diff --git a/changelog.d/20230427_165520_regis_build_mount.md b/changelog.d/20230427_165520_regis_build_mount.md
index fb29b8c..36fc658 100644
--- a/changelog.d/20230427_165520_regis_build_mount.md
+++ b/changelog.d/20230427_165520_regis_build_mount.md
@@ -1 +1,3 @@
 - [Improvement] Automatically pull Docker image cache from the remote registry. Again, this will considerably improve image build-time, particularly in "cold-start" scenarios, where the images need to be built from scratch. The registry cache can be disabled with the `tutor images build --no-registry-cache` option. (by @regisb)
+- [Feature] Automatically mount host folders *at build time*. This is a really important feature, as it allows us to transparently build images using local forks of remote repositories. (by @regisb)
+- 💥[Deprecation] Remove the various `--mount` options. These options are replaced by persistent mounts. (by @regisb)
diff --git a/docs/dev.rst b/docs/dev.rst
index 5ee10c0..684d806 100644
--- a/docs/dev.rst
+++ b/docs/dev.rst
@@ -12,31 +12,25 @@ First-time setup
 
 Firstly, either :ref:`install Tutor <install>` (for development against the named releases of Open edX) or :ref:`install Tutor Nightly <nightly>` (for development against Open edX's master branches).
 
+Then, optionally, tell Tutor to use a local fork of edx-platform. In that case you will need to rebuild the "openedx" Docker image::
+
+    tutor config save --append MOUNTS=./edx-platform
+    tutor images build openedx
+
 Then, run one of the following in order to launch the developer platform setup process::
 
     # To use the edx-platform repository that is built into the image, run:
     tutor dev launch
 
-    # To bind-mount and run a local clone of edx-platform, replace
-    # './edx-platform' with the path to the local clone and run:
-    tutor dev launch --mount=./edx-platform
-
 This will perform several tasks. It will:
 
 * stop any existing locally-running Tutor containers,
-
 * disable HTTPS,
-
 * set ``LMS_HOST`` to `local.overhang.io <http://local.overhang.io>`_ (a convenience domain that simply `points at 127.0.0.1 <https://dnschecker.org/#A/local.overhang.io>`_),
-
 * prompt for a platform details (with suitable defaults),
-
 * build an ``openedx-dev`` image, which is based ``openedx`` production image but is `specialized for developer usage`_,
-
 * start LMS, CMS, supporting services, and any plugged-in services,
-
 * ensure databases are created and migrated, and
-
 * run service initialization scripts, such as service user creation and Waffle configuration.
 
 Additionally, when a local clone of edx-platform is bind-mounted, it will:
@@ -55,10 +49,13 @@ Now, use the ``tutor dev ...`` command-line interface to manage the development
 
 .. note::
 
-  Wherever the ``[--mount=./edx-platform]`` option is present, either:
+  If you've added your edx-platform to the ``MOUNTS`` setting, you can remove at any time by running::
 
-  * omit it when running of the edx-platform repository built into the image, or
-  * substitute it with ``--mount=<path/to/edx-platform>``.
+    tutor config save --remove MOUNTS=./edx-platform
+
+  At any time, check your configuration by running::
+
+    tutor config printvalue MOUNTS
 
   Read more about bind-mounts :ref:`below <bind_mounts>`.
 
@@ -74,17 +71,17 @@ Starting the platform back up
 
 Once first-time setup has been performed with ``launch``, the platform can be started going forward with the lighter-weight ``start -d`` command, which brings up containers *detached* (that is: in the background), but does not perform any initialization tasks::
 
-  tutor dev start -d [--mount=./edx-platform]
+  tutor dev start -d
 
 Or, to start with platform with containers *attached* (that is: in the foreground, the current terminal), omit the ``-d`` flag::
 
-  tutor dev start [--mount=./edx-platform]
+  tutor dev start
 
 When running containers attached, stop the platform with ``Ctrl+c``, or switch to detached mode using ``Ctrl+z``.
 
 Finally, the platform can also be started back up with ``launch``. It will take longer than ``start``, but it will ensure that config is applied, databases are provisioned & migrated, plugins are fully initialized, and (if applicable) the bind-mounted edx-platform is set up. Notably, ``launch`` is idempotent, so it is always safe to run it again without risk to data. Including the ``--pullimages`` flag will also ensure that container images are up-to-date::
 
-  tutor dev launch [--mount=./edx-platform] --pullimages
+  tutor dev launch --pullimages
 
 Debugging with breakpoints
 --------------------------
@@ -92,32 +89,32 @@ Debugging with breakpoints
 To debug a local edx-platform repository, add a `python breakpoint <https://docs.python.org/3/library/functions.html#breakpoint>`__ with ``breakpoint()`` anywhere in the code. Then, attach to the applicable service's container by running ``start`` (without ``-d``) followed by the service's name::
 
   # Debugging LMS:
-  tutor dev start [--mount=./edx-platform] lms
+  tutor dev start lms
 
   # Or, debugging CMS:
-  tutor dev start [--mount=./edx-platform] cms
+  tutor dev start cms
 
 Running arbitrary commands
 --------------------------
 
 To run any command inside one of the containers, run ``tutor dev run [OPTIONS] SERVICE [COMMAND] [ARGS]...``. For instance, to open a bash shell in the LMS or CMS containers::
 
-    tutor dev run [--mount=./edx-platform] lms bash
-    tutor dev run [--mount=./edx-platform] cms bash
+    tutor dev run lms bash
+    tutor dev run cms bash
 
 To open a python shell in the LMS or CMS, run::
 
-    tutor dev run [--mount=./edx-platform] lms ./manage.py lms shell
-    tutor dev run [--mount=./edx-platform] cms ./manage.py cms shell
+    tutor dev run lms ./manage.py lms shell
+    tutor dev run cms ./manage.py cms shell
 
 You can then import edx-platform and django modules and execute python code.
 
 To rebuild assets, you can use the ``openedx-assets`` command that ships with Tutor::
 
-    tutor dev run [--mount=./edx-platform] lms openedx-assets build --env=dev
+    tutor dev run lms openedx-assets build --env=dev
 
 
-.. _specialized for developer usage: 
+.. _specialized for developer usage:
 
 Rebuilding the openedx-dev image
 --------------------------------
@@ -143,35 +140,42 @@ Sharing directories with containers
 
 It may sometimes be convenient to mount container directories on the host, for instance: for editing and debugging. Tutor provides different solutions to this problem.
 
-.. _mount_option:
+.. _persistent_mounts:
 
-Bind-mount volumes with ``--mount``
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Persistent bind-mounted volumes with ``MOUNTS``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The ``launch``, ``run``, ``init`` and ``start`` subcommands of ``tutor dev`` and ``tutor local`` support the ``-m/--mount`` option (see :option:`tutor dev start -m`) which can take two different forms. The first is explicit::
+``MOUNTS`` is a Tutor setting to bind-mount host directories both at build time and run time:
 
-    tutor dev start --mount=lms:/path/to/edx-platform:/openedx/edx-platform lms
+- At build time: plugins can automatically add certain directories listed in this setting to the `Docker build context <https://docs.docker.com/engine/reference/commandline/buildx_build/#build-context>`__. This makes it possible to transparently build a Docker image using a locally checked-out repository.
+- At run time: host directories will be bind-mounted in running containers, using either an automatic or a manual configuration.
 
-And the second is implicit::
+After some values have been added to the ``MOUNTS`` setting, all ``tutor dev`` and ``tutor local`` commands will make use of these bind-mount volumes.
 
-    tutor dev start --mount=/path/to/edx-platform lms
+Values added to ``MOUNTS`` can take one of two forms. The first is explicit::
 
-With the explicit form, the ``--mount`` option means "bind-mount the host folder /path/to/edx-platform to /openedx/edx-platform in the lms container".
+    tutor config save --append MOUNTS=lms:/path/to/edx-platform:/openedx/edx-platform
 
-If you use the explicit format, you will quickly realise that you usually want to bind-mount folders in multiple containers at a time. For instance, you will want to bind-mount the edx-platform repository in the "cms" container. To do that, write instead::
+The second is implicit::
 
-    tutor dev start --mount=lms,cms:/path/to/edx-platform:/openedx/edx-platform lms
+    tutor config save --append MOUNTS=/path/to/edx-platform
 
-This command line can become cumbersome and inconvenient to work with. But Tutor can be smart about bind-mounting folders to the right containers in the right place when you use the implicit form of the ``--mount`` option. For instance, the following commands are equivalent::
+With the explicit form, the setting means "bind-mount the host folder /path/to/edx-platform to /openedx/edx-platform in the lms container at run time".
 
-    # Explicit form
-    tutor dev start --mount=lms,lms-worker,lms-job,cms,cms-worker,cms-job:/path/to/edx-platform:/openedx/edx-platform lms
-    # Implicit form
-    tutor dev start --mount=/path/to/edx-platform lms
+If you use the explicit format, you will quickly realise that you usually want to bind-mount folders in multiple containers at a time. For instance, you will want to bind-mount the edx-platform repository in the "cms" container, but also the "lms-worker" and "cms-worker" containers. To do that, write instead::
 
-So, when should you *not* be using the implicit form? That would be when Tutor does not know where to bind-mount your host folders. For instance, if you wanted to bind-mount your edx-platform virtual environment located in ``~/venvs/edx-platform``, you should not write ``--mount=~/venvs/edx-platform``, because that folder would be mounted in a way that would override the edx-platform repository in the container. Instead, you should write::
+    # each service is added to a coma-separated list
+    tutor config save --append MOUNTS=lms,cms,lms-worker,cms-worker:/path/to/edx-platform:/openedx/edx-platform
 
-    tutor dev start --mount=lms:~/venvs/edx-platform:/openedx/venv lms
+This command line is a bit cumbersome. In addition, with this explicit form, the edx-platform repository will *not* be added to the build context at build time. But Tutor can be smart about bind-mounting folders to the right containers in the right place when you use the implicit form of the ``MOUNTS`` setting. For instance, the following implicit form can be used instead of the explicit form above::
+
+    tutor config save --append MOUNTS=/path/to/edx-platform
+
+With this implicit form, the edx-platform repo will be bind-mounted in the containers at run time, just like with the explicit form. But in addition, the edx-platform will also automatically be added to the Docker image at build time.
+
+So, when should you *not* be using the implicit form? That would be when Tutor does not know where to bind-mount your host folders. For instance, if you wanted to bind-mount your edx-platform virtual environment located in ``~/venvs/edx-platform``, you should not write ``--append MOUNTS=~/venvs/edx-platform``, because that folder would be mounted in a way that would override the edx-platform repository in the container. Instead, you should write::
+
+    tutor config save --append MOUNTS=lms:~/venvs/edx-platform:/openedx/venv
 
 .. note:: Remember to setup your edx-platform repository for development! See :ref:`edx_platform_dev_env`.
 
@@ -182,16 +186,16 @@ Sometimes, you may want to modify some of the files inside a container for which
 
     tutor dev copyfrom lms /openedx/venv ~
 
-Then, bind-mount that folder back in the container with the ``--mount`` option (described :ref:`above <mount_option>`)::
+Then, bind-mount that folder back in the container with the ``MOUNTS`` setting (described :ref:`above <persistent_mounts>`)::
 
-    tutor dev start --mount lms:~/venv:/openedx/venv lms
+    tutor config save --append MOUNTS=lms:~/venv:/openedx/venv
 
-You can then edit the files in ``~/venv`` on your local filesystem and see the changes live in your container.
+You can then edit the files in ``~/venv`` on your local filesystem and see the changes live in your "lms" container.
 
 Manual bind-mount to any directory
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-.. warning:: Manually bind-mounting volumes with the ``--volume`` option makes it difficult to simultaneously bind-mount to multiple containers. Also, the ``--volume`` options are not compatible with ``start`` commands. For an alternative, see the :ref:`mount option <mount_option>`.
+.. warning:: Manually bind-mounting volumes with the ``--volume`` option makes it difficult to simultaneously bind-mount to multiple containers. Also, the ``--volume`` options are not compatible with ``start`` commands. For an alternative, see the :ref:`persistent mounts <persistent_mounts>`.
 
 The above solution may not work for you if you already have an existing directory, outside of the "volumes/" directory, which you would like mounted in one of your containers. For instance, you may want to mount your copy of the `edx-platform <https://github.com/openedx/edx-platform/>`__ repository. In such cases, you can simply use the ``-v/--volume`` `Docker option <https://docs.docker.com/storage/volumes/#choose-the--v-or---mount-flag>`__::
 
@@ -200,7 +204,7 @@ The above solution may not work for you if you already have an existing director
 Override docker-compose volumes
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The above solutions require that you explicitly pass the ``-m/--mount`` options to every ``run``, ``start`` or ``init`` command, which may be inconvenient. To address these issues, you can create a ``docker-compose.override.yml`` file that will specify custom volumes to be used with all ``dev`` commands::
+Adding items to the ``MOUNTS`` setting effectively adds new bind-mount volumes to the ``docker-compose.yml`` files. But you might want to have more control over your volumes, such as adding read-only options, or customising other fields of the different services. To address these issues, you can create a ``docker-compose.override.yml`` file that will specify custom volumes to be used with all ``dev`` commands::
 
     vim "$(tutor config printroot)/env/dev/docker-compose.override.yml"
 
@@ -221,7 +225,7 @@ You are then free to bind-mount any directory to any container. For instance, to
         volumes:
           - /path/to/edx-platform:/openedx/edx-platform
 
-This override file will be loaded when running any ``tutor dev ..`` command. The edx-platform repo mounted at the specified path will be automatically mounted inside all LMS and CMS containers. With this file, you should no longer specify the ``-m/--mount`` option from the command line.
+This override file will be loaded when running any ``tutor dev ..`` command. The edx-platform repo mounted at the specified path will be automatically mounted inside all LMS and CMS containers.
 
 .. note::
     The ``tutor local`` commands load the ``docker-compose.override.yml`` file from the ``$(tutor config printroot)/env/local/docker-compose.override.yml`` directory. One-time jobs from initialisation commands load the ``local/docker-compose.jobs.override.yml`` and ``dev/docker-compose.jobs.override.yml``.
diff --git a/docs/tutorials/arm64.rst b/docs/tutorials/arm64.rst
index 0ddc177..63c8a92 100644
--- a/docs/tutorials/arm64.rst
+++ b/docs/tutorials/arm64.rst
@@ -27,6 +27,7 @@ Then, build the "openedx" and "permissions" images::
     tutor images build openedx permissions
 
 .. TODO we don't want this instruction anymore
+
 If you want to use Tutor as an Open edX development environment, you should also build the development images::
     tutor dev dc build lms
 
diff --git a/tests/commands/test_compose.py b/tests/commands/test_compose.py
deleted file mode 100644
index 9cccfb9..0000000
--- a/tests/commands/test_compose.py
+++ /dev/null
@@ -1,88 +0,0 @@
-from __future__ import annotations
-
-import typing as t
-import unittest
-from io import StringIO
-from unittest.mock import patch
-
-from click.exceptions import ClickException
-
-from tutor import hooks
-from tutor.commands import compose
-from tutor.commands.local import LocalContext
-
-
-class ComposeTests(unittest.TestCase):
-    maxDiff = None  # Ensure we can see long diffs of YAML files.
-
-    def test_mount_option_parsing(self) -> None:
-        param = compose.MountParam()
-
-        self.assertEqual(
-            [("lms", "/path/to/edx-platform", "/openedx/edx-platform")],
-            param("lms:/path/to/edx-platform:/openedx/edx-platform"),
-        )
-        self.assertEqual(
-            [
-                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
-                ("cms", "/path/to/edx-platform", "/openedx/edx-platform"),
-            ],
-            param("lms,cms:/path/to/edx-platform:/openedx/edx-platform"),
-        )
-        self.assertEqual(
-            [
-                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
-                ("cms", "/path/to/edx-platform", "/openedx/edx-platform"),
-            ],
-            param("lms, cms:/path/to/edx-platform:/openedx/edx-platform"),
-        )
-        self.assertEqual(
-            [
-                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
-                ("lms-worker", "/path/to/edx-platform", "/openedx/edx-platform"),
-            ],
-            param("lms,lms-worker:/path/to/edx-platform:/openedx/edx-platform"),
-        )
-        with self.assertRaises(ClickException):
-            param("lms,:/path/to/edx-platform:/openedx/edx-platform")
-
-    @patch("sys.stdout", new_callable=StringIO)
-    def test_compose_local_tmp_generation(self, _mock_stdout: StringIO) -> None:
-        """
-        Ensure that docker-compose.tmp.yml is correctly generated.
-        """
-        param = compose.MountParam()
-        mount_args = (
-            # Auto-mounting of edx-platform to lms* and cms*
-            param.convert_implicit_form("/path/to/edx-platform"),
-            # Manual mounting of some other folder to mfe and lms
-            param.convert_explicit_form(
-                "mfe,lms:/path/to/something-else:/openedx/something-else"
-            ),
-        )
-        # Mount volumes
-        compose.mount_tmp_volumes(mount_args, LocalContext(""))
-
-        compose_file: dict[str, t.Any] = hooks.Filters.COMPOSE_LOCAL_TMP.apply({})
-        actual_services: dict[str, t.Any] = compose_file["services"]
-        expected_services: dict[str, t.Any] = {
-            "cms": {"volumes": ["/path/to/edx-platform:/openedx/edx-platform"]},
-            "cms-worker": {"volumes": ["/path/to/edx-platform:/openedx/edx-platform"]},
-            "lms": {
-                "volumes": [
-                    "/path/to/edx-platform:/openedx/edx-platform",
-                    "/path/to/something-else:/openedx/something-else",
-                ]
-            },
-            "lms-worker": {"volumes": ["/path/to/edx-platform:/openedx/edx-platform"]},
-            "mfe": {"volumes": ["/path/to/something-else:/openedx/something-else"]},
-        }
-        self.assertEqual(actual_services, expected_services)
-
-        compose_jobs_file = hooks.Filters.COMPOSE_LOCAL_JOBS_TMP.apply({})
-        actual_jobs_services = compose_jobs_file["services"]
-        expected_jobs_services: dict[str, t.Any] = {
-            "cms-job": {"volumes": ["/path/to/edx-platform:/openedx/edx-platform"]},
-            "lms-job": {"volumes": ["/path/to/edx-platform:/openedx/edx-platform"]},
-        }
-        self.assertEqual(actual_jobs_services, expected_jobs_services)
diff --git a/tests/commands/test_images.py b/tests/commands/test_images.py
index 622be9b..f3e0132 100644
--- a/tests/commands/test_images.py
+++ b/tests/commands/test_images.py
@@ -149,7 +149,7 @@ class ImagesTests(PluginsTestCase, TestCommandMixin):
                 "docker_args",
                 "--cache-from=type=registry,ref=service1:1.0.0-cache",
             ],
-            list(image_build.call_args[0][1:])
+            list(image_build.call_args[0][1:]),
         )
 
     def test_images_push(self) -> None:
diff --git a/tests/test_bindmount.py b/tests/test_bindmount.py
new file mode 100644
index 0000000..4e656a1
--- /dev/null
+++ b/tests/test_bindmount.py
@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+import unittest
+
+from tutor import bindmount
+
+
+class BindmountTests(unittest.TestCase):
+    def test_parse_explicit(self) -> None:
+        self.assertEqual(
+            [("lms", "/path/to/edx-platform", "/openedx/edx-platform")],
+            bindmount.parse_explicit_mount(
+                "lms:/path/to/edx-platform:/openedx/edx-platform"
+            ),
+        )
+        self.assertEqual(
+            [
+                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("cms", "/path/to/edx-platform", "/openedx/edx-platform"),
+            ],
+            bindmount.parse_explicit_mount(
+                "lms,cms:/path/to/edx-platform:/openedx/edx-platform"
+            ),
+        )
+        self.assertEqual(
+            [
+                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("cms", "/path/to/edx-platform", "/openedx/edx-platform"),
+            ],
+            bindmount.parse_explicit_mount(
+                "lms, cms:/path/to/edx-platform:/openedx/edx-platform"
+            ),
+        )
+        self.assertEqual(
+            [
+                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("lms-worker", "/path/to/edx-platform", "/openedx/edx-platform"),
+            ],
+            bindmount.parse_explicit_mount(
+                "lms,lms-worker:/path/to/edx-platform:/openedx/edx-platform"
+            ),
+        )
+        self.assertEqual(
+            [("lms", "/path/to/edx-platform", "/openedx/edx-platform")],
+            bindmount.parse_explicit_mount(
+                "lms,:/path/to/edx-platform:/openedx/edx-platform"
+            ),
+        )
+
+    def test_parse_implicit(self) -> None:
+        # Import module to make sure filter is created
+        # pylint: disable=import-outside-toplevel,unused-import
+        import tutor.commands.compose
+
+        self.assertEqual(
+            [
+                ("lms", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("cms", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("lms-worker", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("cms-worker", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("lms-job", "/path/to/edx-platform", "/openedx/edx-platform"),
+                ("cms-job", "/path/to/edx-platform", "/openedx/edx-platform"),
+            ],
+            bindmount.parse_implicit_mount("/path/to/edx-platform"),
+        )
diff --git a/tutor/bindmount.py b/tutor/bindmount.py
new file mode 100644
index 0000000..0f2d206
--- /dev/null
+++ b/tutor/bindmount.py
@@ -0,0 +1,71 @@
+from __future__ import annotations
+
+from functools import lru_cache
+import os
+import re
+import typing as t
+
+from tutor import hooks
+
+
+def iter_mounts(user_mounts: list[str], name: str) -> t.Iterable[str]:
+    """
+    Iterate on the bind-mounts that are available to any given compose service. The list
+    of bind-mounts is parsed from `user_mounts` and we yield only those for service
+    `name`.
+
+    Calling this function multiple times makes repeated calls to the parsing functions,
+    but that's OK because their result is cached.
+    """
+    for user_mount in user_mounts:
+        for service, host_path, container_path in parse_mount(user_mount):
+            if service == name:
+                yield f"{host_path}:{container_path}"
+
+
+def parse_mount(value: str) -> list[tuple[str, str, str]]:
+    """
+    Parser for mount arguments of the form "service1[,service2,...]:/host/path:/container/path".
+
+    Returns a list of (service, host_path, container_path) tuples.
+    """
+    mounts = parse_explicit_mount(value) or parse_implicit_mount(value)
+    return mounts
+
+
+@lru_cache(maxsize=None)
+def parse_explicit_mount(value: str) -> list[tuple[str, str, str]]:
+    """
+    Argument is of the form "containers:/host/path:/container/path".
+    """
+    # Note that this syntax does not allow us to include colon ':' characters in paths
+    match = re.match(
+        r"(?P<services>[a-zA-Z0-9-_, ]+):(?P<host_path>[^:]+):(?P<container_path>[^:]+)",
+        value,
+    )
+    if not match:
+        return []
+
+    mounts: list[tuple[str, str, str]] = []
+    services: list[str] = [service.strip() for service in match["services"].split(",")]
+    host_path = os.path.abspath(os.path.expanduser(match["host_path"]))
+    host_path = host_path.replace(os.path.sep, "/")
+    container_path = match["container_path"]
+    for service in services:
+        if service:
+            mounts.append((service, host_path, container_path))
+    return mounts
+
+
+@lru_cache(maxsize=None)
+def parse_implicit_mount(value: str) -> list[tuple[str, str, str]]:
+    """
+    Argument is of the form "/host/path"
+    """
+    mounts: list[tuple[str, str, str]] = []
+    host_path = os.path.abspath(os.path.expanduser(value))
+    for service, container_path in hooks.Filters.COMPOSE_MOUNTS.iterate(
+        os.path.basename(host_path)
+    ):
+        mounts.append((service, host_path, container_path))
+    return mounts
diff --git a/tutor/bindmounts.py b/tutor/bindmounts.py
deleted file mode 100644
index d807358..0000000
--- a/tutor/bindmounts.py
+++ /dev/null
@@ -1,61 +0,0 @@
-import os
-
-from tutor.exceptions import TutorError
-from tutor.tasks import BaseComposeTaskRunner
-from tutor.utils import get_user_id
-
-
-def create(
-    runner: BaseComposeTaskRunner,
-    service: str,
-    path: str,
-) -> str:
-    volumes_root_path = get_root_path(runner.root)
-    volume_name = get_name(path)
-    container_volumes_root_path = "/tmp/volumes"
-    command = """rm -rf {volumes_path}/{volume_name}
-cp -r {src_path} {volumes_path}/{volume_name}
-chown -R {user_id} {volumes_path}/{volume_name}""".format(
-        volumes_path=container_volumes_root_path,
-        volume_name=volume_name,
-        src_path=path,
-        user_id=get_user_id(),
-    )
-
-    # Create volumes root dir if it does not exist. Otherwise it is created with root owner and might not be writable
-    # in the container, e.g: in the dev containers.
-    if not os.path.exists(volumes_root_path):
-        os.makedirs(volumes_root_path)
-
-    runner.docker_compose(
-        "run",
-        "--rm",
-        "--no-deps",
-        "--user=0",
-        "--volume",
-        f"{volumes_root_path}:{container_volumes_root_path}",
-        service,
-        "sh",
-        "-e",
-        "-c",
-        command,
-    )
-    return os.path.join(volumes_root_path, volume_name)
-
-
-def get_path(root: str, container_bind_path: str) -> str:
-    bind_basename = get_name(container_bind_path)
-    return os.path.join(get_root_path(root), bind_basename)
-
-
-def get_name(container_bind_path: str) -> str:
-    # We rstrip slashes, otherwise os.path.basename returns an empty string
-    # We don't use basename here as it will not work on Windows
-    name = container_bind_path.rstrip("/").split("/")[-1]
-    if not name:
-        raise TutorError("Mounting a container root folder is not supported")
-    return name
-
-
-def get_root_path(root: str) -> str:
-    return os.path.join(root, "volumes")
diff --git a/tutor/commands/compose.py b/tutor/commands/compose.py
index 44f5158..53112d0 100644
--- a/tutor/commands/compose.py
+++ b/tutor/commands/compose.py
@@ -1,17 +1,12 @@
 from __future__ import annotations
 
 import os
-import re
-import typing as t
-from copy import deepcopy
 
 import click
-from click.shell_completion import CompletionItem
-from typing_extensions import TypeAlias
 
 from tutor import config as tutor_config
 from tutor import env as tutor_env
-from tutor import fmt, hooks, serialize, utils
+from tutor import bindmount, hooks, utils
 from tutor.commands import jobs
 from tutor.commands.context import BaseTaskContext
 from tutor.core.hooks import Filter  # pylint: disable=unused-import
@@ -19,8 +14,6 @@ from tutor.exceptions import TutorError
 from tutor.tasks import BaseComposeTaskRunner
 from tutor.types import Config
 
-COMPOSE_FILTER_TYPE: TypeAlias = "Filter[dict[str, t.Any], []]"
-
 
 class ComposeTaskRunner(BaseComposeTaskRunner):
     def __init__(self, root: str, config: Config):
@@ -47,47 +40,6 @@ class ComposeTaskRunner(BaseComposeTaskRunner):
             *args, "--project-name", self.project_name, *command
         )
 
-    def update_docker_compose_tmp(
-        self,
-        compose_tmp_filter: COMPOSE_FILTER_TYPE,
-        compose_jobs_tmp_filter: COMPOSE_FILTER_TYPE,
-        docker_compose_tmp_path: str,
-        docker_compose_jobs_tmp_path: str,
-    ) -> None:
-        """
-        Update the contents of the docker-compose.tmp.yml and
-        docker-compose.jobs.tmp.yml files, which are generated at runtime.
-        """
-        compose_base: dict[str, t.Any] = {
-            "version": "{{ DOCKER_COMPOSE_VERSION }}",
-            "services": {},
-        }
-
-        # 1. Apply compose_tmp filter
-        # 2. Render the resulting dict
-        # 3. Serialize to yaml
-        # 4. Save to disk
-        docker_compose_tmp: str = serialize.dumps(
-            tutor_env.render_unknown(
-                self.config, compose_tmp_filter.apply(deepcopy(compose_base))
-            )
-        )
-        tutor_env.write_to(
-            docker_compose_tmp,
-            docker_compose_tmp_path,
-        )
-
-        # Same thing but with tmp jobs
-        docker_compose_jobs_tmp: str = serialize.dumps(
-            tutor_env.render_unknown(
-                self.config, compose_jobs_tmp_filter.apply(deepcopy(compose_base))
-            )
-        )
-        tutor_env.write_to(
-            docker_compose_jobs_tmp,
-            docker_compose_jobs_tmp_path,
-        )
-
     def run_task(self, service: str, command: str) -> int:
         """
         Run the "{{ service }}-job" service from local/docker-compose.jobs.yml with the
@@ -113,148 +65,22 @@ class ComposeTaskRunner(BaseComposeTaskRunner):
 
 
 class BaseComposeContext(BaseTaskContext):
-    COMPOSE_TMP_FILTER: COMPOSE_FILTER_TYPE = NotImplemented
-    COMPOSE_JOBS_TMP_FILTER: COMPOSE_FILTER_TYPE = NotImplemented
-
     def job_runner(self, config: Config) -> ComposeTaskRunner:
         raise NotImplementedError
 
 
-class MountParam(click.ParamType):
-    """
-    Parser for --mount arguments of the form "service1[,service2,...]:/host/path:/container/path".
-    """
-
-    name = "mount"
-    MountType = t.Tuple[str, str, str]
-    # Note that this syntax does not allow us to include colon ':' characters in paths
-    PARAM_REGEXP = (
-        r"(?P<services>[a-zA-Z0-9-_, ]+):(?P<host_path>[^:]+):(?P<container_path>[^:]+)"
-    )
-
-    def convert(
-        self,
-        value: str,
-        param: t.Optional["click.Parameter"],
-        ctx: t.Optional[click.Context],
-    ) -> list["MountType"]:
-        mounts = self.convert_explicit_form(value) or self.convert_implicit_form(value)
-        return mounts
-
-    def convert_explicit_form(self, value: str) -> list["MountParam.MountType"]:
-        """
-        Argument is of the form "containers:/host/path:/container/path".
-        """
-        match = re.match(self.PARAM_REGEXP, value)
-        if not match:
-            return []
-
-        mounts: list["MountParam.MountType"] = []
-        services: list[str] = [
-            service.strip() for service in match["services"].split(",")
-        ]
-        host_path = os.path.abspath(os.path.expanduser(match["host_path"]))
-        host_path = host_path.replace(os.path.sep, "/")
-        container_path = match["container_path"]
-        for service in services:
-            if not service:
-                self.fail(f"incorrect services syntax: '{match['services']}'")
-            mounts.append((service, host_path, container_path))
-        return mounts
-
-    def convert_implicit_form(self, value: str) -> list["MountParam.MountType"]:
-        """
-        Argument is of the form "/host/path"
-        """
-        mounts: list["MountParam.MountType"] = []
-        host_path = os.path.abspath(os.path.expanduser(value))
-        for service, container_path in hooks.Filters.COMPOSE_MOUNTS.iterate(
-            os.path.basename(host_path)
-        ):
-            mounts.append((service, host_path, container_path))
-        if not mounts:
-            raise self.fail(f"no mount found for {value}")
-        return mounts
-
-    def shell_complete(
-        self, ctx: click.Context, param: click.Parameter, incomplete: str
-    ) -> list[CompletionItem]:
-        """
-        Mount argument completion works only for the single path (implicit) form. The
-        reason is that colons break words in bash completion:
-        http://tiswww.case.edu/php/chet/bash/FAQ (E13)
-        Thus, we do not even attempt to auto-complete mount arguments that include
-        colons: such arguments will not even reach this method.
-        """
-        return [CompletionItem(incomplete, type="file")]
-
-
-mount_option = click.option(
-    "-m",
-    "--mount",
-    "mounts",
-    help="""Bind-mount a folder from the host in the right containers. This option can take two different forms. The first one is explicit: 'service1[,service2...]:/host/path:/container/path'. The other is implicit: '/host/path'. Arguments passed in the implicit form will be parsed by plugins to define the right folders to bind-mount from the host.""",
-    type=MountParam(),
-    multiple=True,
-)
-
-
-def mount_tmp_volumes(
-    all_mounts: tuple[list[MountParam.MountType], ...],
-    context: BaseComposeContext,
-) -> None:
-    for mounts in all_mounts:
-        for service, host_path, container_path in mounts:
-            mount_tmp_volume(service, host_path, container_path, context)
-
-
-def mount_tmp_volume(
-    service: str,
-    host_path: str,
-    container_path: str,
-    context: BaseComposeContext,
-) -> None:
-    """
-    Append user-defined bind-mounted volumes to the docker-compose.tmp file(s).
-
-    The service/host path/container path values are appended to the docker-compose
-    files by mean of two filters. Each dev/local environment is then responsible for
-    generating the files based on the output of these filters.
-
-    Bind-mounts that are associated to "*-job" services will be added to the
-    docker-compose jobs file.
-    """
-    fmt.echo_info(f"Bind-mount: {host_path} -> {container_path} in {service}")
-    compose_tmp_filter: COMPOSE_FILTER_TYPE = (
-        context.COMPOSE_JOBS_TMP_FILTER
-        if service.endswith("-job")
-        else context.COMPOSE_TMP_FILTER
-    )
-
-    @compose_tmp_filter.add()
-    def _add_mounts_to_docker_compose_tmp(
-        docker_compose: dict[str, t.Any],
-    ) -> dict[str, t.Any]:
-        services = docker_compose.setdefault("services", {})
-        services.setdefault(service, {"volumes": []})
-        services[service]["volumes"].append(f"{host_path}:{container_path}")
-        return docker_compose
-
-
 @click.command(
     short_help="Run all or a selection of services.",
     help="Run all or a selection of services. Docker images will be rebuilt where necessary.",
 )
 @click.option("--skip-build", is_flag=True, help="Skip image building")
 @click.option("-d", "--detach", is_flag=True, help="Start in daemon mode")
-@mount_option
 @click.argument("services", metavar="service", nargs=-1)
 @click.pass_obj
 def start(
     context: BaseComposeContext,
     skip_build: bool,
     detach: bool,
-    mounts: tuple[list[MountParam.MountType]],
     services: list[str],
 ) -> None:
     command = ["up", "--remove-orphans"]
@@ -264,7 +90,6 @@ def start(
         command.append("-d")
 
     # Start services
-    mount_tmp_volumes(mounts, context)
     config = tutor_config.load(context.root)
     context.job_runner(config).docker_compose(*command, *services)
 
@@ -313,21 +138,11 @@ def restart(context: BaseComposeContext, services: list[str]) -> None:
 
 
 @jobs.do_group
-@mount_option
-@click.pass_obj
-def do(context: BaseComposeContext, mounts: tuple[list[MountParam.MountType]]) -> None:
+def do() -> None:
     """
     Run a custom job in the right container(s).
     """
 
-    @hooks.Actions.DO_JOB.add()
-    def _mount_tmp_volumes(_job_name: str, *_args: t.Any, **_kwargs: t.Any) -> None:
-        """
-        We add this logic to an action callback because we do not want to trigger it
-        whenever we run `tutor local do <job> --help`.
-        """
-        mount_tmp_volumes(mounts, context)
-
 
 @click.command(
     short_help="Run a command in a new container",
@@ -338,18 +153,16 @@ def do(context: BaseComposeContext, mounts: tuple[list[MountParam.MountType]]) -
     ),
     context_settings={"ignore_unknown_options": True},
 )
-@mount_option
 @click.argument("args", nargs=-1, required=True)
 @click.pass_context
 def run(
     context: click.Context,
-    mounts: tuple[list[MountParam.MountType]],
     args: list[str],
 ) -> None:
     extra_args = ["--rm"]
     if not utils.is_a_tty():
         extra_args.append("-T")
-    context.invoke(dc_command, mounts=mounts, command="run", args=[*extra_args, *args])
+    context.invoke(dc_command, command="run", args=[*extra_args, *args])
 
 
 @click.command(
@@ -446,17 +259,14 @@ def status(context: click.Context) -> None:
     context_settings={"ignore_unknown_options": True},
     name="dc",
 )
-@mount_option
 @click.argument("command")
 @click.argument("args", nargs=-1)
 @click.pass_obj
 def dc_command(
     context: BaseComposeContext,
-    mounts: tuple[list[MountParam.MountType]],
     command: str,
     args: list[str],
 ) -> None:
-    mount_tmp_volumes(mounts, context)
     config = tutor_config.load(context.root)
     context.job_runner(config).docker_compose(command, *args)
 
@@ -466,8 +276,8 @@ def _mount_edx_platform(
     volumes: list[tuple[str, str]], name: str
 ) -> list[tuple[str, str]]:
     """
-    When mounting edx-platform with `--mount=/path/to/edx-platform`, bind-mount the host
-    repo in the lms/cms containers.
+    When mounting edx-platform with `tutor config save --append MOUNTS=/path/to/edx-platform`,
+    bind-mount the host repo in the lms/cms containers.
     """
     if name == "edx-platform":
         path = "/openedx/edx-platform"
@@ -482,6 +292,9 @@ def _mount_edx_platform(
     return volumes
 
 
+hooks.Filters.ENV_TEMPLATE_VARIABLES.add_item(("iter_mounts", bindmount.iter_mounts))
+
+
 def add_commands(command_group: click.Group) -> None:
     command_group.add_command(start)
     command_group.add_command(stop)
diff --git a/tutor/commands/dev.py b/tutor/commands/dev.py
index 124c6a9..f5f5df2 100644
--- a/tutor/commands/dev.py
+++ b/tutor/commands/dev.py
@@ -18,39 +18,21 @@ class DevTaskRunner(compose.ComposeTaskRunner):
         """
         super().__init__(root, config)
         self.project_name = get_typed(self.config, "DEV_PROJECT_NAME", str)
-        docker_compose_tmp_path = tutor_env.pathjoin(
-            self.root, "dev", "docker-compose.tmp.yml"
-        )
-        docker_compose_jobs_tmp_path = tutor_env.pathjoin(
-            self.root, "dev", "docker-compose.jobs.tmp.yml"
-        )
         self.docker_compose_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.yml"),
-            docker_compose_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.override.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.override.yml"),
         ]
         self.docker_compose_job_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.jobs.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.jobs.yml"),
-            docker_compose_jobs_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.jobs.override.yml"),
             tutor_env.pathjoin(self.root, "dev", "docker-compose.jobs.override.yml"),
         ]
-        # Update docker-compose.tmp files
-        self.update_docker_compose_tmp(
-            hooks.Filters.COMPOSE_DEV_TMP,
-            hooks.Filters.COMPOSE_DEV_JOBS_TMP,
-            docker_compose_tmp_path,
-            docker_compose_jobs_tmp_path,
-        )
 
 
 class DevContext(compose.BaseComposeContext):
-    COMPOSE_TMP_FILTER = hooks.Filters.COMPOSE_DEV_TMP
-    COMPOSE_JOBS_TMP_FILTER = hooks.Filters.COMPOSE_DEV_JOBS_TMP
-
     def job_runner(self, config: Config) -> DevTaskRunner:
         return DevTaskRunner(self.root, config)
 
@@ -64,15 +46,12 @@ def dev(context: click.Context) -> None:
 @click.command(help="Configure and run Open edX from scratch, for development")
 @click.option("-I", "--non-interactive", is_flag=True, help="Run non-interactively")
 @click.option("-p", "--pullimages", is_flag=True, help="Update docker images")
-@compose.mount_option
 @click.pass_context
 def launch(
     context: click.Context,
     non_interactive: bool,
     pullimages: bool,
-    mounts: tuple[list[compose.MountParam.MountType]],
 ) -> None:
-    compose.mount_tmp_volumes(mounts, context.obj)
     utils.warn_macos_docker_memory()
 
     click.echo(fmt.title("Interactive platform configuration"))
diff --git a/tutor/commands/images.py b/tutor/commands/images.py
index 1dfce27..ca5e719 100644
--- a/tutor/commands/images.py
+++ b/tutor/commands/images.py
@@ -1,12 +1,13 @@
 from __future__ import annotations
 
+import os
 import typing as t
 
 import click
 
 from tutor import config as tutor_config
 from tutor import env as tutor_env
-from tutor import exceptions, hooks, images, utils
+from tutor import exceptions, hooks, images, types, utils
 from tutor.commands.context import Context
 from tutor.core.hooks import Filter
 from tutor.types import Config
@@ -148,16 +149,26 @@ def build(
         command_args.append(f"--output={docker_output}")
     if docker_args:
         command_args += docker_args
+    # Build context mounts
+    build_contexts = get_image_build_contexts(config)
+
     for image in image_names:
-        for _name, path, tag, custom_args in find_images_to_build(config, image):
+        for name, path, tag, custom_args in find_images_to_build(config, image):
             image_build_args = [*command_args, *custom_args]
+
+            # Registry cache
             if not no_registry_cache:
-                # Use registry cache
                 image_build_args.append(f"--cache-from=type=registry,ref={tag}-cache")
             if cache_to_registry:
                 image_build_args.append(
                     f"--cache-to=type=registry,mode=max,ref={tag}-cache"
                 )
+
+            # Build contexts
+            for host_path, stage_name in build_contexts.get(name, []):
+                image_build_args.append(f"--build-context={stage_name}={host_path}")
+
+            # Build
             images.build(
                 tutor_env.pathjoin(context.root, *path),
                 tag,
@@ -165,6 +176,41 @@ def build(
             )
 
 
+def get_image_build_contexts(config: Config) -> dict[str, list[tuple[str, str]]]:
+    """
+    Return all build contexts for all images.
+
+    A build context is to bind-mount a host directory at build-time. This is useful, for
+    instance to build a Docker image with a local git checkout of a remote repo.
+
+    Users configure bind-mounts with the `MOUNTS` config setting. Plugins can then
+    automaticall add build contexts based on these values.
+    """
+    user_mounts = types.get_typed(config, "MOUNTS", list)
+    build_contexts: dict[str, list[tuple[str, str]]] = {}
+    for user_mount in user_mounts:
+        for image_name, stage_name in hooks.Filters.IMAGES_BUILD_MOUNTS.iterate(
+            user_mount
+        ):
+            if image_name not in build_contexts:
+                build_contexts[image_name] = []
+            build_contexts[image_name].append((user_mount, stage_name))
+    return build_contexts
+
+
+@hooks.Filters.IMAGES_BUILD_MOUNTS.add()
+def _mount_edx_platform(
+    volumes: list[tuple[str, str]], path: str
+) -> list[tuple[str, str]]:
+    """
+    Automatically add an edx-platform repo from the host to the build context whenever
+    it is added to the `MOUNTS` setting.
+    """
+    if os.path.basename(path) == "edx-platform":
+        volumes.append(("openedx", "edx-platform"))
+    return volumes
+
+
 @click.command(short_help="Pull images from the Docker registry")
 @click.argument("image_names", metavar="image", nargs=-1)
 @click.pass_obj
diff --git a/tutor/commands/local.py b/tutor/commands/local.py
index 9a91392..9ead815 100644
--- a/tutor/commands/local.py
+++ b/tutor/commands/local.py
@@ -23,38 +23,19 @@ class LocalTaskRunner(compose.ComposeTaskRunner):
         """
         super().__init__(root, config)
         self.project_name = get_typed(self.config, "LOCAL_PROJECT_NAME", str)
-        docker_compose_tmp_path = tutor_env.pathjoin(
-            self.root, "local", "docker-compose.tmp.yml"
-        )
-        docker_compose_jobs_tmp_path = tutor_env.pathjoin(
-            self.root, "local", "docker-compose.jobs.tmp.yml"
-        )
         self.docker_compose_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.yml"),
             tutor_env.pathjoin(self.root, "local", "docker-compose.prod.yml"),
-            docker_compose_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.override.yml"),
         ]
         self.docker_compose_job_files += [
             tutor_env.pathjoin(self.root, "local", "docker-compose.jobs.yml"),
-            docker_compose_jobs_tmp_path,
             tutor_env.pathjoin(self.root, "local", "docker-compose.jobs.override.yml"),
         ]
 
-        # Update docker-compose.tmp files
-        self.update_docker_compose_tmp(
-            hooks.Filters.COMPOSE_LOCAL_TMP,
-            hooks.Filters.COMPOSE_LOCAL_JOBS_TMP,
-            docker_compose_tmp_path,
-            docker_compose_jobs_tmp_path,
-        )
-
 
 # pylint: disable=too-few-public-methods
 class LocalContext(compose.BaseComposeContext):
-    COMPOSE_TMP_FILTER = hooks.Filters.COMPOSE_LOCAL_TMP
-    COMPOSE_JOBS_TMP_FILTER = hooks.Filters.COMPOSE_LOCAL_JOBS_TMP
-
     def job_runner(self, config: Config) -> LocalTaskRunner:
         return LocalTaskRunner(self.root, config)
 
@@ -66,17 +47,14 @@ def local(context: click.Context) -> None:
 
 
 @click.command(help="Configure and run Open edX from scratch")
-@compose.mount_option
 @click.option("-I", "--non-interactive", is_flag=True, help="Run non-interactively")
 @click.option("-p", "--pullimages", is_flag=True, help="Update docker images")
 @click.pass_context
 def launch(
     context: click.Context,
-    mounts: tuple[list[compose.MountParam.MountType]],
     non_interactive: bool,
     pullimages: bool,
 ) -> None:
-    compose.mount_tmp_volumes(mounts, context.obj)
     utils.warn_macos_docker_memory()
 
     run_upgrade_from_release = tutor_env.should_upgrade_from_release(context.obj.root)
diff --git a/tutor/hooks/catalog.py b/tutor/hooks/catalog.py
index 9db9d70..a21fd51 100644
--- a/tutor/hooks/catalog.py
+++ b/tutor/hooks/catalog.py
@@ -227,33 +227,20 @@ class Filters:
         "commands:pre-init"
     )
 
-    #: Same as :py:data:`COMPOSE_LOCAL_JOBS_TMP` but for the development environment.
-    COMPOSE_DEV_JOBS_TMP: Filter[Config, []] = filters.get("compose:dev-jobs:tmp")
-
-    #: Same as :py:data:`COMPOSE_LOCAL_TMP` but for the development environment.
-    COMPOSE_DEV_TMP: Filter[Config, []] = filters.get("compose:dev:tmp")
-
-    #: Same as :py:data:`COMPOSE_LOCAL_TMP` but for jobs
-    COMPOSE_LOCAL_JOBS_TMP: Filter[Config, []] = filters.get("compose:local-jobs:tmp")
-
-    #: Contents of the (local|dev)/docker-compose.tmp.yml files that will be generated at
-    #: runtime. This is used for instance to bind-mount folders from the host (see
-    #: :py:data:`COMPOSE_MOUNTS`)
-    #:
-    #: :parameter dict[str, ...] docker_compose_tmp: values which will be serialized to local/docker-compose.tmp.yml.
-    #:   Keys and values will be rendered before saving, such that you may include ``{{ ... }}`` statements.
-    COMPOSE_LOCAL_TMP: Filter[Config, []] = filters.get("compose:local:tmp")
-
     #: List of folders to bind-mount in docker-compose containers, either in ``tutor local`` or ``tutor dev``.
     #:
-    #: Many ``tutor local`` and ``tutor dev`` commands support ``--mounts`` options
-    #: that allow plugins to define custom behaviour at runtime. For instance
-    #: ``--mount=/path/to/edx-platform`` would cause this host folder to be
-    #: bind-mounted in different containers (lms, lms-worker, cms, cms-worker) at the
+    #: This filter is for processing values of the ``MOUNTS`` setting such as::
+    #:
+    #:     tutor config save --append MOUNTS=/path/to/edx-platform
+    #:
+    #: In this example, this host folder would be bind-mounted in different containers
+    #: (lms, lms-worker, cms, cms-worker, lms-job, cms-job) at the
     #: /openedx/edx-platform location. Plugin developers may implement this filter to
     #: define custom behaviour when mounting folders that relate to their plugins. For
-    #: instance, the ecommerce plugin may process the ``--mount=/path/to/ecommerce``
-    #: option.
+    #: instance, the ecommerce plugin may process the ``/path/to/ecommerce`` value.
+    #:
+    #: To also bind-mount these folder at build time, implement also the
+    #: :py:data:`IMAGES_BUILD_MOUNTS` filter.
     #:
     #: :parameter list[tuple[str, str]] mounts: each item is a ``(service, path)``
     #:   tuple, where ``service`` is the name of the docker-compose service and ``path`` is
@@ -262,7 +249,7 @@ class Filters:
     #:   the ``path`` because it will fail on Windows.
     #: :parameter str name: basename of the host-mounted folder. In the example above,
     #:   this is "edx-platform". When implementing this filter you should check this name to
-    #:   conditionnally add mounts.
+    #:   conditionally add mounts.
     COMPOSE_MOUNTS: Filter[list[tuple[str, str]], [str]] = filters.get("compose:mounts")
 
     #: Declare new default configuration settings that don't necessarily have to be saved in the user
@@ -402,6 +389,26 @@ class Filters:
         list[tuple[str, tuple[str, ...], str, tuple[str, ...]]], [Config]
     ] = filters.get("images:build")
 
+    #: List of host directories to be automatically bind-mounted in Docker images at
+    #: build time. For instance, this is useful to build Docker images using a custom
+    #: repository on the host.
+    #:
+    #: This filter works similarly to the :py:data:`COMPOSE_MOUNTS` filter, with a few differences.
+    #:
+    #: :parameter list[tuple[str, str]] mounts: each item is a pair of ``(name, value)``
+    #:   used to generate a build context at build time. See the corresponding `Docker
+    #:   documentation <https://docs.docker.com/engine/reference/commandline/buildx_build/#build-context>`__.
+    #:   The following option will be added to the ``docker buildx build`` command:
+    #:   ``--build-context={name}={value}``. If the Dockerfile contains a "name" stage, then
+    #:   that stage will be replaced by the corresponding directory on the host.
+    #: :parameter str name: full path to the host-mounted folder. As opposed to
+    #:   :py:data:`COMPOSE_MOUNTS`, this is not just the basename, but the full path. When
+    #:   implementing this filter you should check this path (for instance: with
+    #:   ``os.path.basename(path)``) to conditionally add mounts.
+    IMAGES_BUILD_MOUNTS: Filter[list[tuple[str, str]], [str]] = filters.get(
+        "images:build:mounts"
+    )
+
     #: List of images to be pulled when we run ``tutor images pull ...``.
     #:
     #: :parameter list[tuple[str, str]] tasks: list of ``(name, tag)`` tuples.
diff --git a/tutor/images.py b/tutor/images.py
index 0d1e80b..dc640d0 100644
--- a/tutor/images.py
+++ b/tutor/images.py
@@ -9,7 +9,7 @@ def get_tag(config: Config, name: str) -> str:
 
 def build(path: str, tag: str, *args: str) -> None:
     fmt.echo_info(f"Building image {tag}")
-    build_command = ["build", "-t", tag, *args, path]
+    build_command = ["build", f"--tag={tag}", *args, path]
     if utils.is_buildkit_enabled():
         build_command.insert(0, "buildx")
     command = hooks.Filters.DOCKER_BUILD_COMMAND.apply(build_command)
diff --git a/tutor/templates/config/defaults.yml b/tutor/templates/config/defaults.yml
index da341ed..642d38a 100644
--- a/tutor/templates/config/defaults.yml
+++ b/tutor/templates/config/defaults.yml
@@ -43,6 +43,7 @@ MONGODB_USERNAME: ""
 MONGODB_PASSWORD: ""
 MONGODB_REPLICA_SET: ""
 MONGODB_USE_SSL: false
+MOUNTS: []
 OPENEDX_AWS_ACCESS_KEY: ""
 OPENEDX_AWS_SECRET_ACCESS_KEY: ""
 OPENEDX_CACHE_REDIS_DB: 1
diff --git a/tutor/templates/local/docker-compose.jobs.yml b/tutor/templates/local/docker-compose.jobs.yml
index 37e116c..c70fa23 100644
--- a/tutor/templates/local/docker-compose.jobs.yml
+++ b/tutor/templates/local/docker-compose.jobs.yml
@@ -27,6 +27,9 @@ services:
         - ../apps/openedx/settings/lms:/openedx/edx-platform/lms/envs/tutor:ro
         - ../apps/openedx/settings/cms:/openedx/edx-platform/cms/envs/tutor:ro
         - ../apps/openedx/config:/openedx/config:ro
+        {%- for mount in iter_mounts(MOUNTS, "lms-job") %}
+        - {{ mount }}
+        {%- endfor %}
       depends_on: {{ [("mysql", RUN_MYSQL), ("mongodb", RUN_MONGODB)]|list_if }}
 
     cms-job:
@@ -38,6 +41,9 @@ services:
         - ../apps/openedx/settings/lms:/openedx/edx-platform/lms/envs/tutor:ro
         - ../apps/openedx/settings/cms:/openedx/edx-platform/cms/envs/tutor:ro
         - ../apps/openedx/config:/openedx/config:ro
+        {%- for mount in iter_mounts(MOUNTS, "cms-job") %}
+        - {{ mount }}
+        {%- endfor %}
       depends_on: {{ [("mysql", RUN_MYSQL), ("mongodb", RUN_MONGODB), ("elasticsearch", RUN_ELASTICSEARCH), ("redis", RUN_REDIS)]|list_if }}
 
     {{ patch("local-docker-compose-jobs-services")|indent(4) }}
diff --git a/tutor/templates/local/docker-compose.yml b/tutor/templates/local/docker-compose.yml
index b30afb1..2dc6b72 100644
--- a/tutor/templates/local/docker-compose.yml
+++ b/tutor/templates/local/docker-compose.yml
@@ -24,7 +24,7 @@ services:
 
   ############# External services
 
-  {% if RUN_MONGODB %}
+  {% if RUN_MONGODB -%}
   mongodb:
     image: {{ DOCKER_IMAGE_MONGODB }}
     # Use WiredTiger in all environments, just like at edx.org
@@ -35,9 +35,9 @@ services:
       - ../../data/mongodb:/data/db
     depends_on:
       - permissions
-  {% endif %}
+  {%- endif %}
 
-  {% if RUN_MYSQL %}
+  {% if RUN_MYSQL -%}
   mysql:
     image: {{ DOCKER_IMAGE_MYSQL }}
     command: mysqld --character-set-server=utf8 --collation-server=utf8_general_ci
@@ -47,9 +47,9 @@ services:
       - ../../data/mysql:/var/lib/mysql
     environment:
       MYSQL_ROOT_PASSWORD: "{{ MYSQL_ROOT_PASSWORD }}"
-  {% endif %}
+  {%- endif %}
 
-  {% if RUN_ELASTICSEARCH %}
+  {% if RUN_ELASTICSEARCH -%}
   elasticsearch:
     image: {{ DOCKER_IMAGE_ELASTICSEARCH }}
     environment:
@@ -67,9 +67,9 @@ services:
       - ../../data/elasticsearch:/usr/share/elasticsearch/data
     depends_on:
       - permissions
-  {% endif %}
+  {%- endif %}
 
-  {% if RUN_REDIS %}
+  {% if RUN_REDIS -%}
   redis:
     image: {{ DOCKER_IMAGE_REDIS }}
     working_dir: /openedx/redis/data
@@ -81,16 +81,16 @@ services:
     restart: unless-stopped
     depends_on:
       - permissions
-  {% endif %}
+  {%- endif %}
 
-  {% if RUN_SMTP %}
+  {% if RUN_SMTP -%}
   smtp:
     image: {{ DOCKER_IMAGE_SMTP }}
     restart: unless-stopped
     user: "100:101"
     environment:
       HOSTNAME: "{{ LMS_HOST }}"
-  {% endif %}
+  {%- endif %}
 
   ############# LMS and CMS
 
@@ -108,6 +108,9 @@ services:
       - ../apps/openedx/uwsgi.ini:/openedx/edx-platform/uwsgi.ini:ro
       - ../../data/lms:/openedx/data
       - ../../data/openedx-media:/openedx/media
+      {%- for mount in iter_mounts(MOUNTS, "lms") %}
+      - {{ mount }}
+      {%- endfor %}
     depends_on:
       - permissions
       {% if RUN_MYSQL %}- mysql{% endif %}
@@ -131,6 +134,9 @@ services:
       - ../apps/openedx/uwsgi.ini:/openedx/edx-platform/uwsgi.ini:ro
       - ../../data/cms:/openedx/data
       - ../../data/openedx-media:/openedx/media
+      {%- for mount in iter_mounts(MOUNTS, "cms") %}
+      - {{ mount }}
+      {%- endfor %}
     depends_on:
       - permissions
       - lms
@@ -156,6 +162,9 @@ services:
       - ../apps/openedx/config:/openedx/config:ro
       - ../../data/lms:/openedx/data
       - ../../data/openedx-media:/openedx/media
+      {%- for mount in iter_mounts(MOUNTS, "lms-worker") %}
+      - {{ mount }}
+      {%- endfor %}
     depends_on:
       - lms
 
@@ -172,6 +181,9 @@ services:
       - ../apps/openedx/config:/openedx/config:ro
       - ../../data/cms:/openedx/data
       - ../../data/openedx-media:/openedx/media
+      {%- for mount in iter_mounts(MOUNTS, "cms-worker") %}
+      - {{ mount }}
+      {%- endfor %}
     depends_on:
       - cms