diff --git a/inc/wolf-py-tests/wolfcrypt-py-enable-tests-legacy.inc b/inc/wolf-py-tests/wolfcrypt-py-enable-tests-legacy.inc
index 86e56b0..53f66c8 100644
--- a/inc/wolf-py-tests/wolfcrypt-py-enable-tests-legacy.inc
+++ b/inc/wolf-py-tests/wolfcrypt-py-enable-tests-legacy.inc
@@ -1,33 +1,19 @@
 # Enable test directory installation for wolfcrypt-py
 #
-# This include file configures wolfcrypt-py to install its test directory
-# to the target system for running Python binding tests.
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 
 WOLFCRYPT_PY_TEST_DIR = "${S}"
 WOLFCRYPT_PY_DIR = "/home/root/wolf-py-tests/wolfcrypt-py-test"
 WOLFCRYPT_PY_TEST_TARGET_DIR = "${D}${WOLFCRYPT_PY_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfcrypt_py_test_dir = d.getVar('WOLFCRYPT_PY_TEST_DIR', True)
-    wolfcrypt_py_test_target_dir = d.getVar('WOLFCRYPT_PY_TEST_TARGET_DIR', True)
-
-    installDirCmd = 'install -m 0755 -d "%s"\n' % wolfcrypt_py_test_target_dir
-    cpWolfcryptPyTestCmd = 'cp -r %s/* %s\n' % (wolfcrypt_py_test_dir, wolfcrypt_py_test_target_dir)
-
-    d.appendVar('do_install', installDirCmd)
-    d.appendVar('do_install', cpWolfcryptPyTestCmd)
-
-    pn = d.getVar('PN', True)
-    wolfcrypt_py_dir = d.getVar('WOLFCRYPT_PY_DIR', True)
-
-    # Legacy always uses underscore syntax
-    files_var_name = 'FILES_' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfcrypt_py_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install_append() {
+    install -m 0755 -d "${WOLFCRYPT_PY_TEST_TARGET_DIR}"
+    cp -r ${WOLFCRYPT_PY_TEST_DIR}/* ${WOLFCRYPT_PY_TEST_TARGET_DIR}
 }
 
+FILES_wolfcrypt-py += "${WOLFCRYPT_PY_DIR}/*"
+
 # Python Specific option
 export PYTHONDONTWRITEBYTECODE = "1"
diff --git a/inc/wolf-py-tests/wolfcrypt-py-enable-tests-modern.inc b/inc/wolf-py-tests/wolfcrypt-py-enable-tests-modern.inc
index a128fcc..8fb78d3 100644
--- a/inc/wolf-py-tests/wolfcrypt-py-enable-tests-modern.inc
+++ b/inc/wolf-py-tests/wolfcrypt-py-enable-tests-modern.inc
@@ -1,35 +1,19 @@
 # Enable test directory installation for wolfcrypt-py
 #
-# This include file configures wolfcrypt-py to install its test directory
-# to the target system for running Python binding tests.
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 
 WOLFCRYPT_PY_TEST_DIR = "${S}"
 WOLFCRYPT_PY_DIR = "/home/root/wolf-py-tests/wolfcrypt-py-test"
 WOLFCRYPT_PY_TEST_TARGET_DIR = "${D}${WOLFCRYPT_PY_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfcrypt_py_test_dir = d.getVar('WOLFCRYPT_PY_TEST_DIR', True)
-    wolfcrypt_py_test_target_dir = d.getVar('WOLFCRYPT_PY_TEST_TARGET_DIR', True)
-
-    installDirCmd = 'install -m 0755 -d "%s"\n' % wolfcrypt_py_test_target_dir
-    cpWolfcryptPyTestCmd = 'cp -r %s/* %s\n' % (wolfcrypt_py_test_dir, wolfcrypt_py_test_target_dir)
-
-    d.appendVar('do_install', installDirCmd)
-    d.appendVar('do_install', cpWolfcryptPyTestCmd)
-
-    pn = d.getVar('PN', True)
-    wolfcrypt_py_dir = d.getVar('WOLFCRYPT_PY_DIR', True)
-
-    if distro_version and (distro_version.startswith('2.') or distro_version.startswith('3.')):
-        files_var_name = 'FILES_' + pn
-    else:
-        files_var_name = 'FILES:' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfcrypt_py_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install:append() {
+    install -m 0755 -d "${WOLFCRYPT_PY_TEST_TARGET_DIR}"
+    cp -r ${WOLFCRYPT_PY_TEST_DIR}/* ${WOLFCRYPT_PY_TEST_TARGET_DIR}
 }
 
+FILES:wolfcrypt-py += "${WOLFCRYPT_PY_DIR}/*"
+
 # Python Specific option
 export PYTHONDONTWRITEBYTECODE = "1"
diff --git a/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-legacy.inc b/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-legacy.inc
index 694b0e8..5d9a00b 100644
--- a/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-legacy.inc
+++ b/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-legacy.inc
@@ -1,5 +1,9 @@
 # Configuration to enable wolf-py-tests support in wolfssl
 # Python tests may need specific features enabled
+#
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 EXTRA_OECONF += "--enable-shared"
 
 WOLFSSL_PY_TEST_CERTS_DIR = "/home/root/wolf-py-tests/certs"
@@ -7,27 +11,11 @@ WOLFSSL_PY_CERTS_DIR = "/certs"
 WOLFSSL_PY_CERTS_INSTALL_DIR = "${D}${WOLFSSL_PY_TEST_CERTS_DIR}"
 WOLFSSL_PY_CERTS_SOURCE_DIR = "${S}${WOLFSSL_PY_CERTS_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfssl_py_certs_install_dir = d.getVar('WOLFSSL_PY_CERTS_INSTALL_DIR', True)
-    wolfssl_py_certs_source_dir = d.getVar('WOLFSSL_PY_CERTS_SOURCE_DIR', True)
-
-    bbnote = 'bbnote "Installing Certs Directory for wolf-py Tests"\n'
-    installDir = 'install -m 0755 -d "%s"\n' % (wolfssl_py_certs_install_dir)
-    cpDer = 'cp -r %s/*.der %s\n' % (wolfssl_py_certs_source_dir, wolfssl_py_certs_install_dir)
-    cpPem = 'cp -r %s/*.pem %s\n' % (wolfssl_py_certs_source_dir, wolfssl_py_certs_install_dir)
-
-    d.appendVar('do_install', bbnote)
-    d.appendVar('do_install', installDir)
-    d.appendVar('do_install', cpDer)
-    d.appendVar('do_install', cpPem)
-
-    pn = d.getVar('PN', True)
-    wolfssl_py_test_certs_dir = d.getVar('WOLFSSL_PY_TEST_CERTS_DIR', True)
-    # Legacy always uses underscore syntax
-    files_var_name = 'FILES_' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfssl_py_test_certs_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install_append() {
+    bbnote "Installing Certs Directory for wolf-py Tests"
+    install -m 0755 -d "${WOLFSSL_PY_CERTS_INSTALL_DIR}"
+    cp -r ${WOLFSSL_PY_CERTS_SOURCE_DIR}/*.der ${WOLFSSL_PY_CERTS_INSTALL_DIR}
+    cp -r ${WOLFSSL_PY_CERTS_SOURCE_DIR}/*.pem ${WOLFSSL_PY_CERTS_INSTALL_DIR}
 }
+
+FILES_wolfssl += "${WOLFSSL_PY_TEST_CERTS_DIR}/*"
diff --git a/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-modern.inc b/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-modern.inc
index efc75ec..f641b2e 100644
--- a/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-modern.inc
+++ b/inc/wolf-py-tests/wolfssl-enable-wolf-py-tests-modern.inc
@@ -1,5 +1,9 @@
 # Configuration to enable wolf-py-tests support in wolfssl
 # Python tests may need specific features enabled
+#
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 EXTRA_OECONF += "--enable-shared"
 
 WOLFSSL_PY_TEST_CERTS_DIR = "/home/root/wolf-py-tests/certs"
@@ -7,29 +11,11 @@ WOLFSSL_PY_CERTS_DIR = "/certs"
 WOLFSSL_PY_CERTS_INSTALL_DIR = "${D}${WOLFSSL_PY_TEST_CERTS_DIR}"
 WOLFSSL_PY_CERTS_SOURCE_DIR = "${S}${WOLFSSL_PY_CERTS_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfssl_py_certs_install_dir = d.getVar('WOLFSSL_PY_CERTS_INSTALL_DIR', True)
-    wolfssl_py_certs_source_dir = d.getVar('WOLFSSL_PY_CERTS_SOURCE_DIR', True)
-
-    bbnote = 'bbnote "Installing Certs Directory for wolf-py Tests"\n'
-    installDir = 'install -m 0755 -d "%s"\n' % (wolfssl_py_certs_install_dir)
-    cpDer = 'cp -r %s/*.der %s\n' % (wolfssl_py_certs_source_dir, wolfssl_py_certs_install_dir)
-    cpPem = 'cp -r %s/*.pem %s\n' % (wolfssl_py_certs_source_dir, wolfssl_py_certs_install_dir)
-
-    d.appendVar('do_install', bbnote)
-    d.appendVar('do_install', installDir)
-    d.appendVar('do_install', cpDer)
-    d.appendVar('do_install', cpPem)
-
-    pn = d.getVar('PN', True)
-    wolfssl_py_test_certs_dir = d.getVar('WOLFSSL_PY_TEST_CERTS_DIR', True)
-    if distro_version and (distro_version.startswith('2.') or distro_version.startswith('3.')):
-        files_var_name = 'FILES_' + pn
-    else:
-        files_var_name = 'FILES:' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfssl_py_test_certs_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install:append() {
+    bbnote "Installing Certs Directory for wolf-py Tests"
+    install -m 0755 -d "${WOLFSSL_PY_CERTS_INSTALL_DIR}"
+    cp -r ${WOLFSSL_PY_CERTS_SOURCE_DIR}/*.der ${WOLFSSL_PY_CERTS_INSTALL_DIR}
+    cp -r ${WOLFSSL_PY_CERTS_SOURCE_DIR}/*.pem ${WOLFSSL_PY_CERTS_INSTALL_DIR}
 }
+
+FILES:wolfssl += "${WOLFSSL_PY_TEST_CERTS_DIR}/*"
diff --git a/inc/wolf-py-tests/wolfssl-py-enable-tests-legacy.inc b/inc/wolf-py-tests/wolfssl-py-enable-tests-legacy.inc
index 4ec6259..550193d 100644
--- a/inc/wolf-py-tests/wolfssl-py-enable-tests-legacy.inc
+++ b/inc/wolf-py-tests/wolfssl-py-enable-tests-legacy.inc
@@ -1,34 +1,19 @@
 # Enable test directory installation for wolfssl-py
 #
-# This include file configures wolfssl-py to install its test directory
-# to the target system for running Python binding tests.
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 
 WOLFSSL_PY_TEST_DIR = "${S}"
 WOLFSSL_PY_DIR = "/home/root/wolf-py-tests/wolfssl-py-test"
 WOLFSSL_PY_TEST_TARGET_DIR = "${D}${WOLFSSL_PY_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfssl_py_test_dir = d.getVar('WOLFSSL_PY_TEST_DIR', True)
-    wolfssl_py_test_target_dir = d.getVar('WOLFSSL_PY_TEST_TARGET_DIR', True)
-
-    installDir = 'install -m 0755 -d "%s"\n' % (wolfssl_py_test_target_dir)
-    cpWolfsslPyTest = 'cp -r %s/* %s\n' % (wolfssl_py_test_dir, wolfssl_py_test_target_dir)
-
-    d.appendVar('do_install', installDir)
-    d.appendVar('do_install', cpWolfsslPyTest)
-
-    # Append to FILES_${PN} within the Python function
-    pn = d.getVar('PN', True)
-    wolfssl_py_dir = d.getVar('WOLFSSL_PY_DIR', True)
-
-    # Legacy always uses underscore syntax
-    files_var_name = 'FILES_' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfssl_py_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install_append() {
+    install -m 0755 -d "${WOLFSSL_PY_TEST_TARGET_DIR}"
+    cp -r ${WOLFSSL_PY_TEST_DIR}/* ${WOLFSSL_PY_TEST_TARGET_DIR}
 }
 
+FILES_wolfssl-py += "${WOLFSSL_PY_DIR}/*"
+
 # Python Specific option
 export PYTHONDONTWRITEBYTECODE = "1"
diff --git a/inc/wolf-py-tests/wolfssl-py-enable-tests-modern.inc b/inc/wolf-py-tests/wolfssl-py-enable-tests-modern.inc
index 1b229a2..7753626 100644
--- a/inc/wolf-py-tests/wolfssl-py-enable-tests-modern.inc
+++ b/inc/wolf-py-tests/wolfssl-py-enable-tests-modern.inc
@@ -1,36 +1,19 @@
 # Enable test directory installation for wolfssl-py
 #
-# This include file configures wolfssl-py to install its test directory
-# to the target system for running Python binding tests.
+# Declarative on purpose: this inc is included by wolfssl_conditional_require()
+# from an anonymous function, and python () blocks registered that late never
+# run. FILES uses the literal package name because expandKeys() has already run.
 
 WOLFSSL_PY_TEST_DIR = "${S}"
 WOLFSSL_PY_DIR = "/home/root/wolf-py-tests/wolfssl-py-test"
 WOLFSSL_PY_TEST_TARGET_DIR = "${D}${WOLFSSL_PY_DIR}"
 
-python () {
-    distro_version = d.getVar('DISTRO_VERSION', True)
-    wolfssl_py_test_dir = d.getVar('WOLFSSL_PY_TEST_DIR', True)
-    wolfssl_py_test_target_dir = d.getVar('WOLFSSL_PY_TEST_TARGET_DIR', True)
-
-    installDir = 'install -m 0755 -d "%s"\n' % (wolfssl_py_test_target_dir)
-    cpWolfsslPyTest = 'cp -r %s/* %s\n' % (wolfssl_py_test_dir, wolfssl_py_test_target_dir)
-
-    d.appendVar('do_install', installDir)
-    d.appendVar('do_install', cpWolfsslPyTest)
-
-    # Append to FILES:${PN} within the Python function
-    pn = d.getVar('PN', True)
-    wolfssl_py_dir = d.getVar('WOLFSSL_PY_DIR', True)
-
-    if distro_version and (distro_version.startswith('2.') or distro_version.startswith('3.')):
-        files_var_name = 'FILES_' + pn
-    else:
-        files_var_name = 'FILES:' + pn
-
-    current_files = d.getVar(files_var_name, True) or ""
-    new_files = current_files + ' ' + wolfssl_py_dir + '/*'
-    d.setVar(files_var_name, new_files)
+do_install:append() {
+    install -m 0755 -d "${WOLFSSL_PY_TEST_TARGET_DIR}"
+    cp -r ${WOLFSSL_PY_TEST_DIR}/* ${WOLFSSL_PY_TEST_TARGET_DIR}
 }
 
+FILES:wolfssl-py += "${WOLFSSL_PY_DIR}/*"
+
 # Python Specific option
 export PYTHONDONTWRITEBYTECODE = "1"