diff --git a/lfric_macros/__init__.py b/lfric_macros/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/lfric_macros/apply_macros.py b/lfric_macros/apply_macros.py
new file mode 100755
index 0000000..d3385e4
--- /dev/null
+++ b/lfric_macros/apply_macros.py
@@ -0,0 +1,998 @@
+#!/usr/bin/env python3
+##############################################################################
+# (c) Crown copyright 2024 Met Office. All rights reserved.
+# The file LICENCE, distributed with this code, contains details of the terms
+# under which the code may be used.
+##############################################################################
+"""
+Script for lfric_apps upgrade macros. Pre-processes the macros and then applies
+them to rose-stem apps.
+Warning: Should only be run on a Test branch or by CR on commit to trunk
+"""
+
+import os
+import re
+import shutil
+import argparse
+import tempfile
+import subprocess
+
+BLACK_COMMAND = "black --line-length=80"
+CLASS_NAME_REGEX = r"vn\d+_t\d+\w."
+TAG_REGEX = r"\s*=\s*[\"']\s*(\S+)\s*[\"']"
+
+
+def run_command(command, shell=False):
+    """
+    Run a subprocess command and return the result object
+    Inputs:
+        - command, str with command to run
+    Outputs:
+        - result object from subprocess.run
+    """
+    if not shell:
+        command = command.split()
+    return subprocess.run(
+        command,
+        capture_output=True,
+        text=True,
+        timeout=120,
+        shell=shell,
+        check=False,
+    )
+
+
+def get_root_path(apps_path):
+    """
+    Given a path to a working copy, ensure the path and working copy are both
+    valid and return the path to the working copy root directory
+    Inputs:
+        - apps_path, command line argument to the apps working copy
+    Outputs:
+        - str, path to the top level of the apps working copy
+    """
+
+    # Run fcm info on the given path to ensure it is
+    command = f"fcm info {apps_path}"
+    result = run_command(command)
+    if result.returncode:
+        raise FileNotFoundError(
+            f"The provided LFRic Apps source, '{apps_path}', was not a valid "
+            "working copy. Please either run this script from within an LFRic "
+            "Apps working copy, or provide a path using the -a argument."
+        )
+
+    # If no error, then search through output for the working copy root path
+    # return the found path
+    for line in result.stdout.split("\n"):
+        if line.startswith("Working Copy Root Path"):
+            return line.split(":", 1)[1].strip()
+
+
+def run_black(filepath):
+    """
+    Run black on a given file
+    Inputs:
+        - filepath, the path to the file to run black on
+    """
+    result = run_command(f"{BLACK_COMMAND} {filepath}")
+    if result.returncode:
+        raise RuntimeError(
+            "Running 'black' as a subprocess failed. This may indicate a "
+            "syntax error with your macro.\nThe error message produced "
+            f"was:\n\n{result.stderr}"
+        )
+
+
+def read_versions_file(meta_dir):
+    """
+    Read in a versions.py and parse out blank lines
+    Inputs:
+        - meta_dir, the path to a directory containing a versions.py file
+    Returns:
+        - a list of lines in the versions.py file with blank lines removed
+    """
+
+    version_file = os.path.join(meta_dir, "versions.py")
+
+    # Read in versions file and then remove all blank lines
+    with open(version_file) as f:
+        file_raw = f.readlines()
+    file_parsed = []
+    for line in file_raw:
+        if len(line.strip().strip("\n")) > 0:
+            file_parsed.append(line)
+
+    return file_parsed
+
+
+def split_macros(parsed_versions):
+    """
+    Read through a versions.py file and split macros into individual strings
+    Inputs:
+        - parsed_versions, a list of lines from a versions.py file with blank
+          lines removed
+    Returns:
+        - a list of strings of individual macros
+    """
+
+    # construct a string for each macro and save in macros list
+    macros = []
+    macro = ""
+    in_macro = False
+    in_comment = False
+    for line in parsed_versions:
+        if '"""' in line:
+            for _ in range(line.count('"""')):
+                in_comment = not in_comment
+        if in_comment:
+            continue
+        if line.startswith("class vn"):
+            if macro:
+                macros.append(macro)
+            in_macro = True
+            macro = ""
+        if in_macro:
+            macro += line
+    if macro:
+        macros.append(macro)
+
+    return macros
+
+
+def match_python_import(line):
+    """
+    Return true if string has form 'import *' or 'from * import *'
+    Inputs:
+        - line, str to match
+    """
+    if re.match(r"import \w+", line) or re.match(
+        r"from [\.\w]+ import [\.\w]+", line
+    ):
+        return True
+    return False
+
+
+def banner_print(message):
+    """Print a simple banner message"""
+    print(f"\n{(len(message)+4)*'*'}\n* {message} *\n{(len(message)+4)*'*'}\n")
+
+
+class ApplyMacros:
+    """
+    Object to hold data + methods to apply upgrade macros in lfric_apps
+    """
+
+    def __init__(self, tag, apps, core, jules):
+        self.tag = tag
+        # The class name is the After Tag with the . removed from the version
+        self.class_name = tag.replace(".", "")
+        self.temp_dirs = {}
+        self.root_path = get_root_path(apps)
+        self.core_source = self.get_dependency_paths(core, "lfric_core")
+        self.jules_source = self.get_dependency_paths(jules, "jules")
+        self.set_rose_meta_path()
+        self.version = re.search(r".*vn(\d+\.\d+)_.*", tag).group(1)
+        self.ticket_number = None
+        self.author = None
+        self.parsed_macros = {}
+        self.meta_dirs = []
+        self.apps_with_macro = []
+        self.python_imports = set()
+        self.upgraded_core = False
+
+    def set_rose_meta_path(self):
+        """
+        Set up the ROSE_META_PATH environment variable in order to use the Jules
+        and Core metadata. We also add the working copy root path as this should
+        allow the script to be run from anywhere
+        """
+        rose_meta_path = (
+            f"{self.root_path}:{self.core_source}:{self.jules_source}"
+        )
+        os.environ["ROSE_META_PATH"] = rose_meta_path
+
+    def parse_application_section(self, meta_dir):
+        """
+        Given a path to a metadata directory, parse out the application/science
+        section. Try to remove the apps, core and jules root paths. Then try to
+        remove trailing /HEAD or /versions.py
+        Inputs:
+            - meta_dir, path to a metadata dir
+        Returns:
+            - path to the metadata directory with the root path removed
+        """
+        meta_dir = meta_dir.removeprefix(self.root_path + "/")
+        meta_dir = meta_dir.removeprefix(self.core_source + "/")
+        meta_dir = meta_dir.removeprefix(self.jules_source + "/")
+
+        meta_dir = meta_dir.removesuffix("/HEAD")
+        meta_dir = meta_dir.removesuffix("/versions.py")
+
+        return meta_dir
+
+    ############################################################################
+    # Get Working Copy Functions
+    ############################################################################
+
+    def get_dependency_paths(self, source, repo):
+        """
+        Parse the core or jules command line arguments to get the path to a
+        working copy.
+        If the source isn't defined, first populate the source by reading the
+        dependencies.sh file.
+        If the source is an fcm url check it out to a temporary location
+        Inputs:
+            - source, str, The command line argument for the source. If not set
+                           this will be None
+            - repo, str, Either "lfric_core" or "jules" depending on which
+                         source is being found
+        Outputs:
+            - str, The path to the source working copy to use
+        """
+
+        # If source is None then read the dependencies.sh file for the source
+        if source is None:
+            source = self.read_dependencies(repo)
+
+        # If the source exists as a path then return as is
+        if os.path.exists(source):
+            return source
+        if ":" in source:
+            source_path = source.split(":")[1]
+            if os.path.exists(source_path):
+                return source_path
+
+        # Check that the source looks like an fcm keyword, raise an error if not
+        if "fcm:" not in source:
+            raise RuntimeError(
+                f"The {repo} source: {source}, was not found as a working copy "
+                "and does not look like an fcm url. Please check the source."
+                "If not set on the command then the dependencies.sh file is "
+                "being used."
+            )
+
+        # Checkout the fcm source to a temporary location
+        source = self.fcm_temp_copy(source, repo)
+        return source
+
+    def read_dependencies(self, repo):
+        """
+        Read through the dependencies.sh file for the source of the repo defined
+        by repo. Assumes this file is in rose-stem/bin and gets the
+        dependencies.sh path from that.
+        Inputs:
+            - repo, str, Either "lfric_core" or "jules" depending on which
+                         source is being found
+        Outputs:
+            - str, The source as defined by the dependencies.sh file
+        """
+        dependencies_path = os.path.join(self.root_path, "dependencies.sh")
+        source = ""
+        rev = ""
+        with open(dependencies_path, "r") as dependencies_file:
+            # Loop over lines in dependencies.sh for lines relevant to repo
+            for line in dependencies_file:
+                line = line.strip()
+                if line.startswith(f"export {repo}_rev"):
+                    rev = line.split("=")[1]
+                if line.startswith(f"export {repo}_sources"):
+                    source = line.split("=")[1]
+        # If source not set then default to trunk
+        if source == "":
+            # lfric_core doesn't match the url
+            if repo == "lfric_core":
+                source = "fcm:lfric.xm_tr"
+            else:
+                source = f"fcm:{repo}.xm_tr"
+        # If a revision set then append to source
+        # Defaults to the head of the source
+        # Only do this if it's an fcm url
+        if rev != "" and "fcm:" in source:
+            source = f"{source}@{rev}"
+        return source
+
+    def fcm_temp_copy(self, url, repo):
+        """
+        Given an fcm url as a source, checkout a working copy to a temp location
+        and return the path. Update self.temp_dirs with temporary directory path
+        Inputs:
+            - url, str, An fcm url of the source
+            - repo, str, the name of the source being found
+        Outputs:
+            - str, The path to the temporary working copy
+        """
+
+        print(f"Extracting {url} to a temporary directory")
+        tempdir = tempfile.mkdtemp()
+        self.temp_dirs[repo] = tempdir
+        command = f"fcm co {url} {tempdir}"
+        result = run_command(command)
+        if result.returncode:
+            raise RuntimeError(
+                f"Failed to checkout from URL {url} into directory {tempdir} "
+                f"with error message:\n\n{result.stderr}"
+            )
+        return tempdir
+
+    ############################################################################
+    # Preprocess Macros Functions
+    ############################################################################
+
+    def find_meta_dirs(self, path):
+        """
+        Searching from a working copy root path, return a list of paths to all
+        the rose-meta firectories using the "find" command. Search by looking
+        for versions.py files
+        Outputs:
+            - str, stdout of find command looking for versions.py files
+        """
+
+        command = f"find {path} -name versions.py"
+        result = run_command(command)
+        if result.returncode:
+            raise RuntimeError(
+                "Error while finding versions.py files in the directory "
+                f"{path}. Running command '{command}'\nError:\n\n"
+                f"{result.stderr}\n"
+            )
+        meta_dirs = result.stdout.split("\n")
+        for item in meta_dirs:
+            item = item.removesuffix("/versions.py")
+            if item:
+                self.meta_dirs.append(item)
+
+    def parse_macro(self, macro, meta_dir):
+        """
+        Given a macro string save the macro info in a dictionary
+        Inputs:
+            - macro, an upgrade macro that matches the class name we are
+              looking for
+            - meta_dir, the path to the rose metadata directory
+        """
+
+        version_file = os.path.join(meta_dir, "versions.py")
+
+        # The ticket number and author will always be the same across all
+        # macros for this ticket, so only grab these once
+        # These are not vital so don't fail if not found
+        if self.ticket_number is None or self.author is None:
+            ticket_details = re.search(r"Upgrade .* (#\d+) by (\S+.*)", macro)
+            try:
+                self.ticket_number = ticket_details.group(1)
+                self.author = ticket_details.group(2).rstrip('".')
+                self.author = self.author.strip("<>")
+            except AttributeError:
+                pass
+
+        # Search for the before tag
+        # Raise an exception if these are missing
+        try:
+            before_tag = re.search(rf"BEFORE_TAG{TAG_REGEX}", macro).group(1)
+        except AttributeError as exc:
+            raise RuntimeError(
+                "Couldn't find either a Before tag for the requested "
+                f"macro in the file {version_file}"
+            ) from exc
+
+        # Finally extract the lines which are defining the commands run by the
+        # macro. Record these as a single block as each command may be over
+        # multiple lines
+        in_function = False
+        commands = ""
+        for line in macro.split("\n"):
+            line_stripped = line.strip()
+            if line_stripped.startswith("def upgrade(self"):
+                in_function = True
+                continue
+            if (
+                line_stripped.startswith("return")
+                or line_stripped.startswith("# Input your macro commands here")
+                or line_stripped.lower().startswith("# add settings")
+            ):
+                continue
+            if not in_function or line_stripped.startswith("return config"):
+                continue
+            commands += line + "\n"
+
+        # Record macro details
+        self.parsed_macros[meta_dir] = {
+            "before_tag": before_tag,
+            "commands": commands,
+        }
+
+    def remove_macro(self, contents, meta_dir):
+        """
+        Rewrite the contents of a versions.py file without the newly added
+        macro. Run black on the new file.
+        Inputs:
+            - contents, list of lines from the original file
+            - meta_dir, the path to the versions.py file being rewritten
+        """
+
+        filepath = os.path.join(meta_dir, "versions.py")
+
+        with open(filepath, "w") as f:
+            in_new_macro = False
+            for line in contents:
+                if re.match(r"class vn\d+_t\d+", line):
+                    if in_new_macro:
+                        in_new_macro = False
+                    elif self.class_name in line:
+                        in_new_macro = True
+                if not in_new_macro:
+                    f.write(line)
+
+        run_black(filepath)
+
+    def find_last_macro(self, macros, meta_dir):
+        """
+        Given a list of macros, determine the after tag of the final macro in
+        the chain. Start from assuming the first before tag is the Version
+        Number.
+        Inputs:
+            - macros, a list of macro strings
+        Returns:
+            - str, the after tag of the final macro in the chain
+        """
+
+        after_tag = f"vn{self.version}"
+        while len(macros) > 0:
+            for macro in macros:
+                regexp = re.compile(rf"BEFORE_TAG\s*=\s*[\"']{after_tag}[\"']")
+                if regexp.search(macro):
+                    try:
+                        after_tag = re.search(
+                            rf"AFTER_TAG{TAG_REGEX}", macro
+                        ).group(1)
+                    except AttributeError:
+                        raise RuntimeError(
+                            "Couldn't find an after tag in the macro:\n"
+                            f"{macro}"
+                        )
+                    found_macro = macro
+                    macros.remove(found_macro)
+                    break
+            else:
+                raise RuntimeError(
+                    f"Couldn't find the before tag '{after_tag}' in macros in "
+                    f"the versions.py file at {meta_dir}"
+                )
+        return after_tag
+
+    def find_macro(self, meta_dir, macros):
+        """
+        Read through a list of macros, trying to find desired one. If this is
+        present then return true, otherwise false
+        Inputs:
+            - meta_dir, str, The path to the rose metadata directory containing
+              these macros
+            - macros, a list of macro strings
+        Returns:
+            - String containing the macro. Empty if the macro isn't found
+        """
+
+        version_file = os.path.join(meta_dir, "versions.py")
+
+        # Find the macro we're interested in
+        for macro in macros:
+            try:
+                macro_name = re.search(
+                    rf"class ({CLASS_NAME_REGEX})\(", macro
+                ).group(1)
+            except AttributeError as exc:
+                raise RuntimeError(
+                    "Unable to determine macro class name in "
+                    f"{version_file} in macro:\n{macro}"
+                ) from exc
+            # Parse the macro if this is the one we're interested in
+            if macro_name == self.class_name:
+                return macro
+        return ""
+
+    def get_full_import_path(self, imp):
+        """
+        Search through the Core, Jules and Apps working copies to get the full
+        path to a metadata directory
+        Inputs:
+            - imp, the import statement without the full path
+        Returns:
+            - the import statement containing the full path - default to using
+              the apps working copy
+        """
+
+        core_imp = os.path.join(self.core_source, imp)
+        if os.path.exists(core_imp):
+            return core_imp
+
+        jules_imp = os.path.join(self.jules_source, imp)
+        if os.path.exists(jules_imp):
+            return jules_imp
+
+        apps_imp = os.path.join(self.root_path, imp)
+        if os.path.exists(apps_imp):
+            return apps_imp
+
+        raise RuntimeError(
+            f"Couldn't find the import '{imp}' in any of the Apps, Core or "
+            "Jules sources."
+        )
+
+    def read_meta_imports(self, meta_dir, flag="import"):
+        """
+        Read a rose-meta.conf and record which other metadata files are imported
+        by this metadata.
+        Inputs:
+            - meta_dir, path to the rose metadata directory
+            - flag, either 'import' or 'meta'. Searches for lines in the config
+              file starting flag=. If 'meta', then will return the import
+              statement on that line
+        """
+
+        if flag == "import":
+            meta_file = os.path.join(meta_dir, "HEAD", "rose-meta.conf")
+        else:
+            meta_file = meta_dir
+
+        # First grep for lines starting with import=
+        # No imports if it doesn't return anything
+        result = run_command(f"grep -E '^ *{flag}=' {meta_file}", shell=True)
+        if not result.stdout:
+            if flag == "meta":
+                return ""
+            self.parsed_macros[meta_dir]["imports"] = []
+
+        imports = []
+        with open(meta_file, "r") as f:
+            in_import_list = False
+            for line in f:
+                line = line.strip()
+                if not line:
+                    # skip blank lines
+                    continue
+                if line.startswith(f"{flag}="):
+                    in_import_list = True
+                if in_import_list:
+                    if line.startswith("=") or line.startswith(f"{flag}="):
+                        # Split the import line by '=' then take the rhs
+                        # Then remove the trailing '/HEAD'
+                        # Then prepend the path to the working copy
+                        imp = line.split("=", 1)[1].strip("/HEAD")
+                        imp = self.get_full_import_path(imp)
+                        imports.append(imp)
+                        if flag == "meta":
+                            return imports[0]
+                    else:
+                        break
+        self.parsed_macros[meta_dir]["imports"] = imports
+
+    def read_python_imports(self, versions):
+        """
+        Read through a python versions.py file for any python module imports.
+        Record this in self.python_imports
+        Inputs:
+            - versions, list of lines in a versions.py file
+        """
+
+        started_imports = False
+        for line in versions:
+            line = line.strip()
+            if match_python_import(line):
+                started_imports = True
+                self.python_imports.add(line)
+            elif started_imports:
+                return
+
+    def write_python_imports(self, meta_dir):
+        """
+        Write out all required python module imports at the top of a versions.py
+        file. Read imports from self.python_imports
+        Inputs:
+            - meta_dir, path to the metadata directory with a versions.py file
+        """
+
+        fpath = os.path.join(meta_dir, "versions.py")
+
+        with open(fpath) as f:
+            versions_file = f.readlines()
+
+        started_imports = False
+        found_imports = set()
+        for i, line in enumerate(versions_file):
+            line = line.strip()
+            if match_python_import(line):
+                started_imports = True
+                found_imports.add(line)
+            elif started_imports:
+                insertion_index = i
+                break
+
+        missing_imports = self.python_imports.difference(found_imports)
+        for imp in missing_imports:
+            versions_file.insert(insertion_index, imp)
+
+        with open(fpath, "w") as f:
+            for line in versions_file:
+                f.write(line.strip("\n") + "\n")
+
+    def deduplicate_list(self, lst):
+        """
+        Remove duplicate items from a list, keeping the first
+        Need to preserve order so not using a set
+        Inputs:
+            - lst, the list to deduplicate
+        Returns:
+            - the deduplicated list
+        """
+        deduplicated = []
+        for item in lst:
+            if item not in deduplicated:
+                deduplicated.append(item)
+
+        return deduplicated
+
+    def determine_import_order(self, app):
+        """
+        Work out what order metadata is imported. This recursively works through
+        import statements recorded in self.parsed_macros["imports"]. Produces a
+        list of the order in which macro commands should be applied (this should
+        be the same order as the imports)
+        Inputs:
+            - app, the application or science section which we are trying to
+              find the import order for
+        Returns:
+            - A list of meta imports in the correct order
+        """
+
+        import_list = [app]
+        try:
+            imports = self.parsed_macros[app]["imports"]
+        except KeyError:
+            # Jules Shared directories will produce a key error - these are
+            # guaranteed to not import anything
+            imports = []
+        for meta_import in imports:
+            import_list = self.determine_import_order(meta_import) + import_list
+
+        return self.deduplicate_list(import_list)
+
+    def combine_macros(self, import_order):
+        """
+        For a given application, combine macro commands from imported metadata
+        and itself to get full macro for a particular change.
+        Inputs:
+            - version_file, the path to an applications versions.py file
+            - import_order, the metadata import order to match the order of
+              marcro commands.
+        Returns:
+            - string, combined macro commands
+        """
+
+        full_command = ""
+        for meta_import in import_order:
+            if (
+                meta_import in self.parsed_macros
+                and self.parsed_macros[meta_import]["commands"]
+            ):
+                # Add a comment labelling where these commands came from
+                full_command += (
+                    f"        # {self.parse_application_section(meta_import)}\n"
+                )
+                if self.parsed_macros[meta_import]["commands"].strip("\n"):
+                    full_command += (
+                        self.parsed_macros[meta_import]["commands"] + "\n"
+                    )
+                else:
+                    full_command += "        # Blank Upgrade Macro\n"
+        return full_command
+
+    def write_new_macro(self, meta_dir, full_command):
+        """
+        Write out the new macro with all relevant commands to the versions.py
+        file
+        Inputs:
+            - meta_dir, path to the metadata directory with a versions.py file
+            - full_command, str of the combined macro commands
+        """
+
+        parsed_macro = self.parsed_macros[meta_dir]
+        version_file = os.path.join(meta_dir, "versions.py")
+
+        with open(version_file, "a") as f:
+            f.write(
+                f"class {self.class_name}(MacroUpgrade):\n"
+                f'    """Upgrade macro for ticket {self.ticket_number} '
+                f'by {self.author}."""\n\n'
+                f'    BEFORE_TAG = "{parsed_macro["before_tag"]}"\n'
+                f'    AFTER_TAG = "{self.tag}"\n\n'
+                "    def upgrade(self, config, meta_config=None):\n"
+                f"{full_command}"  # this variable contains required whitespace
+                "        return config, self.reports\n"
+            )
+
+        run_black(version_file)
+
+    def preprocess_macros(self):
+        """
+        Overraching function to pre-process added macros
+        Run before running any rose macro upgrade commands"
+        Search through versions.py files for macros with the correct after-tag
+        Save info and then delete the macro when found
+        For each application combine required macros (those for the application
+        plus any from imported metadata).
+        Write this new macro to that applications versions.py file
+        """
+
+        # Get list of versions files to check - in both core and apps
+        self.find_meta_dirs(self.root_path)
+        self.find_meta_dirs(self.core_source)
+
+        for meta_dir in self.meta_dirs:
+            print(
+                "[INFO] Pre-processing macros in",
+                self.parse_application_section(meta_dir),
+            )
+            # Read an upgrade macro from a versions.py file, save the macro
+            # info and delete the macro from the file
+            parsed_versions = read_versions_file(meta_dir)
+            macros = split_macros(parsed_versions)
+            found_macro = self.find_macro(meta_dir, macros)
+            if not found_macro:
+                # If we reach here then the new macro hasn't been added to
+                # this versions file - in this case work out the final after
+                #  tag in the chain and record in parsed macros
+                last_after_tag = self.find_last_macro(macros, meta_dir)
+                self.parsed_macros[meta_dir] = {
+                    "before_tag": last_after_tag,
+                    "commands": "",
+                    "imports": "",
+                }
+            else:
+                self.parse_macro(found_macro, meta_dir)
+                # Remove the macro from the file
+                self.remove_macro(parsed_versions, meta_dir)
+
+            # Read through rose-meta files for import statements
+            # of other metadata
+            self.read_meta_imports(meta_dir)
+
+            # Read through the versions.py file for python import statements
+            self.read_python_imports(parsed_versions)
+
+        # Now reconstruct the macro for all applications which have the newly
+        # added macro or import metadata with the new macro
+        # Note, this is only done for applications, not for science sections
+        for meta_dir in self.meta_dirs:
+            if not (
+                meta_dir.startswith(
+                    os.path.join(self.root_path, "applications")
+                )
+                or meta_dir.startswith(
+                    os.path.join(self.core_source, "applications")
+                )
+            ):
+                continue
+            import_order = self.determine_import_order(meta_dir)
+            full_command = self.combine_macros(import_order)
+            # If there are commands to write out, do so and record this
+            # application as having the macro
+            if full_command:
+                print(
+                    "[INFO] Writing macros to",
+                    self.parse_application_section(meta_dir),
+                )
+                self.write_python_imports(meta_dir)
+                self.write_new_macro(meta_dir, full_command)
+                self.apps_with_macro.append(meta_dir)
+
+    ############################################################################
+    # Upgrade Apps Functions
+    ############################################################################
+
+    def metadata_check(self, meta_dir):
+        """ "
+        Note: Not currently run - see comment below
+        Run rose metadata-check on rose metadata directories to check the
+        validity of the metadata.
+        Inputs:
+            - meta_dir, path to a rose metadata directory
+        """
+
+        print(f"[INFO] Checking metadata in {meta_dir}")
+        command = f"rose metadata-check -C {os.path.join(meta_dir, 'HEAD')}"
+        result = run_command(command)
+        if result.returncode:
+            print(f"[FAIL] The metadata at {meta_dir} failed to validate.")
+            raise RuntimeError(
+                f"\nThe command run:\n{command}"
+                f"\nThe error message produced:\n{result.stderr}"
+            )
+        print(f"[PASS] {meta_dir} validated")
+
+    def apps_to_upgrade(self):
+        """
+        Loop over rose-stem apps, finding ones using metadata with an upgrade
+        macro.
+        Returns:
+            - list of paths to apps requiring upgrading
+        """
+        upgradeable_apps = []
+        app_dir_apps = os.path.join(self.root_path, "rose-stem", "app")
+        apps_lstdir = os.listdir(app_dir_apps)
+        app_dir_core = os.path.join(self.core_source, "rose-stem", "app")
+        core_lstdir = os.listdir(app_dir_core)
+        for app in apps_lstdir + core_lstdir:
+            if "fcm_make" in app or "lfric_coupled_rivers" in app:
+                continue
+            if app in apps_lstdir:
+                app_path = os.path.join(app_dir_apps, app)
+            else:
+                app_path = os.path.join(app_dir_core, app)
+            if not os.path.isdir(app_path):
+                continue
+            meta_import = self.read_meta_imports(
+                os.path.join(app_path, "rose-app.conf"), "meta"
+            )
+            meta_import = os.path.dirname(meta_import)
+            if meta_import in self.apps_with_macro:
+                upgradeable_apps.append((app, app_path))
+
+        return upgradeable_apps
+
+    def run_app_upgrade(self, app, app_path):
+        """
+        Run 'rose app-upgrade' on a particular rose-stem app
+        Inputs:
+            - app, the name of the app being upgraded
+            - app_path, the path to this app
+        """
+
+        print(f"[INFO] Upgrading the rose-stem app {app}")
+        command = f"rose app-upgrade -a -y -C {app_path} {self.tag}"
+        result = run_command(command)
+        if result.returncode:
+            print(f"[FAIL] The rose-stem app {app} failed to upgrade")
+            raise RuntimeError(
+                f"\nThe command run:\n{command}"
+                f"\nThe error message produced:\n{result.stderr}"
+            )
+        print(f"[PASS] Upgraded rose-stem app {app} successfully")
+
+    def run_macro_fix(self, app, app_path):
+        """
+        Run 'rose macro --fix' on a particular rose-stem app to force metadata
+        consistency
+        Inputs:
+            - app, the name of the app being upgraded
+            - app_path, the path to this app
+        """
+        print(f"[INFO] Forcing metadata consistency in app {app}")
+        command = f"rose macro --fix -y -C {app_path}"
+        result = run_command(command)
+        if result.returncode:
+            print(f"[FAIL] Unable to force metadata consistency in {app}")
+            raise RuntimeError(
+                f"\nThe command run:\n{command}"
+                f"\nThe error message produced:\n{result.stderr}"
+            )
+        print(f"[PASS] Successfully forced metadata consistency in {app}")
+
+    def upgrade_apps(self):
+        """
+        Overarching function to run rose commands to apply upgrade macros to
+        rose-stem apps.
+        First run over all metadata directories and run rose metadata-check on
+        each
+        Then run over all rose apps. If there is an import statement for an
+        application with the upgrade macro (stored in self.apps_with_macro) then
+        run rose commands on it.
+        - rose app-upgrade
+        - rose macro --fix
+        """
+
+        # This step would be good to do (as we do in the UM). However, not all
+        # metadata files validate currently as they use gungho namelists but are
+        # imported by gungho (eg. um_physics_interface). The remainder are
+        # tested regularly by the lfric_apps validate_rose_meta script, so happy
+        # to not do this here. Leaving the code, so that we do validate these
+        # once the metadata structure has been improved.
+        # banner_print("[INFO] Validating Metadata Config Files")
+        # for meta_dir in self.meta_dirs:
+        #     self.metadata_check(meta_dir)
+
+        banner_print("[INFO] Upgrading Apps")
+        upgradeable_apps = self.apps_to_upgrade()
+        for app, app_path in upgradeable_apps:
+            self.run_app_upgrade(app, app_path)
+            self.run_macro_fix(app, app_path)
+            if app_path.startswith(self.core_source):
+                self.upgraded_core = True
+
+
+def parse_args():
+    """
+    Read command line args
+    """
+
+    parser = argparse.ArgumentParser(
+        "Pre-process and apply lfric_apps upgrade macros."
+    )
+    parser.add_argument(
+        "tag",
+        metavar="after-tag",
+        help="The After Tag of the upgrade macro being upgraded to.",
+    )
+    parser.add_argument(
+        "-a",
+        "--apps",
+        default=".",
+        help="The path to the LFRic Apps working copy being used. Defaults to  "
+        "the location the script is being run from - this assumes you are in a "
+        "working copy.",
+    )
+    parser.add_argument(
+        "-c",
+        "--core",
+        default=None,
+        help="The LFRic Core source being used."
+        "Either a path to a working copy or an FCM URL."
+        "If not set, will be read from the dependencies.sh",
+    )
+    parser.add_argument(
+        "-j",
+        "--jules",
+        default=None,
+        help="The Jules source being used."
+        "Either a path to a working copy or an FCM URL."
+        "If not set, will be read from the dependencies.sh",
+    )
+    return parser.parse_args()
+
+
+def main():
+    """
+    Main function for this program
+    """
+
+    args = parse_args()
+
+    # if the class name doesn't conform to the expected vnXX.Y_tTTTT naming
+    # convention raise an error
+    class_name = args.tag.replace(".", "")
+    if not re.match(CLASS_NAME_REGEX, class_name):
+        raise RuntimeError(
+            f"The class name '{class_name}' does not conform to the "
+            "'vnXX.Y_tTTTT' naming scheme. Please modify and rerun."
+        )
+
+    macro_object = ApplyMacros(args.tag, args.apps, args.core, args.jules)
+
+    # Pre-process macros
+    banner_print("Pre-Processing Macros")
+    macro_object.preprocess_macros()
+
+    # Upgrade Rose Stem Apps
+    macro_object.upgrade_apps()
+
+    # Clean up temporary directories
+    for repo, directory in macro_object.temp_dirs.items():
+        if macro_object.upgraded_core and repo == "lfric_core":
+            banner_print("WARNING")
+            print(
+                "Macros have been applied to apps in LFRic Core. A temporary "
+                "copy of the LFRic Core source given by the `dependencies.sh` "
+                f"file is located at:\n{macro_object.core_source}\nEnsure you "
+                "have committed those changes back to the core branch."
+            )
+            continue
+        shutil.rmtree(directory)
+
+    # Run rose config-dump on rose-stem
+    config_dump_apps = (
+        f"rose config-dump {os.path.join(macro_object.root_path), 'rose-stem'}"
+    )
+    run_command(config_dump_apps)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/lfric_macros/tests/__init__.py b/lfric_macros/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/lfric_macros/tests/test_apply_macros.py b/lfric_macros/tests/test_apply_macros.py
new file mode 100644
index 0000000..b92449a
--- /dev/null
+++ b/lfric_macros/tests/test_apply_macros.py
@@ -0,0 +1,184 @@
+import pytest
+import subprocess
+import shutil
+from ..apply_macros import *
+
+# A macro that we want to find for these tests
+desired_macro = """class vn00_t001(MacroUpgrade):
+    # Upgrade macro for ticket #001 by <Test Author>.
+    BEFORE_TAG = "vn0.0_t000"
+    AFTER_TAG = "vn0.0_t001"
+    def upgrade(self, config, meta_config=None):
+        # Input your macro commands here
+        self.add_setting(
+            config, ["namelist:namelist1", "opt1"], "value1"
+        )
+        return config, self.reports"""
+
+
+# A macro pre-existing in the file, forming part of the chain
+existing_macro = """class vn00_t000(MacroUpgrade):
+    # Upgrade macro for ticket #000 by <Test Author>.
+    BEFORE_TAG = "vn0.0"
+    AFTER_TAG = "vn0.0_t000"
+    def upgrade(self, config, meta_config=None):
+        # Input your macro commands here
+        self.add_setting(
+            config, ["namelist:namelist0", "opt0"], "value0"
+        )
+        return config, self.reports"""
+
+
+# test_versions_file is a string representing an imaginary versions.py file to
+# unit test functions from. This is the parsed version so contains no blank line
+test_versions_file = """import sys
+from metomi.rose.upgrade import MacroUpgrade
+class UpgradeError(Exception):
+    def __init__(self, msg):
+        self.msg = msg
+    def __repr__(self):
+        sys.tracebacklimit = 0
+        return self.msg
+    __str__ = __repr__"""
+test_versions_file += f"\n{desired_macro}\n{existing_macro}"
+test_versions_file = [f"{x}\n" for x in test_versions_file.split("\n")]
+
+# The expected result from split_macros for the versions
+expected_split_macros = [
+    desired_macro,
+    existing_macro
+]
+
+# ApplyMacros below requires an LFRic Apps working copy to work - check out the
+# head of the lfric_apps trunk for this purpose. The actual contents of the
+# working copy are not important for the purposes of the unit tests
+appsdir = "/tmp/persistent/tmpapps"#tempfile.mkdtemp()
+result = subprocess.run(
+    f"fcm co fcm:lfric_apps.x_tr {appsdir}".split(),
+    check=False,
+    capture_output=True,
+    text=True,
+    timeout=120
+)
+if result.returncode:
+    raise RuntimeError(
+        "Failed to checkout required LFRic Apps Working Copy with error ",
+        result.stderr
+    )
+
+# Create an instance of the apply_macros class
+# Pass a known directory in as the Jules and Core sources as these are not
+# required for testing
+am = ApplyMacros(
+    "vn0.0_t001",
+    appsdir,
+    "/tmp",
+    "/tmp"
+)
+
+def test_split_macros():
+    m = split_macros(test_versions_file)
+    # Remove trailing newlines as these are unimportant
+    for i, item in enumerate(m):
+        m[i] = item.strip("\n")
+    assert m == expected_split_macros
+
+
+def test_find_macro():
+    assert am.find_macro("meta_dir", expected_split_macros) == desired_macro
+    assert am.find_macro("meta_dir", [existing_macro]) == ""
+    expected_error = r".*meta_dir/versions.py.*"
+    with pytest.raises(RuntimeError, match=expected_error):
+        am.find_macro("meta_dir", [""])
+
+
+def test_find_last_macro():
+    assert am.find_last_macro(expected_split_macros, "meta_dir") == "vn0.0_t001"
+
+
+def test_parse_macro():
+    am.parse_macro(desired_macro, "meta_dir")
+    expected_dict = {
+        "before_tag": "vn0.0_t000",
+        "commands": """        self.add_setting(
+            config, ["namelist:namelist1", "opt1"], "value1"
+        )
+"""
+    }
+    assert am.parsed_macros["meta_dir"] == expected_dict
+    assert am.ticket_number == "#001"
+    assert am.author == "Test Author"
+    with pytest.raises(RuntimeError, match=r".*failed/versions.py"):
+        am.parse_macro("", "failed")
+
+
+def test_read_meta_imports():
+    am.parsed_macros["tests/test_meta_dir"] = {}
+    am.read_meta_imports("tests/test_meta_dir")
+    expected_imports = [
+        os.path.join(am.root_path, "science", "gungho"),
+        os.path.join(am.root_path, "applications", "lfric_atm")
+    ]
+    assert am.parsed_macros["tests/test_meta_dir"]["imports"] == expected_imports
+    expected_meta = os.path.join(am.root_path, "applications", "lfric_atm")
+    assert am.read_meta_imports("tests/test_meta_dir/rose-app.conf", "meta") == expected_meta
+
+
+def test_determine_import_order():
+    am.parsed_macros["import1"] = {}
+    am.parsed_macros["import2"] = {}
+    am.parsed_macros["import3"] = {}
+    am.parsed_macros["import4"] = {}
+    am.parsed_macros["import1"]["imports"] = ["import3", "import2"]
+    am.parsed_macros["import3"]["imports"] = ["import4"]
+    am.parsed_macros["import4"]["imports"] = []
+    am.parsed_macros["import2"]["imports"] = []
+    expected_order = [
+        "import2",
+        "import4",
+        "import3",
+        "import1"
+    ]
+    assert am.determine_import_order("import1") == expected_order
+
+
+def test_combine_macros():
+    am.parsed_macros["importA"] = {
+        "commands": "        importA command"
+    }
+    am.parsed_macros["importB"] = {
+        "commands": "        importB command"
+    }
+    expected_combined = (
+        "        # importA\n        importA command\n"
+        "        # importB\n        importB command\n"
+    )
+    assert am.combine_macros(["importA", "importB"]) == expected_combined
+
+
+def test_parse_application_section():
+    assert am.parse_application_section("meta_dir/HEAD") == "meta_dir"
+    assert am.parse_application_section("meta_dir/versions.py") == "meta_dir"
+    assert am.parse_application_section(f"{am.root_path}/meta_dir") == "meta_dir"
+    assert am.parse_application_section(f"{am.core_source}/meta_dir") == "meta_dir"
+    assert am.parse_application_section(f"{am.jules_source}/meta_dir") == "meta_dir"
+
+
+def test_deduplicate_list():
+    assert am.deduplicate_list([1,2,3]) == [1,2,3]
+    assert am.deduplicate_list([1,2,2,3,3,3,]) == [1,2,3]
+    assert am.deduplicate_list([1,2,1,3,2]) == [1,2,3]
+
+
+def test_match_python_imports():
+    assert match_python_import("import z") == True
+    assert match_python_import("from x import y") == True
+    assert match_python_import("from a import b.c") == True
+    assert match_python_import("import m as n") == True
+    assert match_python_import("false") == False
+
+# Remove appsdir
+@pytest.fixture(scope='session', autouse=True)
+def remove_tempdir():
+    yield
+    shutil.rmtree(appsdir)
diff --git a/lfric_macros/tests/test_meta_dir/HEAD/rose-meta.conf b/lfric_macros/tests/test_meta_dir/HEAD/rose-meta.conf
new file mode 100644
index 0000000..16b4357
--- /dev/null
+++ b/lfric_macros/tests/test_meta_dir/HEAD/rose-meta.conf
@@ -0,0 +1,4 @@
+import=science/gungho
+      =applications/lfric_atm
+
+[metadata]
diff --git a/lfric_macros/tests/test_meta_dir/rose-app.conf b/lfric_macros/tests/test_meta_dir/rose-app.conf
new file mode 100644
index 0000000..4aa90c5
--- /dev/null
+++ b/lfric_macros/tests/test_meta_dir/rose-app.conf
@@ -0,0 +1,3 @@
+meta=applications/lfric_atm
+
+[metadata]