diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 5fb909f8..aae9ffef 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -16,7 +16,7 @@ build:
 
 # Build documentation in the "docs/" directory with Sphinx
 sphinx:
-  configuration: docs/sourcse/conf.py
+  configuration: doc/source/conf.py
   # You can configure Sphinx to use a different builder, for instance use the dirhtml builder for simpler URLs
   # builder: "dirhtml"
   # Fail on all warnings to avoid broken references
diff --git a/src/batou/main.py b/src/batou/main.py
index 2b8c7449..f1066e98 100644
--- a/src/batou/main.py
+++ b/src/batou/main.py
@@ -166,6 +166,18 @@ def main(args: Optional[list] = None) -> None:
     )
     p.set_defaults(func=batou.secrets.manage.remove_user)
 
+    p = sp.add_parser(
+        "reencrypt",
+        help="Re-encrypt all secret files with the current members.",
+    )
+    p.set_defaults(func=p.print_usage)
+    p.add_argument(
+        "--environments",
+        default="",
+        help="The environments to update. Update all if not specified.",
+    )
+    p.set_defaults(func=batou.secrets.manage.reencrypt)
+
     # migrate
     migrate = subparsers.add_parser(
         "migrate",
diff --git a/src/batou/secrets/__init__.py b/src/batou/secrets/__init__.py
index 1f745832..bc5ffae5 100644
--- a/src/batou/secrets/__init__.py
+++ b/src/batou/secrets/__init__.py
@@ -372,7 +372,7 @@ class ConfigFileSecretProvider(SecretProvider):
         raise NotImplementedError("_get_file() not implemented.")
 
     def write_file(self, file: EncryptedFile, content: bytes):
-        recipients = self._get_recipients()
+        recipients = self._get_recipients_for_encryption()
         if not recipients:
             raise ValueError(
                 "No recipients found for environment. "
@@ -385,6 +385,14 @@ class ConfigFileSecretProvider(SecretProvider):
         with self.config_file:
             self.write_config(content)
 
+    def _get_recipients(self) -> List[str]:
+        recipients = self.config.get("batou", "members")
+        if recipients.value is None:
+            return []
+        recipients = re.split(r"(\n|,)+", recipients.value)
+        recipients = [r.strip() for r in recipients if r.strip()]
+        return recipients
+
 
 class GPGSecretProvider(ConfigFileSecretProvider):
     def __init__(self, environment: "Environment"):
@@ -421,13 +429,8 @@ class GPGSecretProvider(ConfigFileSecretProvider):
             writeable,
         )
 
-    def _get_recipients(self) -> List[str]:
-        recipients = self.config.get("batou", "members")
-        if recipients.value is None:
-            return []
-        recipients = re.split(r"(\n|,)+", recipients.value)
-        recipients = [r.strip() for r in recipients if r.strip()]
-        return recipients
+    def _get_recipients_for_encryption(self) -> List[str]:
+        return self._get_recipients()
 
     def write_config(self, content: bytes):
         config = ConfigUpdater().read_string(content.decode("utf-8"))
@@ -562,12 +565,8 @@ class AGESecretProvider(ConfigFileSecretProvider):
             writeable,
         )
 
-    def _get_recipients(self) -> List[str]:
-        recipients = self.config.get("batou", "members")
-        if recipients.value is None:
-            return []
-        recipients = re.split(r"(\n|,)+", recipients.value)
-        recipients = [r.strip() for r in recipients if r.strip()]
+    def _get_recipients_for_encryption(self) -> List[str]:
+        recipients = self._get_recipients()
         return process_age_recipients(
             recipients,
             pathlib.Path(self.environment.base_dir)
diff --git a/src/batou/secrets/manage.py b/src/batou/secrets/manage.py
index e5300f91..f518126b 100644
--- a/src/batou/secrets/manage.py
+++ b/src/batou/secrets/manage.py
@@ -3,7 +3,7 @@ import sys
 from configupdater import ConfigUpdater
 
 from batou import AgeCallError, GPGCallError
-from batou.environment import Environment
+from batou.environment import Environment, UnknownEnvironmentError
 
 
 def summary():
@@ -44,10 +44,6 @@ def add_user(keyid, environments, **kw):
             environment.secret_provider.write_config(
                 str(config).encode("utf-8")
             )
-    if not environments_:
-        raise UnknownEnvironmentError(
-            [e.strip() for e in environments.split(",")]
-        )
 
 
 def remove_user(keyid, environments, **kw):
@@ -69,7 +65,19 @@ def remove_user(keyid, environments, **kw):
             environment.secret_provider.write_config(
                 str(config).encode("utf-8")
             )
-    if not environments:
-        raise UnknownEnvironmentError(
-            [e.strip() for e in environments.split(",")]
-        )
+
+
+def reencrypt(environments, **kw):
+    """Re-encrypt all secrets in given environments.
+
+    If environments is not given, all secrets are re-encrypted.
+
+    """
+    environments_ = Environment.filter(environments)
+    for environment in environments_:
+        environment.load_secrets()
+        with environment.secret_provider.edit():
+            config = environment.secret_provider.config
+            environment.secret_provider.write_config(
+                str(config).encode("utf-8")
+            )

diff --git a/src/batou/secrets/tests/test_manage.py b/src/batou/secrets/tests/test_manage.py
index ca9f3c73..5257b645 100644
--- a/src/batou/secrets/tests/test_manage.py
+++ b/src/batou/secrets/tests/test_manage.py
@@ -1,12 +1,14 @@
+import glob
 import os
 import shutil
+import sys
 import textwrap
 
 import pytest
 
 from batou.environment import UnknownEnvironmentError
 
-from ..manage import add_user, remove_user, summary
+from ..manage import add_user, reencrypt, remove_user, summary
 
 
 @pytest.mark.parametrize("func", (add_user, remove_user))
@@ -38,6 +40,32 @@ def test_manage__2(tmp_path, monkeypatch, capsys):
     assert "306151601E813A47" in out
 
 
+@pytest.mark.skipif(
+    sys.version_info < (3, 7),
+    reason="age is available in tests with python 3.7 only",
+)
+def test_manage__2_age(tmp_path, monkeypatch, capsys):
+    """It allows to add/remove_users in an age encrypted environment."""
+    shutil.copytree("examples/tutorial-secrets", tmp_path / "tutorial-secrets")
+    monkeypatch.chdir(tmp_path / "tutorial-secrets")
+
+    key_name = "https://github.com/ctheune.keys"
+
+    summary()
+    out, err = capsys.readouterr()
+    assert key_name in out
+
+    remove_user(key_name, "age")
+    summary()
+    out, err = capsys.readouterr()
+    assert key_name not in out
+
+    add_user(key_name, "age")
+    summary()
+    out, err = capsys.readouterr()
+    assert key_name in out
+
+
 def test_manage__summary__1(capsys, monkeypatch):
     """It prints a summary of the environments, members and secret files."""
     monkeypatch.chdir("examples/errors")
@@ -77,3 +105,34 @@ def test_manage__summary__3(capsys, monkeypatch):
     expected = "secretserror\n\t members"
     assert expected in out
     assert err == ""
+
+
+@pytest.mark.skipif(
+    sys.version_info < (3, 7),
+    reason="age is available in tests with python 3.7 only",
+)
+def test_manage__reencrypt__1(tmp_path, monkeypatch, capsys):
+    """It re-encrypts all files with the current members."""
+    shutil.copytree("examples/tutorial-secrets", tmp_path / "tutorial-secrets")
+
+    monkeypatch.chdir(tmp_path / "tutorial-secrets")
+
+    # read files environments/*/secret*
+    # and make sure all of them change
+    # when we re-encrypt
+
+    old = {}
+    for path in glob.glob("environments/*/secret*"):
+        with open(path, "rb") as f:
+            old[path] = f.read()
+
+    reencrypt("")  # empty string means all environments
+    new = {}
+    for path in glob.glob("environments/*/secret*"):
+        with open(path, "rb") as f:
+            new[path] = f.read()
+
+    for path in old:
+        assert old[path] != new[path]
+
+    assert set(old) == set(new)

age-based encryption - need general command to update/reencrypt all secrets in all environments
Adding a new person requires to re-encrypt the files. AFAIK currently one has to edit (and change!) all environments to fetch updates for the keys end reencrypt and do that manually for all environments.

I think we need something like a `secrets update` command.

Also, there seems to be a bug with the existing add/remove commands (which are gpg-specific) and the "environments" parameter seems broken.
src/batou/secrets/tests/test_manage.py::test_manage__1[add_user] src/batou/secrets/tests/test_manage.py::test_manage__1[remove_user] src/batou/secrets/tests/test_manage.py::test_manage__summary__2