSTALL_PROGRAM) $(PROGNAME) $(DESTDIR)$(PREFIX)/bin/$(PROGNAME)
 
 clean:
 	$(RM) -f $(PROGNAME) *.o