diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4f31d298a5f77a76e5ed1596899a09ff25410270..d5a48b880c34c2666db0157f0f45dd1269afc37d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Updated PV-names to be ESS compliant, and remove VERSIONS PV
 * Changed from `build number` to `revision number`
 * Added revision number parsing for test versions
+* Joined together the variables `REQUIRE_CONFIG` and `E3_REQUIRE_CONFIG`
+* Removed legacy file `DECOUPLE_FLAGS`
 
 ## [4.0.0]
 
diff --git a/configure/CONFIG b/configure/CONFIG
index a6dee79e334d2aba7959af5ea78d788a403851a9..b3d650f07c67ae31830eddcc99668a4f2e709c85 100644
--- a/configure/CONFIG
+++ b/configure/CONFIG
@@ -19,16 +19,16 @@ endif
 
 
 E3_MODULES_PATH:=$(EPICS_BASE)
-REQUIRE_CONFIG:=$(TOP)/configure/E3
+E3_REQUIRE_CONFIG:=$(TOP)/configure/E3
 
 include $(EPICS_BASE)/configure/CONFIG_BASE_VERSION
-include $(REQUIRE_CONFIG)/CONFIG_REQUIRE
-include $(REQUIRE_CONFIG)/CONFIG_SHELL
-include $(REQUIRE_CONFIG)/CONFIG_E3_PATH
-include $(REQUIRE_CONFIG)/CONFIG_E3_MAKEFILE
-include $(REQUIRE_CONFIG)/CONFIG_TEST
-include $(REQUIRE_CONFIG)/CONFIG_EPICS
-include $(REQUIRE_CONFIG)/CONFIG_EXPORT
+include $(E3_REQUIRE_CONFIG)/CONFIG_REQUIRE
+include $(E3_REQUIRE_CONFIG)/CONFIG_SHELL
+include $(E3_REQUIRE_CONFIG)/CONFIG_E3_PATH
+include $(E3_REQUIRE_CONFIG)/CONFIG_E3_MAKEFILE
+include $(E3_REQUIRE_CONFIG)/CONFIG_TEST
+include $(E3_REQUIRE_CONFIG)/CONFIG_EPICS
+include $(E3_REQUIRE_CONFIG)/CONFIG_EXPORT
 
 # Exclude generated EPICS base variables from make vars report.
 VARS_EXCLUDES+=BASE_3_14
diff --git a/configure/E3/CONFIG b/configure/E3/CONFIG
index ef6702b6bf64daa9a18128870d6d956c3d9dd347..21e2b5815b7c3cfdaf6540bfa3fcfbf60965f1db 100644
--- a/configure/E3/CONFIG
+++ b/configure/E3/CONFIG
@@ -4,17 +4,18 @@
 E3_MODULE_VERSION:=$(E3_MODULE_VERSION)$(shell (echo "$(E3_MODULE_VERSION)" | grep -Eq "^[0-9]+\.[0-9]+\.[0-9]+\$$") && echo +0)
 
 E3_MODULES_PATH?=$(E3_SITEMODS_PATH)
+E3_REQUIRE_CONFIG:=$(E3_REQUIRE_LOCATION)/configure
 
 include $(EPICS_BASE)/configure/CONFIG_BASE_VERSION
-include $(REQUIRE_CONFIG)/CONFIG_REQUIRE
-include $(REQUIRE_CONFIG)/CONFIG_SHELL
-include $(REQUIRE_CONFIG)/CONFIG_CELL
-include $(REQUIRE_CONFIG)/CONFIG_TEST
-include $(REQUIRE_CONFIG)/CONFIG_E3_PATH
-include $(REQUIRE_CONFIG)/CONFIG_E3_MAKEFILE
-include $(REQUIRE_CONFIG)/CONFIG_EPICS
-include $(REQUIRE_CONFIG)/CONFIG_DKMS
-include $(REQUIRE_CONFIG)/CONFIG_EXPORT
+include $(E3_REQUIRE_CONFIG)/CONFIG_REQUIRE
+include $(E3_REQUIRE_CONFIG)/CONFIG_SHELL
+include $(E3_REQUIRE_CONFIG)/CONFIG_CELL
+include $(E3_REQUIRE_CONFIG)/CONFIG_TEST
+include $(E3_REQUIRE_CONFIG)/CONFIG_E3_PATH
+include $(E3_REQUIRE_CONFIG)/CONFIG_E3_MAKEFILE
+include $(E3_REQUIRE_CONFIG)/CONFIG_EPICS
+include $(E3_REQUIRE_CONFIG)/CONFIG_DKMS
+include $(E3_REQUIRE_CONFIG)/CONFIG_EXPORT
 
 VARS_EXCLUDES+=BASE_3_14
 VARS_EXCLUDES+=BASE_3_15
diff --git a/configure/E3/CONFIG_REQUIRE b/configure/E3/CONFIG_REQUIRE
index 045f42b54ef166f16c597e6cd6a34b3af31a235c..ea565b0e1b41dccfcdd0fa17f7e3c863fa638f54 100644
--- a/configure/E3/CONFIG_REQUIRE
+++ b/configure/E3/CONFIG_REQUIRE
@@ -10,4 +10,3 @@ E3_REQUIRE_LIB:=$(E3_REQUIRE_LOCATION)/lib
 E3_REQUIRE_DB:=$(E3_REQUIRE_LOCATION)/db
 E3_REQUIRE_DBD:=$(E3_REQUIRE_LOCATION)/dbd
 E3_REQUIRE_INC:=$(E3_REQUIRE_LOCATION)/include
-E3_REQUIRE_CONFIG:=$(E3_REQUIRE_LOCATION)/configure
diff --git a/configure/E3/DECOUPLE_FLAGS b/configure/E3/DECOUPLE_FLAGS
deleted file mode 100644
index befe8edba9bb76f94f1ee1c8b853f5e0f5744068..0000000000000000000000000000000000000000
--- a/configure/E3/DECOUPLE_FLAGS
+++ /dev/null
@@ -1 +0,0 @@
-# Legacy file. Needed since <module>.Makefiles include this.
diff --git a/configure/E3/RULES_E3 b/configure/E3/RULES_E3
index 1557dc26a0283143667abf370906f7a021934650..879aafae9963b3eaeab1bbe04b4f7e7dd8e69ca2 100644
--- a/configure/E3/RULES_E3
+++ b/configure/E3/RULES_E3
@@ -76,7 +76,7 @@ clean: conf
 all: init patch rebuild
 
 # Copy $(E3_MODULE_MAKEFILE) into $(E3_MODULE_SRC_PATH)
-include $(REQUIRE_CONFIG)/RULES_CHECKS
+include $(E3_REQUIRE_CONFIG)/RULES_CHECKS
 conf: consistency_checks
 	$(QUIET) install -p -m 644 $(TOP)/$(E3_MODULE_MAKEFILE)  $(E3_MODULE_SRC_PATH)/
 
diff --git a/configure/E3/RULES_SITEMODS b/configure/E3/RULES_SITEMODS
index 3313189aedb9970021c3760aedf0c44f88ffb5b8..833326b14ea31da07a544d0a41d1c88301847aa2 100644
--- a/configure/E3/RULES_SITEMODS
+++ b/configure/E3/RULES_SITEMODS
@@ -1,12 +1,12 @@
 # -*- mode: Makefile;-*-
 
-include $(REQUIRE_CONFIG)/RULES_E3
-include $(REQUIRE_CONFIG)/RULES_CELL
-include $(REQUIRE_CONFIG)/DEFINES_FT
-include $(REQUIRE_CONFIG)/RULES_PATCH
-include $(REQUIRE_CONFIG)/RULES_TEST
+include $(E3_REQUIRE_CONFIG)/RULES_E3
+include $(E3_REQUIRE_CONFIG)/RULES_CELL
+include $(E3_REQUIRE_CONFIG)/DEFINES_FT
+include $(E3_REQUIRE_CONFIG)/RULES_PATCH
+include $(E3_REQUIRE_CONFIG)/RULES_TEST
 
-include $(REQUIRE_CONFIG)/RULES_DKMS
-include $(REQUIRE_CONFIG)/RULES_VARS
+include $(E3_REQUIRE_CONFIG)/RULES_DKMS
+include $(E3_REQUIRE_CONFIG)/RULES_VARS
 
-include $(REQUIRE_CONFIG)/RULES_DEV
+include $(E3_REQUIRE_CONFIG)/RULES_DEV
diff --git a/configure/RULES b/configure/RULES
index 01475baa5aa2094e4c0fd34920beb7b8ca6d55cd..8a070461648d5c2c9671e5bed544091772c5941a 100644
--- a/configure/RULES
+++ b/configure/RULES
@@ -1,21 +1,21 @@
 # -*- mode: Makefile;-*-
 # include $(EPICS_BASE)/configure/RULES
 
-include $(REQUIRE_CONFIG)/DEFINES_FT
+include $(E3_REQUIRE_CONFIG)/DEFINES_FT
 #
 # We cannot use file operation in CentOS7.4,
 # because Makefile version is 3.8.
-include $(REQUIRE_CONFIG)/RULES_E3
-include $(REQUIRE_CONFIG)/RULES_EPICS
+include $(E3_REQUIRE_CONFIG)/RULES_E3
+include $(E3_REQUIRE_CONFIG)/RULES_EPICS
 
 
 include $(TOP)/configure/module/RULES_REQUIRE
 
-include $(REQUIRE_CONFIG)/RULES_PATCH
-include $(REQUIRE_CONFIG)/RULES_VARS
+include $(E3_REQUIRE_CONFIG)/RULES_PATCH
+include $(E3_REQUIRE_CONFIG)/RULES_VARS
 include $(TOP)/configure/module/RULES_TEST
 
 
 ifneq (,$(findstring dev,$(MAKECMDGOALS)))
-include $(REQUIRE_CONFIG)/RULES_DEV
+include $(E3_REQUIRE_CONFIG)/RULES_DEV
 endif
diff --git a/configure/module/RULES_REQUIRE b/configure/module/RULES_REQUIRE
index a054636a09f823c8e7fc46bb602e5da6f772336d..2370898e099c2e8694bde66e05978660e9dc8e96 100644
--- a/configure/module/RULES_REQUIRE
+++ b/configure/module/RULES_REQUIRE
@@ -28,13 +28,13 @@ requireconf: e3-site-path e3-require-path
 	$(QUIET) install    -m 755 $(E3_MODULE_SRC_PATH)/tools/revision_number       $(E3_REQUIRE_TOOLS)/
 	$(QUIET) install    -m 755 $(E3_SHELL_FILES)             $(E3_REQUIRE_BIN)/
 	$(QUIET) install    -m 644 $(E3_IOC_CFG_FILES)           $(E3_REQUIRE_BIN)/
-	$(QUIET) install    -m 644 $(E3_REQUIRE_CONF_FILES)      $(E3_REQUIRE_CONFIG)/
+	$(QUIET) install    -m 644 $(E3_REQUIRE_CONF_FILES)      $(E3_REQUIRE_LOCATION)/configure/
 
 
 e3-require-path:
 	$(QUIET) install -d -m 755 $(E3_REQUIRE_TOOLS)
 	$(QUIET) install -d -m 755 $(E3_REQUIRE_BIN)
-	$(QUIET) install -d -m 755 $(E3_REQUIRE_CONFIG)
+	$(QUIET) install -d -m 755 $(E3_REQUIRE_LOCATION)/configure
 
 
 e3-site-path: