Bump version to 4.6.0

Write the completion time and backup directory to
$XDG_STATE_HOME/simple_backup/last_backup after each successful backup
(as the target user when run as root), for status bar reminders.
--last-backup prints it.

.gitignore

@@ -1,3 +1,4 @@
+CLAUDE.md
 .idea/
 __pycache__/
 test/

PKGBUILD

@@ -4,8 +4,8 @@
 
 pkgname=simple_backup
 pkgdesc='Simple backup script that uses rsync to copy files'
-pkgver=4.4.0
-pkgrel=2
+pkgver=4.5.0
+pkgrel=1
 url="https://git.shouldnt.work/fuxino/$pkgname"
 arch=('any')
 license=('GPL-3.0-or-later')
@@ -24,7 +24,7 @@ checkdepends=('python-pytest'
 conflicts=('simple_backup-git')
 source=("git+$url?signed#tag=$pkgver")
 validpgpkeys=('7E12BC1FF3B6EDB2CD8053EB981A2B2A3BBF5514')
-sha256sums=('cc5944558ed4bc30a0d1a00b49dfced371909dd6c4f39b0c1ccf8f39b445e907')
+sha256sums=('c0f7c38d99208e1327c0a6af1d58d5d13797d1cef54f99e1b2fcb4f4a9480609')
 
 build()
 {

README.md

@@ -22,12 +22,15 @@ sudo pacman -Syu rsync
 
 Optional dependencies are systemd-python to enable using systemd journal for logging, dbus-python for desktop notifications, and paramiko (version 3.2 or later) for remote backup.
 
-## Install
+## Installation
 For Arch Linux and Arch-based distros, two packages are available in the AUR (aur.archlinux.org):
 - **simple_backup** for the release version
 - **simple_backup-git** for the git version
 
-To install it from source, first clone the repository:
+Install one with your AUR helper, e.g. `aur sync simple_backup` with aurutils.
+
+### Other distributions
+First clone the repository:
 
 ```bash
 git clone https://git.shouldnt.work/fuxino/simple_backup.git
@@ -59,6 +62,17 @@ The number of old backups to keep can be set with the --keep (or -k) argument (o
 Old backups are only removed if rsync completes successfully, so that they are not deleted when the new backup may be incomplete.
 The only rsync error that is ignored is return code 24 (source files vanished during the transfer), which is common when backing up a live system.
 
+## Last backup
+After each successful backup, simple_backup saves its time and directory to `~/.local/state/simple_backup/last_backup` (or `$XDG_STATE_HOME/simple_backup/last_backup`).
+When run with sudo or doas, the file goes to the home directory of the user who ran the command.
+Print it with:
+
+```bash
+simple_backup --last-backup
+```
+
+The file has two lines: the completion time in ISO 8601 format (e.g. `2026-10-25T14:03:12+02:00`) and the backup directory, so scripts (e.g. a status bar indicator) can easily read it to remind you when a backup is overdue.
+
 ## Remote backup
 > **Warning**
 > This feature is experimental
@@ -66,6 +80,7 @@ The only rsync error that is ignored is return code 24 (source files vanished du
 It's possible to use a remote server as destination for the backup. Just use the --ssh-user and --ssh-host arguments (or set them in the configuration file).
 Both are required: if only one of them is set, simple_backup exits with an error.
 For this to work, rsync must be installed on the server too.
+The host can be an alias from `~/.ssh/config`: its HostName, Port and IdentityFile are used (ProxyJump and ProxyCommand are not supported).
 
 The output directory is a path on the server. A leading '~' and relative paths refer to the user's home directory on the server.
 On the command line, quote '~' so that your local shell doesn't expand it:

man/simple_backup.1

@@ -1,4 +1,4 @@
-.TH SIMPLE_BACKUP 1 2026-10-15 SIMPLE_BACKUP 4.4.1
+.TH SIMPLE_BACKUP 1 2026-10-25 SIMPLE_BACKUP 4.6.0
 .SH NAME
 simple_backup \- Backup files and folders using rsync
 .SH SYNOPSIS
@@ -145,6 +145,11 @@ needs to be allowed to run without password in the same way.
 .TP
 .B \-\-numeric\-ids
 Use rsync \-\-numeric\-ids option. This causes rsync to use numeric uid/gid instead of trying to map uid/gid names from the local machine to the server.
+.TP
+.B \-\-last\-backup
+Print the date and directory of the last successful backup, then exit. The exit status is 0, or 1
+if no backup has been recorded yet or the state file can\(aqt be read (see
+.BR FILES ).
 .SH CONFIGURATION
 An example configuration file is provided at \(aq/usr/share/doc/simple_backup/simple_backup.conf\(aq.
 Copy it to the default location ($HOME/.config/simple_backup) and edit it as needed.
@@ -152,6 +157,8 @@ Copy it to the default location ($HOME/.config/simple_backup) and edit it as nee
 It is possible to choose a directory on a remote server as destination for the backup. The files
 are copied by rsync through SSH. Server hostname and username must be specified, either in the
 configuration file, or on the command line (\(aq\-\-ssh\-host\(aq and \(aq\-\-ssh\-user\(aq options).
+The host can be an alias from \fI~/.ssh/config\fR: its HostName, Port and IdentityFile are used
+(ProxyJump and ProxyCommand are not supported).
 .P
 The output directory is a path on the server. A leading \(aq~\(aq and relative paths refer to the
 home directory of the user on the server. On the command line, quote \(aq~\(aq so that the local
@@ -207,13 +214,23 @@ Backup failed because output directory for storing the backup does not exist.
 Permission denied to access the output directory.
 .TP
 .B 4
-rsync error (rsync returned a value other than 0 or 24).
+rsync error (rsync returned a value other than 0 or 24, or rsync is not installed).
 .TP
 .B 5
 SSH connection failed.
 .TP
 .B 6
 Bad configuration file or options (for example, only one of SSH host and SSH user specified).
+.SH FILES
+.TP
+.I $XDG_STATE_HOME/simple_backup/last_backup
+Written after each successful backup (local or remote), replacing the previous one. The first line
+is the completion time in ISO 8601 format with the UTC offset (for example
+\(aq2026\-10\-25T14:03:12+02:00\(aq), the second line the backup directory (prefixed with
+\(aquser@host:\(aq for remote backups). The default location is
+\fI~/.local/state/simple_backup/last_backup\fR. When running as root with sudo, doas or \-\-user,
+the file is written to that user\(aqs \fI~/.local/state\fR and owned by them. Useful for scripts
+that remind you when a backup is overdue.
 .SH SEE ALSO
 .BR rsync (1)
 .SH AUTHORS

pyproject.toml

@@ -57,6 +57,12 @@ warn_unused_ignores = true
 module = ["paramiko", "systemd", "dbus"]
 ignore_missing_imports = true
 
+[tool.ruff]
+line-length = 120
+
+[tool.ruff.lint]
+select = ["E", "F", "W", "I", "B", "UP"]
+
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 # Import the repo copy, not an installed one

simple_backup/__init__.py

@@ -1,3 +1,3 @@
 """Init."""
 
-__version__ = '4.4.1'
+__version__ = '4.6.0'

simple_backup/simple_backup.py

@@ -14,27 +14,28 @@ Classes:
 # Avoid evaluating annotations at definition time, as they reference optional modules (paramiko)
 from __future__ import annotations
 
-# Import libraries
-import sys
-import os
-import pwd
-import io
-import re
-from typing import Callable, Iterator, List, Optional, ParamSpec, TypedDict, TypeVar
-import warnings
-from functools import wraps
-from shutil import get_terminal_size, rmtree, which
-import shlex
 import argparse
 import configparser
+import io
 import logging
-from logging import StreamHandler
-from timeit import default_timer
-from subprocess import Popen, PIPE, STDOUT
+import os
+import pwd
+import re
+import shlex
+import sys
+import warnings
+from collections import deque
+from collections.abc import Callable, Iterator
 from datetime import datetime
-from tempfile import mkstemp
+from functools import wraps
 from getpass import GetPassWarning, getpass
 from glob import glob
+from logging import StreamHandler
+from shutil import get_terminal_size, rmtree, which
+from subprocess import PIPE, STDOUT, Popen
+from tempfile import mkstemp
+from timeit import default_timer
+from typing import Any, ParamSpec, TypedDict, TypeVar
 
 try:
     import paramiko
@@ -204,9 +205,9 @@ class Backup:
             Perform the backup
     """
 
-    def __init__(self, inputs: Optional[List[str]], output: Optional[str], exclude: Optional[List[str]],
-                 keep: Optional[int], options: str,
-                 ssh_host: Optional[str] = None, ssh_user: Optional[str] = None, ssh_keyfile: Optional[str] = None,
+    def __init__(self, inputs: list[str] | None, output: str | None, exclude: list[str] | None,
+                 keep: int | None, options: str,
+                 ssh_host: str | None = None, ssh_user: str | None = None, ssh_keyfile: str | None = None,
                  remote_sudo: bool = False, remove_before: bool = False, verbose: bool = False,
                  progress: bool = False) -> None:
         # Missing values are reported by check_params()
@@ -228,8 +229,9 @@ class Backup:
         self._inputs_path = ''
         self._exclude_path = ''
         self._remote = False
-        self._ssh: Optional[paramiko.client.SSHClient] = None
-        self._password_auth = False
+        self._ssh: paramiko.client.SSHClient | None = None
+        # Passed to sshpass through rsync's environment only
+        self._password: str | None = None
         self._removed_count = 0
 
     def check_params(self, homedir: str = '') -> int:
@@ -281,7 +283,7 @@ class Backup:
 
         return 0
 
-    def _resolve_remote_path(self, path: str) -> Optional[str]:
+    def _resolve_remote_path(self, path: str) -> str | None:
         """Return the absolute path of a directory on the server, or None if it doesn't exist"""
 
         assert self._ssh is not None
@@ -313,9 +315,50 @@ class Backup:
         if self._remote:
             self._server = f'{self.ssh_user}@{self.ssh_host}:'
 
+    @property
+    def destination(self) -> str:
+        """The current backup directory, prefixed with 'user@host:' for remote backups"""
+
+        return f'{self._server}{self._output_dir}'
+
     def remove_old_backups(self) -> None:
         """Remove old backups if there are more than indicated by 'keep'"""
 
+        dirs = self._list_backups()
+
+        if dirs is None:
+            return
+
+        n_backup = len(dirs)
+
+        # The new backup is already in the list, unless old ones are removed before it
+        if not self._remove_before:
+            n_backup -= 1
+
+        count = 0
+
+        if n_backup > self.keep:
+            logger.info('Removing old backups...')
+            dirs.sort()
+
+            n_remove = n_backup - self.keep
+
+            for i in range(n_remove):
+                logger.info('Removing backup %s (%d/%d)...', dirs[i], i + 1, n_remove)
+
+                if self._remove_backup(dirs[i]):
+                    count += 1
+
+        self._removed_count = count
+
+        if count == 1:
+            logger.info('Removed %d backup', count)
+        elif count > 1:
+            logger.info('Removed %d backups', count)
+
+    def _list_backups(self) -> list[str] | None:
+        """Names of the backup directories, or None if they can't be listed (then nothing is removed)"""
+
         if self._remote:
             assert self._ssh is not None
 
@@ -333,85 +376,54 @@ class Backup:
                 logger.error('Cannot list old backups on the server. Old backups will not be removed')
                 logger.error(err)
 
-                return
+                return None
 
-            dirs = [os.path.basename(d) for d in output.split('\n') if d != '']
+            return [os.path.basename(d) for d in output.split('\n') if d != '']
 
-            n_backup = len(dirs)
+        try:
+            # Only count directories, so that stray files don't count as backups
+            return [f.name for f in os.scandir(f'{self.output}/simple_backup') if f.is_dir(follow_symlinks=False)]
+        except FileNotFoundError:
+            return None
+        except PermissionError:
+            logger.error('Cannot list old backups. Permission denied. Old backups will not be removed')
 
-            if not self._remove_before:
-                n_backup -= 1
+            return None
 
-            count = 0
+    def _remove_backup(self, name: str) -> bool:
+        """Remove one backup directory; errors are logged"""
 
-            if n_backup > self.keep:
-                logger.info('Removing old backups...')
-                dirs.sort()
+        path = f'{self.output}/simple_backup/{name}'
 
-                n_remove = n_backup - self.keep
+        if self._remote:
+            assert self._ssh is not None
 
-                for i in range(n_remove):
-                    logger.info('Removing backup %s (%d/%d)...', dirs[i], i + 1, n_remove)
+            sudo = 'sudo ' if self.remote_sudo else ''
+            _, _, stderr = self._ssh.exec_command(f'{sudo}rm -r {shlex.quote(path)}')
 
-                    if self.remote_sudo:
-                        _, _, stderr = self._ssh.exec_command(
-                            f'sudo rm -r {shlex.quote(f"{self.output}/simple_backup/{dirs[i]}")}')
-                    else:
-                        _, _, stderr = self._ssh.exec_command(
-                            f'rm -r {shlex.quote(f"{self.output}/simple_backup/{dirs[i]}")}')
+            err = stderr.read().decode('utf-8').strip().split('\n')[0]
 
-                    err = stderr.read().decode('utf-8').strip().split('\n')[0]
+            if err != '':
+                logger.error('Error while removing backup %s.', name)
+                logger.error(err)
 
-                    if err != '':
-                        logger.error(
-                            'Error while removing backup %s.', dirs[i])
-                        logger.error(err)
-                    else:
-                        count += 1
-        else:
-            try:
-                # Only count directories, so that stray files don't count as backups
-                dirs = [f.name for f in os.scandir(f'{self.output}/simple_backup')
-                        if f.is_dir(follow_symlinks=False)]
-            except FileNotFoundError:
-                return
-            except PermissionError:
-                logger.error('Cannot list old backups. Permission denied. Old backups will not be removed')
+                return False
 
-                return
+            return True
 
-            n_backup = len(dirs)
+        try:
+            rmtree(path)
 
-            if not self._remove_before:
-                n_backup -= 1
+            return True
+        except FileNotFoundError:
+            logger.error('Error while removing backup %s. Directory not found', name)
+        except PermissionError:
+            logger.error('Error while removing backup %s. Permission denied', name)
+        except OSError as e:
+            # E.g. read-only filesystem or device busy
+            logger.error('Error while removing backup %s. %s', name, e.strerror or e)
 
-            count = 0
-
-            if n_backup > self.keep:
-                logger.info('Removing old backups...')
-                dirs.sort()
-
-                n_remove = n_backup - self.keep
-
-                for i in range(n_remove):
-                    logger.info('Removing backup %s (%d/%d)...', dirs[i], i + 1, n_remove)
-
-                    try:
-                        rmtree(f'{self.output}/simple_backup/{dirs[i]}')
-                        count += 1
-                    except FileNotFoundError:
-                        logger.error(
-                            'Error while removing backup %s. Directory not found', dirs[i])
-                    except PermissionError:
-                        logger.error(
-                            'Error while removing backup %s. Permission denied', dirs[i])
-
-        self._removed_count = count
-
-        if count == 1:
-            logger.info('Removed %d backup', count)
-        elif count > 1:
-            logger.info('Removed %d backups', count)
+        return False
 
     def find_last_backup(self) -> None:
         """Get path of last backup (from last_backup symlink) for rsync --link-dest"""
@@ -450,7 +462,7 @@ class Backup:
             except IndexError:
                 logger.info('No previous backups available')
 
-    def _ssh_connect(self, homedir: str = '') -> Optional[paramiko.client.SSHClient]:
+    def _ssh_connect(self, homedir: str = '') -> paramiko.client.SSHClient | None:
         try:
             ssh = paramiko.SSHClient()
         except NameError:
@@ -469,7 +481,37 @@ class Backup:
             if connected is None:
                 ssh.close()
 
-    def _ssh_login(self, ssh: paramiko.client.SSHClient, homedir: str) -> Optional[paramiko.client.SSHClient]:
+    def _ssh_config(self, homedir: str) -> dict[str, Any]:
+        """connect() arguments for ssh_host from ~/.ssh/config (HostName, Port, IdentityFile), as rsync's ssh uses it"""
+
+        assert self.ssh_host is not None
+
+        params: dict[str, Any] = {'hostname': self.ssh_host}
+
+        try:
+            host = paramiko.SSHConfig.from_path(f'{homedir}/.ssh/config').lookup(self.ssh_host)
+
+            params['hostname'] = host['hostname']
+
+            if 'port' in host:
+                params['port'] = int(host['port'])
+        except FileNotFoundError:
+            return params
+        except (OSError, paramiko.SSHException, ImportError, ValueError) as e:
+            # ImportError: 'Match exec' needs the invoke module
+            logger.warning('Cannot read %s/.ssh/config: %s', homedir, e)
+
+            return {'hostname': self.ssh_host}
+
+        # Like ssh, skip identity files that don't exist
+        keys = [k for k in host.get('identityfile', []) if os.path.isfile(k)]
+
+        if keys:
+            params['key_filename'] = keys
+
+        return params
+
+    def _ssh_login(self, ssh: paramiko.client.SSHClient, homedir: str) -> paramiko.client.SSHClient | None:
         try:
             ssh.load_host_keys(filename=f'{homedir}/.ssh/known_hosts')
         except FileNotFoundError:
@@ -477,11 +519,13 @@ class Backup:
 
         ssh.set_missing_host_key_policy(paramiko.WarningPolicy())
 
+        host = self._ssh_config(homedir)
+
         try:
             # WarningPolicy emits a UserWarning for unknown host keys
             with warnings.catch_warnings():
                 warnings.simplefilter('error', UserWarning)
-                ssh.connect(self.ssh_host, username=self.ssh_user, timeout=SSH_TIMEOUT)
+                ssh.connect(**host, username=self.ssh_user, timeout=SSH_TIMEOUT)
 
             return ssh
         except UserWarning:
@@ -507,7 +551,7 @@ class Backup:
             pass
 
         try:
-            ssh.connect(self.ssh_host, username=self.ssh_user, timeout=SSH_TIMEOUT)
+            ssh.connect(**host, username=self.ssh_user, timeout=SSH_TIMEOUT)
 
             return ssh
         except paramiko.SSHException:
@@ -521,11 +565,9 @@ class Backup:
                     password = getpass(
                         f'{self.ssh_user}@{self.ssh_host}\'s password: ')
 
-                ssh.connect(self.ssh_host, username=self.ssh_user, timeout=SSH_TIMEOUT,
-                            password=password)
+                ssh.connect(**host, username=self.ssh_user, timeout=SSH_TIMEOUT, password=password)
 
-                self._password_auth = True
-                os.environ['SSHPASS'] = password
+                self._password = password
 
                 return ssh
             except GetPassWarning as e:
@@ -545,7 +587,7 @@ class Backup:
             return None
 
         try:
-            ssh.connect(self.ssh_host, username=self.ssh_user, timeout=SSH_TIMEOUT, pkey=pkey)
+            ssh.connect(**host, username=self.ssh_user, timeout=SSH_TIMEOUT, pkey=pkey)
         except paramiko.SSHException:
             logger.critical('SSH connection to server failed')
 
@@ -553,7 +595,7 @@ class Backup:
 
         return ssh
 
-    def _load_ssh_key(self) -> Optional[paramiko.PKey]:
+    def _load_ssh_key(self) -> paramiko.PKey | None:
         try:
             return paramiko.PKey.from_path(self.ssh_keyfile)
         except TypeError:
@@ -656,6 +698,16 @@ class Backup:
 
         _notify('Starting backup...')
 
+        # Check before anything is removed (--remove-before-backup)
+        rsync = which('rsync')
+
+        if rsync is None:
+            logger.critical('rsync not found. Install rsync to perform the backup')
+
+            _notify('Backup failed (check log for details)')
+
+            return 4
+
         self.define_backup_dir()
 
         fd, self._inputs_path = mkstemp(prefix='tmp_inputs', text=True)
@@ -695,7 +747,7 @@ class Backup:
         logger.info('Copying files. This may take a long time...')
 
         # Build the argument list directly, so paths with spaces or quotes are passed unchanged
-        args = ['/usr/bin/rsync', *self.options.split()]
+        args = [rsync, *self.options.split()]
 
         if self._last_backup != '':
             args.append(f'--link-dest={self._last_backup}')
@@ -703,11 +755,15 @@ class Backup:
         args.extend([f'--exclude-from={self._exclude_path}', f'--files-from={self._inputs_path}',
                      '/', f'{self._server}{self._output_dir}'])
 
+        # None inherits our environment
+        env: dict[str, str] | None = None
+
         # rsync splits the -e command itself, so quote the parts that may contain spaces
         if self.ssh_keyfile is not None:
             ssh = f'ssh -i {shlex.quote(self.ssh_keyfile)} -o StrictHostKeyChecking=accept-new'
-        elif self._password_auth and self.ssh_user is not None and which('sshpass'):
+        elif self._password is not None and self.ssh_user is not None and which('sshpass'):
             ssh = f'sshpass -e ssh -l {shlex.quote(self.ssh_user)} -o StrictHostKeyChecking=accept-new'
+            env = {**os.environ, 'SSHPASS': self._password}
         else:
             ssh = 'ssh -o StrictHostKeyChecking=accept-new'
 
@@ -722,11 +778,12 @@ class Backup:
             args.append('--info=progress2')
             bar = _ProgressBar()
 
-        with Popen(args, stdin=PIPE, stdout=PIPE, stderr=STDOUT, shell=False) as p:
+        with Popen(args, stdin=PIPE, stdout=PIPE, stderr=STDOUT, shell=False, env=env) as p:
             assert p.stdin is not None and isinstance(p.stdout, io.BufferedIOBase)
             p.stdin.close()
 
-            output = []
+            # Without -v, only the summary (the last two lines) is logged
+            output: list[str] | deque[str] = [] if self._verbose else deque(maxlen=2)
 
             try:
                 for r in _read_records(p.stdout):
@@ -736,27 +793,20 @@ class Backup:
                 if bar is not None:
                     bar.clear()
 
-            try:
-                del os.environ['SSHPASS']
-            except KeyError:
-                pass
-
             returncode = p.wait()
 
         if returncode == 0:
-            if self._verbose:
-                logger.info('rsync: %s', output)
-            else:
-                logger.info('rsync: %s', output[-2])
-                logger.info('rsync: %s', output[-1])
+            # Without -v, only the summary, which may be fewer than two lines (e.g. with --rsync-options q)
+            for r in output:
+                logger.info('rsync: %s', r)
         else:
             self._returncode_log(returncode)
 
             if self._verbose:
-                if returncode in [23, 24]:
-                    logger.warning(output)
-                else:
-                    logger.error(output)
+                level = logging.WARNING if returncode in [23, 24] else logging.ERROR
+
+                for r in output:
+                    logger.log(level, 'rsync: %s', r)
 
         if self._removed_count > 0 and returncode not in [0, 24]:
             # With --remove-before-backup, old backups are already gone if the new one failed
@@ -808,7 +858,7 @@ def _read_records(stream: io.BufferedIOBase) -> Iterator[str]:
         yield buffer.decode('utf-8', errors='replace')
 
 
-def _detect_user() -> Optional[str]:
+def _detect_user() -> str | None:
     if os.geteuid() == 0:
         return os.getenv('SUDO_USER') or os.getenv('DOAS_USER')
 
@@ -858,6 +908,8 @@ def _parse_arguments() -> argparse.Namespace:
                         help='Run rsync on remote server with sudo if allowed')
     parser.add_argument('--numeric-ids', action='store_true',
                         help='Use rsync \'--numeric-ids\' option (don\'t map uid/gid values by name)')
+    parser.add_argument('--last-backup', action='store_true',
+                        help='Show when the last successful backup was made and exit')
 
     args = parser.parse_args()
 
@@ -873,21 +925,24 @@ def _expand_home(path: str, user: str) -> str:
     return os.path.expanduser(path)
 
 
-def _expand_inputs(inputs: List[str], user: Optional[str] = None) -> List[str]:
-    expanded_inputs: List[str] = []
+def _expand_inputs(inputs: list[str], user: str | None = None) -> list[str]:
+    expanded_inputs: list[str] = []
 
     for i in inputs:
         if i == '':
             continue
 
         if user is not None:
-            i_ex = glob(_expand_home(i, user))
+            path = _expand_home(i, user)
         else:
-            i_ex = glob(i)
+            path = i
 
             if i.startswith('~'):
                 logger.warning('Cannot expand \'~\'. No user specified')
 
+        # An existing path is used as is, so names with glob characters (e.g. 'Photos [2020]') still work
+        i_ex = [path] if os.path.lexists(path) else glob(path)
+
         if len(i_ex) == 0:
             logger.warning(
                 'No file or directory matching input %s. Skipping...', i)
@@ -900,13 +955,13 @@ def _expand_inputs(inputs: List[str], user: Optional[str] = None) -> List[str]:
 class ConfigArgs(TypedDict):
     """Values read from the configuration file"""
 
-    inputs: Optional[List[str]]
-    output: Optional[str]
-    exclude: Optional[List[str]]
+    inputs: list[str] | None
+    output: str | None
+    exclude: list[str] | None
     keep: int
-    ssh_host: Optional[str]
-    ssh_user: Optional[str]
-    ssh_keyfile: Optional[str]
+    ssh_host: str | None
+    ssh_user: str | None
+    ssh_keyfile: str | None
     remote_sudo: bool
     numeric_ids: bool
 
@@ -919,7 +974,7 @@ def _get_bool(config: configparser.ConfigParser, key: str) -> bool:
     return config.getboolean('server', key)
 
 
-def _read_config(config_file: str, user: Optional[str] = None) -> ConfigArgs:
+def _read_config(config_file: str, user: str | None = None) -> ConfigArgs:
     config_args: ConfigArgs = {'inputs': None,
                                'output': None,
                                'exclude': None,
@@ -943,19 +998,22 @@ def _read_config(config_file: str, user: Optional[str] = None) -> ConfigArgs:
     config = configparser.ConfigParser(interpolation=None)
     config.read(config_file)
 
-    section = 'backup'
-
     # Allow compatibility with previous version of config file
-    try:
-        inputs = config.get(section, 'inputs')
-    except configparser.NoSectionError:
+    if config.has_section('backup'):
+        section = 'backup'
+    elif config.has_section('default'):
         section = 'default'
-        inputs = config.get(section, 'inputs')
+    else:
+        raise configparser.NoSectionError('backup')
 
-    config_args['inputs'] = list(set(_expand_inputs([i.strip() for i in inputs.split(',')], user)))
+    # inputs and backup_dir are optional, since -i and -o can give them. Missing ones are reported by check_params()
+    inputs = config.get(section, 'inputs', fallback=None)
+
+    if inputs is not None:
+        config_args['inputs'] = list(set(_expand_inputs([i.strip() for i in inputs.split(',')], user)))
 
     # '~' is expanded later, since for remote backups it refers to the home on the server
-    config_args['output'] = config.get(section, 'backup_dir')
+    config_args['output'] = config.get(section, 'backup_dir', fallback=None)
 
     exclude = config.get(section, 'exclude', fallback='')
     config_args['exclude'] = [e.strip() for e in exclude.split(',') if e.strip() != '']
@@ -1027,31 +1085,119 @@ def _notify(text: str) -> None:
         os.seteuid(euid)
 
 
+def _state_owner(user: str | None) -> pwd.struct_passwd | None:
+    """The user whose state file is used when running as root on their behalf (sudo, doas, -u)"""
+
+    if os.geteuid() != 0 or user is None:
+        return None
+
+    try:
+        owner = pwd.getpwnam(user)
+    except KeyError:
+        return None
+
+    return owner if owner.pw_uid != 0 else None
+
+
+def _state_file(owner: pwd.struct_passwd | None) -> str:
+    if owner is not None:
+        # XDG_STATE_HOME belongs to root here
+        base = os.path.join(owner.pw_dir, '.local', 'state')
+    else:
+        base = os.getenv('XDG_STATE_HOME', '')
+
+        # The XDG spec says to ignore relative paths
+        if not os.path.isabs(base):
+            base = os.path.expanduser('~/.local/state')
+
+    return os.path.join(base, 'simple_backup', 'last_backup')
+
+
+def _write_state(user: str | None, destination: str) -> None:
+    """Record the time and directory of the last successful backup (two lines)"""
+
+    owner = _state_owner(user)
+    path = _state_file(owner)
+    tmp = ''
+    euid, egid = os.geteuid(), os.getegid()
+
+    # Create the file (and any missing directories) as the user, not root
+    if owner is not None:
+        os.setegid(owner.pw_gid)
+        os.seteuid(owner.pw_uid)
+
+    try:
+        os.makedirs(os.path.dirname(path), exist_ok=True)
+
+        # Replace the file in one step, so readers (e.g. status bar scripts) never see it half written
+        fd, tmp = mkstemp(prefix='.last_backup', dir=os.path.dirname(path), text=True)
+
+        with os.fdopen(fd, 'w', encoding='utf-8') as fp:
+            fp.write(f'{datetime.now().astimezone().isoformat(timespec="seconds")}\n{destination}\n')
+
+        os.replace(tmp, path)
+    except OSError as e:
+        logger.warning('Cannot save the time of the last backup to %s: %s', path, e)
+
+        if tmp != '':
+            try:
+                os.remove(tmp)
+            except OSError:
+                pass
+    finally:
+        if owner is not None:
+            os.seteuid(euid)
+            os.setegid(egid)
+
+
+def _show_last_backup(user: str | None) -> int:
+    path = _state_file(_state_owner(user))
+
+    try:
+        with open(path, encoding='utf-8') as fp:
+            time, destination = fp.read().splitlines()[:2]
+
+        completed = datetime.fromisoformat(time).astimezone()
+    except FileNotFoundError:
+        print('No backup recorded yet')
+
+        return 1
+    except (OSError, ValueError) as e:
+        print(f'Cannot read {path}: {e}', file=sys.stderr)
+
+        return 1
+
+    days = (datetime.now().astimezone().date() - completed.date()).days
+
+    if days == 0:
+        age = 'today'
+    elif days == 1:
+        age = 'yesterday'
+    else:
+        age = f'{days} days ago'
+
+    print(f'Last backup: {completed:%Y-%m-%d %H:%M} ({age})')
+    print(f'Directory: {destination}')
+
+    return 0
+
+
 def simple_backup() -> int:
     """Main"""
 
     args = _parse_arguments()
 
-    if args.user:
-        user = args.user
-        homedir = os.path.expanduser(f'~{user}')
+    user: str | None = args.user or _detect_user()
+
+    if args.last_backup:
+        return _show_last_backup(user)
+
+    if not args.user and os.geteuid() != 0:
+        homedir = os.getenv('HOME', '')
+    elif user is not None:
+        homedir = _expand_home('~', user)
     else:
-        euid = os.geteuid()
-
-        if euid == 0:
-            user = _detect_user()
-
-            if user is not None:
-                homedir = os.path.expanduser(f'~{user}')
-            else:
-                logger.warning(
-                    'Failed to detect user. You can use -u/--user parameter to manually specify it')
-                homedir = None
-        else:
-            user = os.getenv('USER')
-            homedir = os.getenv('HOME')
-
-    if homedir is None:
+        logger.warning('Failed to detect user. You can use -u/--user parameter to manually specify it')
         homedir = ''
 
     if args.no_syslog:
@@ -1060,13 +1206,8 @@ def simple_backup() -> int:
         except NameError:
             pass
 
-    config_file = args.config
-
     # Expand '~' to the home of the user running the backup, not root's
-    if config_file.startswith('~/') and user is not None:
-        config_file = f'~{user}{config_file[1:]}'
-
-    config_file = os.path.expanduser(config_file)
+    config_file = _expand_home(args.config, user) if user is not None else os.path.expanduser(args.config)
 
     try:
         config_args = _read_config(config_file, user)
@@ -1082,6 +1223,11 @@ def simple_backup() -> int:
     ssh_host = args.ssh_host if args.ssh_host is not None else config_args['ssh_host']
     ssh_user = args.ssh_user if args.ssh_user is not None else config_args['ssh_user']
 
+    if keep < -1:
+        logger.critical('Invalid number of backups to keep: %d (use -1 to keep all)', keep)
+
+        return 6
+
     if (ssh_host is None) != (ssh_user is None):
         logger.critical('Both SSH host and SSH user are needed for remote backup')
 
@@ -1129,8 +1275,13 @@ def simple_backup() -> int:
     try:
         return_code = backup.check_params(homedir)
 
+        if return_code != 0:
+            return return_code
+
+        return_code = backup.run()
+
         if return_code == 0:
-            return backup.run()
+            _write_state(user, backup.destination)
 
         return return_code
     finally:
@@ -1138,4 +1289,4 @@ def simple_backup() -> int:
 
 
 if __name__ == '__main__':
-    simple_backup()
+    sys.exit(simple_backup())

tests/conftest.py

@@ -1,7 +1,9 @@
 """Shared fixtures for the simple_backup tests"""
 
 import sys
-from typing import Callable
+from collections.abc import Callable, Iterator
+from datetime import datetime, timedelta
+from pathlib import Path
 
 import pytest
 
@@ -9,13 +11,35 @@ from simple_backup import simple_backup as sb
 
 
 @pytest.fixture(autouse=True)
-def no_side_effects(monkeypatch: pytest.MonkeyPatch) -> None:
-    """Keep tests out of the systemd journal and the desktop notifications"""
+def no_side_effects(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+    """Keep tests out of the systemd journal, the desktop notifications and the user's state directory"""
 
     if hasattr(sb, 'j_handler'):
         sb.logger.removeHandler(sb.j_handler)
 
     monkeypatch.setattr(sb, '_notify', lambda text: None)
+    monkeypatch.setenv('XDG_STATE_HOME', str(tmp_path / 'state'))
+
+
+@pytest.fixture
+def fake_now(monkeypatch: pytest.MonkeyPatch) -> None:
+    """Give each backup a new timestamp, as real runs within the same second would collide"""
+
+    def times() -> Iterator[datetime]:
+        t = datetime(2026, 10, 14, 10, 0, 0)
+
+        while True:
+            yield t
+            t += timedelta(hours=1)
+
+    it = times()
+
+    class FakeDatetime:
+        @staticmethod
+        def now() -> datetime:
+            return next(it)
+
+    monkeypatch.setattr(sb, 'datetime', FakeDatetime)
 
 
 @pytest.fixture

tests/test_cli.py

@@ -2,8 +2,11 @@
 
 import os
 import pwd
+import subprocess
+import sys
+from collections.abc import Callable
 from pathlib import Path
-from typing import Any, Callable, Optional
+from typing import Any
 
 import pytest
 
@@ -23,10 +26,12 @@ class FakeBackup:
 
     instances: list['FakeBackup'] = []
     check_code = 0
+    run_code = 0
+    destination = '/backups/simple_backup/2026-10-25_10-00-00'
 
     def __init__(self, inputs: Any, output: Any, exclude: Any, keep: Any, options: str,
-                 ssh_host: Optional[str] = None, ssh_user: Optional[str] = None,
-                 ssh_keyfile: Optional[str] = None, remote_sudo: bool = False,
+                 ssh_host: str | None = None, ssh_user: str | None = None,
+                 ssh_keyfile: str | None = None, remote_sudo: bool = False,
                  remove_before: bool = False, verbose: bool = False, progress: bool = False) -> None:
         self.inputs = inputs
         self.output = output
@@ -40,7 +45,7 @@ class FakeBackup:
         self.remove_before = remove_before
         self.verbose = verbose
         self.progress = progress
-        self.homedir: Optional[str] = None
+        self.homedir: str | None = None
         self.ran = False
         self.closed = False
         FakeBackup.instances.append(self)
@@ -53,7 +58,7 @@ class FakeBackup:
     def run(self) -> int:
         self.ran = True
 
-        return 0
+        return FakeBackup.run_code
 
     def close(self) -> None:
         self.closed = True
@@ -63,6 +68,7 @@ class FakeBackup:
 def fake_backup(monkeypatch: pytest.MonkeyPatch) -> None:
     FakeBackup.instances = []
     FakeBackup.check_code = 0
+    FakeBackup.run_code = 0
     monkeypatch.setattr(sb, 'Backup', FakeBackup)
 
 
@@ -80,19 +86,21 @@ def as_root(monkeypatch: pytest.MonkeyPatch) -> None:
     """Run as root, with no sudo/doas variables set"""
 
     monkeypatch.setattr(os, 'geteuid', lambda: 0)
+    # Writing the state file as root would call seteuid() (covered in test_state.py)
+    monkeypatch.setattr(sb, '_write_state', lambda user, destination: None)
 
     for var in ['SUDO_USER', 'SUDO_UID', 'DOAS_USER']:
         monkeypatch.delenv(var, raising=False)
 
 
 @pytest.fixture
-def config_calls(monkeypatch: pytest.MonkeyPatch) -> list[tuple[str, Optional[str]]]:
+def config_calls(monkeypatch: pytest.MonkeyPatch) -> list[tuple[str, str | None]]:
     """Record the config file path and user instead of reading the file"""
 
-    calls: list[tuple[str, Optional[str]]] = []
+    calls: list[tuple[str, str | None]] = []
     read_config = sb._read_config
 
-    def record(config_file: str, user: Optional[str] = None) -> sb.ConfigArgs:
+    def record(config_file: str, user: str | None = None) -> sb.ConfigArgs:
         calls.append((config_file, user))
 
         return read_config('/nonexistent/simple_backup.conf', user)
@@ -169,6 +177,15 @@ ssh_keyfile=/keys/id
         assert b.keep == 0
         assert (b.ssh_host, b.ssh_user, b.ssh_keyfile) == ('cli-host', 'cli-user', '/cli/key')
 
+    def test_inputs_and_output_only_from_cli(self, run_cli: RunCli, tmp_path: Path) -> None:
+        config_file = tmp_path / 'simple_backup.conf'
+        config_file.write_text('[backup]\nkeep=3\n')
+
+        assert run_cli('-c', str(config_file), '-i', '/cli/in', '-o', '/cli/out') == 0
+
+        b = last_backup()
+        assert (b.inputs, b.output, b.keep) == (['/cli/in'], '/cli/out', 3)
+
     def test_ssh_host_and_user_from_cli_and_config(self, run_cli: RunCli, config: Callable[[str], str]) -> None:
         config_file = config('backup_dir=/backups\n[server]\nssh_user=user')
 
@@ -190,6 +207,18 @@ ssh_keyfile=/keys/id
         assert FakeBackup.instances == []
         assert 'Both SSH host and SSH user are needed' in caplog.text
 
+    @pytest.mark.parametrize('config_keep, argv', [
+        ('keep=-2', []),
+        ('', ['-k', '-2']),
+    ])
+    def test_keep_below_minus_one(self, run_cli: RunCli, config: Callable[[str], str],
+                                  caplog: pytest.LogCaptureFixture, config_keep: str, argv: list[str]) -> None:
+        config_file = config(f'backup_dir=/backups\n{config_keep}')
+
+        assert run_cli('-c', config_file, *argv) == 6
+        assert FakeBackup.instances == []
+        assert 'Invalid number of backups to keep: -2' in caplog.text
+
     def test_bad_config(self, run_cli: RunCli, config: Callable[[str], str],
                         caplog: pytest.LogCaptureFixture) -> None:
         config_file = config('backup_dir=/backups\nkeep=abc')
@@ -246,23 +275,37 @@ ssh_keyfile=/keys/id
         assert not b.ran
         assert b.closed
 
+    @pytest.mark.parametrize('check_code, run_code, saved', [(0, 0, True), (2, 0, False), (0, 4, False)])
+    def test_state_saved_only_on_success(self, run_cli: RunCli, config: Callable[[str], str], tmp_path: Path,
+                                         check_code: int, run_code: int, saved: bool) -> None:
+        FakeBackup.check_code = check_code
+        FakeBackup.run_code = run_code
+
+        assert run_cli('-c', config('backup_dir=/backups')) == (check_code or run_code)
+
+        state = tmp_path / 'state' / 'simple_backup' / 'last_backup'
+        assert state.exists() is saved
+
+        if saved:
+            assert state.read_text().splitlines()[1] == FakeBackup.destination
+
 
 class TestUser:
     @pytest.mark.usefixtures('as_user')
-    def test_current_user(self, run_cli: RunCli, config_calls: list[tuple[str, Optional[str]]]) -> None:
+    def test_current_user(self, run_cli: RunCli, config_calls: list[tuple[str, str | None]]) -> None:
         assert run_cli() == 0
         assert config_calls == [(f'{HOME}/.config/simple_backup/simple_backup.conf', USER)]
         assert last_backup().homedir == HOME
 
     @pytest.mark.usefixtures('as_root')
-    def test_explicit_user(self, run_cli: RunCli, config_calls: list[tuple[str, Optional[str]]]) -> None:
+    def test_explicit_user(self, run_cli: RunCli, config_calls: list[tuple[str, str | None]]) -> None:
         assert run_cli('-u', USER, '-c', '~/other.conf') == 0
         assert config_calls == [(f'{HOME}/other.conf', USER)]
         assert last_backup().homedir == HOME
 
     @pytest.mark.usefixtures('as_root')
     @pytest.mark.parametrize('var', ['SUDO_USER', 'DOAS_USER'])
-    def test_sudo_or_doas_user(self, run_cli: RunCli, config_calls: list[tuple[str, Optional[str]]],
+    def test_sudo_or_doas_user(self, run_cli: RunCli, config_calls: list[tuple[str, str | None]],
                                monkeypatch: pytest.MonkeyPatch, var: str) -> None:
         monkeypatch.setenv(var, USER)
 
@@ -271,7 +314,7 @@ class TestUser:
         assert last_backup().homedir == HOME
 
     @pytest.mark.usefixtures('as_root')
-    def test_root_without_user(self, run_cli: RunCli, config_calls: list[tuple[str, Optional[str]]],
+    def test_root_without_user(self, run_cli: RunCli, config_calls: list[tuple[str, str | None]],
                                caplog: pytest.LogCaptureFixture) -> None:
         assert run_cli() == 0
         # '~' is left to expanduser, i.e. $HOME
@@ -303,6 +346,20 @@ class TestDetectUser:
         assert sb._detect_user() == USER
 
 
+def test_run_as_script(tmp_path: Path) -> None:
+    """Running the module directly passes simple_backup()'s return code to the shell"""
+
+    repo = Path(sb.__file__).resolve().parents[1]
+    env = {**os.environ, 'PYTHONPATH': str(repo), 'HOME': str(tmp_path)}
+
+    # No config file and no inputs: check_params() returns 1
+    result = subprocess.run([sys.executable, '-m', 'simple_backup.simple_backup', '--no-syslog',
+                             '-c', str(tmp_path / 'missing.conf')], env=env, cwd=tmp_path,
+                            capture_output=True, check=False)
+
+    assert result.returncode == 1
+
+
 class TestTargetUid:
     @pytest.mark.usefixtures('as_user')
     def test_non_root(self) -> None:

tests/test_config.py

@@ -45,6 +45,13 @@ def test_expand_inputs_glob(tmp_path: Path) -> None:
     assert sorted(result) == [f'{tmp_path}/a.txt', f'{tmp_path}/b.txt']
 
 
+def test_expand_inputs_glob_characters_in_name(tmp_path: Path) -> None:
+    (tmp_path / 'Photos [2020]').mkdir()
+    (tmp_path / 'Photos 2').mkdir()
+
+    assert sb._expand_inputs([f'{tmp_path}/Photos [2020]'], USER) == [f'{tmp_path}/Photos [2020]']
+
+
 def test_expand_inputs_no_match(tmp_path: Path, caplog: pytest.LogCaptureFixture) -> None:
     assert sb._expand_inputs([f'{tmp_path}/missing'], USER) == []
     assert 'No file or directory matching input' in caplog.text
@@ -217,9 +224,15 @@ backup_dir=/backups
         sb._read_config(config_file, USER)
 
 
+def test_inputs_and_backup_dir_optional(tmp_path: Path) -> None:
+    config_args = sb._read_config(write_config(tmp_path, '[backup]\nkeep=2\n'), USER)
+
+    assert config_args['inputs'] is None
+    assert config_args['output'] is None
+    assert config_args['keep'] == 2
+
+
 @pytest.mark.parametrize('text', [
-    '[backup]\nbackup_dir=/backups\n',
-    '[backup]\ninputs=/tmp\n',
     '[other]\ninputs=/tmp\n',
     'inputs=/tmp\n',
 ])

tests/test_local.py

@@ -1,10 +1,12 @@
 """Tests for local backups, with real rsync runs and with a fake Popen"""
 
+import errno
 import io
 import os
-from datetime import datetime, timedelta
+from collections.abc import Callable
 from pathlib import Path
-from typing import Any, Callable, Iterator, Optional
+from shutil import which
+from typing import Any
 
 import pytest
 
@@ -13,25 +15,7 @@ from simple_backup import simple_backup as sb
 OPTIONS = '-r -v --ignore-missing-args --mkpath -a -h -H -X -s'
 
 
-@pytest.fixture(autouse=True)
-def fake_now(monkeypatch: pytest.MonkeyPatch) -> None:
-    """Give each backup a new timestamp, as real runs within the same second would collide"""
-
-    def times() -> Iterator[datetime]:
-        t = datetime(2026, 10, 14, 10, 0, 0)
-
-        while True:
-            yield t
-            t += timedelta(hours=1)
-
-    it = times()
-
-    class FakeDatetime:
-        @staticmethod
-        def now() -> datetime:
-            return next(it)
-
-    monkeypatch.setattr(sb, 'datetime', FakeDatetime)
+pytestmark = pytest.mark.usefixtures('fake_now')
 
 
 @pytest.fixture
@@ -52,10 +36,10 @@ def out(tmp_path: Path) -> Path:
     return out
 
 
-def make_backup(out: Path, inputs: list[str], keep: int = -1, exclude: Optional[list[str]] = None,
-                remove_before: bool = False, progress: bool = False) -> sb.Backup:
+def make_backup(out: Path, inputs: list[str], keep: int = -1, exclude: list[str] | None = None,
+                remove_before: bool = False, progress: bool = False, verbose: bool = False) -> sb.Backup:
     backup = sb.Backup(inputs, str(out), exclude or [], keep, OPTIONS, remove_before=remove_before,
-                       progress=progress)
+                       progress=progress, verbose=verbose)
 
     assert backup.check_params() == 0
 
@@ -160,6 +144,19 @@ class TestRsync:
         # Nothing to link against, as the old backup was removed first
         assert copied(out, backup, src / 'same.txt').stat().st_nlink == 1
 
+    def test_removal_os_error(self, src: Path, out: Path, monkeypatch: pytest.MonkeyPatch,
+                              caplog: pytest.LogCaptureFixture) -> None:
+        assert run_backup(out, [str(src)]) == 0
+
+        def busy(path: str) -> None:
+            raise OSError(errno.EBUSY, os.strerror(errno.EBUSY), path)
+
+        monkeypatch.setattr(sb, 'rmtree', busy)
+
+        assert run_backup(out, [str(src)], keep=0) == 0
+        assert backups(out) == ['2026-10-14_10-00-00', '2026-10-14_11-00-00']
+        assert 'Error while removing backup 2026-10-14_10-00-00. Device or resource busy' in caplog.text
+
     def test_stray_files_and_symlinks(self, src: Path, out: Path) -> None:
         assert run_backup(out, [str(src)]) == 0
 
@@ -204,7 +201,11 @@ class TestRsync:
         for _ in range(2):
             assert run_cli('-c', config_file, '-i', str(src), '-o', str(out), '-k', '0') == 0
 
-        assert backups(out) == ['2026-10-14_11-00-00']
+        # The fake clock also advances when the state file is written
+        assert backups(out) == ['2026-10-14_12-00-00']
+        state = (tmp_path / 'state' / 'simple_backup' / 'last_backup').read_text().splitlines()
+        assert state[0].startswith('2026-10-14T13:00:00')
+        assert state[1] == f'{out}/simple_backup/2026-10-14_12-00-00'
 
 
 class ChunkStream(io.BufferedIOBase):
@@ -282,12 +283,13 @@ class FakePopen:
 
     returncode = 0
     calls: list[list[str]] = []
+    output = b'sending incremental file list\nsent 1 bytes  received 2 bytes\ntotal size is 3\n'
 
     def __init__(self, args: list[str], **kwargs: Any) -> None:
         FakePopen.calls.append(args)
         os.makedirs(args[args.index('/') + 1])
         self.stdin = io.BytesIO()
-        self.stdout = io.BytesIO(b'sending incremental file list\nsent 1 bytes  received 2 bytes\ntotal size is 3\n')
+        self.stdout = io.BytesIO(FakePopen.output)
 
     def __enter__(self) -> 'FakePopen':
         return self
@@ -323,10 +325,44 @@ class TestReturnCodes:
         assert run_backup(out, [str(src)]) == 0
 
         (args,) = fake_popen.calls
-        assert args[0] == '/usr/bin/rsync'
+        assert args[0] == which('rsync')
         assert f'--link-dest={out}/simple_backup/{old_backups[-1]}' in args
         assert args[args.index('/') + 1] == f'{out}/simple_backup/2026-10-14_10-00-00'
 
+    @pytest.mark.parametrize('lines, logged', [
+        ([f'file{n}' for n in range(5)] + ['sent 1 bytes', 'total size is 3'], ['sent 1 bytes', 'total size is 3']),
+        ([], []),
+        (['total size is 3'], ['total size is 3']),
+    ])
+    def test_summary_logged(self, src: Path, out: Path, fake_popen: type[FakePopen], monkeypatch: pytest.MonkeyPatch,
+                            caplog: pytest.LogCaptureFixture, lines: list[str], logged: list[str]) -> None:
+        monkeypatch.setattr(fake_popen, 'output', ''.join(f'{line}\n' for line in lines).encode())
+
+        assert run_backup(out, [str(src)]) == 0
+        assert [m[7:] for m in caplog.messages if m.startswith('rsync: ')] == logged
+
+    @pytest.mark.parametrize('returncode, level', [(0, 'INFO'), (23, 'WARNING'), (1, 'ERROR')])
+    def test_verbose_one_line_per_message(self, src: Path, out: Path, fake_popen: type[FakePopen],
+                                          caplog: pytest.LogCaptureFixture, returncode: int, level: str) -> None:
+        fake_popen.returncode = returncode
+
+        run_backup(out, [str(src)], verbose=True)
+
+        rsync = [(r.levelname, r.getMessage()) for r in caplog.records if r.getMessage().startswith('rsync: ')]
+        lines = ['sending incremental file list', 'sent 1 bytes  received 2 bytes', 'total size is 3']
+        assert rsync == [(level, f'rsync: {line}') for line in lines]
+
+    def test_rsync_missing(self, src: Path, out: Path, tmp_path: Path, fake_popen: type[FakePopen],
+                           old_backups: list[str], monkeypatch: pytest.MonkeyPatch,
+                           caplog: pytest.LogCaptureFixture) -> None:
+        monkeypatch.setenv('PATH', str(tmp_path / 'empty'))
+
+        assert run_backup(out, [str(src)], keep=0, remove_before=True) == 4
+        assert fake_popen.calls == []
+        # Nothing was removed
+        assert backups(out) == old_backups
+        assert 'rsync not found' in caplog.text
+
     @pytest.mark.parametrize('returncode, result, removed', [
         (0, 0, True),
         (24, 0, True),

tests/test_remote.py

@@ -10,7 +10,7 @@ import warnings
 from getpass import GetPassWarning
 from pathlib import Path
 from shutil import which
-from typing import Any, Optional
+from typing import Any
 
 import pytest
 
@@ -30,7 +30,7 @@ class FakeSSH:
         self.home = home
         self.bin_dir = bin_dir
         self.commands: list[str] = []
-        self.fail_on: Optional[str] = None
+        self.fail_on: str | None = None
         self.closed = False
 
     def exec_command(self, command: str) -> tuple[None, io.BytesIO, io.BytesIO]:
@@ -186,7 +186,7 @@ class TestRemoveOldBackups:
         assert [c for c in ssh.commands if 'rm -r' in c][0].startswith('sudo rm -r ')
 
     @pytest.mark.parametrize('names', [[], None])
-    def test_nothing_to_remove(self, remote_home: Path, names: Optional[list[str]]) -> None:
+    def test_nothing_to_remove(self, remote_home: Path, names: list[str] | None) -> None:
         if names is not None:
             make_backups(remote_home, *names)
 
@@ -254,9 +254,11 @@ class RecordPopen:
 
     returncode = 0
     calls: list[list[str]] = []
+    envs: list[dict[str, str] | None] = []
 
     def __init__(self, args: list[str], **kwargs: Any) -> None:
         RecordPopen.calls.append(args)
+        RecordPopen.envs.append(kwargs.get('env'))
         self.stdin = io.BytesIO()
         self.stdout = io.BytesIO(b'sent 1 bytes  received 2 bytes\ntotal size is 3\n')
 
@@ -276,6 +278,7 @@ class TestRsyncArgs:
     def record_popen(self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
         RecordPopen.returncode = 0
         RecordPopen.calls = []
+        RecordPopen.envs = []
         monkeypatch.setattr(sb, 'Popen', RecordPopen)
         # The input must exist locally
         (tmp_path / 'input').mkdir()
@@ -322,19 +325,26 @@ class TestRsyncArgs:
 
     def test_password_auth(self, tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
         monkeypatch.setattr(sb, 'which', lambda cmd: f'/usr/bin/{cmd}')
-        monkeypatch.setenv('SSHPASS', 'secret')
+        monkeypatch.delenv('SSHPASS', raising=False)
         backup = connected_backup()
         backup.inputs = [str(tmp_path / 'input')]
-        backup._password_auth = True
+        backup._password = 'secret'
 
         assert backup.run() == 0
 
         (args,) = RecordPopen.calls
         assert shlex.split(self.ssh_command(args)) == ['sshpass', '-e', 'ssh', '-l', 'user', '-o',
                                                        'StrictHostKeyChecking=accept-new']
-        # The password must not stay in the environment
+        # Only rsync gets the password, never our own environment
+        (env,) = RecordPopen.envs
+        assert env is not None and env['SSHPASS'] == 'secret'
         assert 'SSHPASS' not in os.environ
 
+    def test_no_password_env(self, tmp_path: Path) -> None:
+        self.run(tmp_path)
+
+        assert RecordPopen.envs == [None]
+
     def test_failure(self, tmp_path: Path, remote_home: Path) -> None:
         base = make_backups(remote_home, '2026-10-01_10-00-00')
         RecordPopen.returncode = 23
@@ -348,11 +358,11 @@ class TestRsyncArgs:
 class FakeClient:
     """paramiko.SSHClient stand-in; connect() takes its outcomes from a list"""
 
-    def __init__(self, outcomes: list[Optional[BaseException]]) -> None:
+    def __init__(self, outcomes: list[BaseException | None]) -> None:
         self.outcomes = outcomes
         self.connects: list[dict[str, Any]] = []
         self.policies: list[str] = []
-        self.known_hosts: Optional[str] = None
+        self.known_hosts: str | None = None
         self.closed = False
 
     def load_host_keys(self, filename: str) -> None:
@@ -365,12 +375,12 @@ class FakeClient:
         self.policies.append(type(policy).__name__)
 
     def connect(self, hostname: str, **kwargs: Any) -> None:
-        self.connects.append(kwargs)
+        self.connects.append({'hostname': hostname, **kwargs})
         outcome = self.outcomes.pop(0)
 
         if isinstance(outcome, UserWarning):
             # Like WarningPolicy for an unknown host key
-            warnings.warn(outcome)
+            warnings.warn(outcome, stacklevel=2)
         elif outcome is not None:
             raise outcome
 
@@ -404,8 +414,35 @@ class TestLogin:
         assert remote_backup()._ssh_connect(str(tmp_path)) is client
         assert client.known_hosts == f'{tmp_path}/.ssh/known_hosts'
         assert client.connects[0]['timeout'] == sb.SSH_TIMEOUT
+        assert client.connects[0]['hostname'] == 'server'
+        assert 'port' not in client.connects[0]
         assert not client.closed
 
+    def test_ssh_config(self, client: FakeClient, tmp_path: Path) -> None:
+        (tmp_path / '.ssh').mkdir()
+        key = tmp_path / '.ssh' / 'id_backup'
+        key.touch()
+        (tmp_path / '.ssh' / 'config').write_text(
+            f'Host server\n  HostName backup.example.org\n  Port 2222\n'
+            f'  IdentityFile {key}\n  IdentityFile {tmp_path}/.ssh/missing\n')
+        client.outcomes = [ssh_error(), None]
+
+        assert remote_backup()._ssh_connect(str(tmp_path)) is client
+
+        for params in client.connects:
+            assert (params['hostname'], params['port']) == ('backup.example.org', 2222)
+            assert params['key_filename'] == [str(key)]
+
+    def test_bad_ssh_config(self, client: FakeClient, tmp_path: Path, caplog: pytest.LogCaptureFixture) -> None:
+        (tmp_path / '.ssh').mkdir()
+        (tmp_path / '.ssh' / 'config').write_text('Host server\n  Port abc\n')
+        client.outcomes = [None]
+
+        assert remote_backup()._ssh_connect(str(tmp_path)) is client
+        assert client.connects[0]['hostname'] == 'server'
+        assert 'port' not in client.connects[0]
+        assert 'Cannot read' in caplog.text
+
     @pytest.mark.parametrize('answer, connected', [('y', True), (' Yes', True), ('n', False), ('', False)])
     def test_unknown_host_key(self, client: FakeClient, monkeypatch: pytest.MonkeyPatch,
                               answer: str, connected: bool) -> None:
@@ -444,13 +481,13 @@ class TestLogin:
     def test_password(self, client: FakeClient, monkeypatch: pytest.MonkeyPatch) -> None:
         client.outcomes = [ssh_error(), ssh_error(), None]
         monkeypatch.setattr(sb, 'getpass', lambda prompt: 'secret')
-        monkeypatch.setenv('SSHPASS', '')
+        monkeypatch.delenv('SSHPASS', raising=False)
         backup = remote_backup()
 
         assert backup._ssh_connect() is client
         assert client.connects[-1]['password'] == 'secret'
-        assert backup._password_auth
-        assert os.environ['SSHPASS'] == 'secret'
+        assert backup._password == 'secret'
+        assert 'SSHPASS' not in os.environ
 
     def test_wrong_password(self, client: FakeClient, monkeypatch: pytest.MonkeyPatch) -> None:
         client.outcomes = [ssh_error(), ssh_error(), ssh_error()]
@@ -462,7 +499,7 @@ class TestLogin:
     def test_password_no_terminal(self, client: FakeClient, monkeypatch: pytest.MonkeyPatch,
                                   caplog: pytest.LogCaptureFixture) -> None:
         def no_tty(prompt: str) -> str:
-            warnings.warn('Can not control echo on the terminal.', GetPassWarning)
+            warnings.warn('Can not control echo on the terminal.', GetPassWarning, stacklevel=2)
 
             return ''
 
@@ -474,7 +511,7 @@ class TestLogin:
 
     @pytest.mark.parametrize('outcome, connected', [(None, True), ('error', False)])
     def test_keyfile(self, client: FakeClient, monkeypatch: pytest.MonkeyPatch,
-                     outcome: Optional[str], connected: bool) -> None:
+                     outcome: str | None, connected: bool) -> None:
         pkey = object()
         client.outcomes = [ssh_error(), ssh_error(), ssh_error() if outcome else None]
         monkeypatch.setattr(sb.Backup, '_load_ssh_key', lambda self: pkey)
@@ -548,7 +585,7 @@ class TestLoadKey:
     def test_no_terminal(self, keys: Path, monkeypatch: pytest.MonkeyPatch,
                          caplog: pytest.LogCaptureFixture) -> None:
         def no_tty(prompt: str) -> str:
-            warnings.warn('Can not control echo on the terminal.', GetPassWarning)
+            warnings.warn('Can not control echo on the terminal.', GetPassWarning, stacklevel=2)
 
             return ''
 
@@ -558,7 +595,7 @@ class TestLoadKey:
         assert 'Unable to get passphrase' in caplog.text
 
     @pytest.mark.parametrize('content', [None, 'not a key\n'])
-    def test_bad_file(self, tmp_path: Path, caplog: pytest.LogCaptureFixture, content: Optional[str]) -> None:
+    def test_bad_file(self, tmp_path: Path, caplog: pytest.LogCaptureFixture, content: str | None) -> None:
         keyfile = tmp_path / 'id'
 
         if content is not None:
@@ -566,3 +603,108 @@ class TestLoadKey:
 
         assert remote_backup(ssh_keyfile=str(keyfile))._load_ssh_key() is None
         assert 'Unable to load SSH key' in caplog.text
+
+
+FAKE_SSH = """#!/bin/sh
+# Record the arguments, then run the remote command locally in the fake remote home
+for a in "$@"; do printf '%s\\n' "$a"; done >> "{log}"
+echo --- >> "{log}"
+
+while [ $# -gt 0 ]; do
+    case $1 in
+        -i|-l|-o|-p) shift 2 ;;
+        -*) shift ;;
+        *) break ;;
+    esac
+done
+
+# The host
+shift
+cd "{home}" && HOME="{home}" exec sh -c "$*"
+"""
+
+FAKE_SSHPASS = """#!/bin/sh
+printf '%s' "${{SSHPASS-unset}}" > "{log}"
+# -e
+shift
+exec "$@"
+"""
+
+
+@pytest.mark.usefixtures('connect', 'fake_now')
+class TestRsyncOverSsh:
+    """Whole remote backups: real rsync, with fake ssh and sshpass commands that run the remote side locally"""
+
+    @pytest.fixture(autouse=True)
+    def fake_ssh(self, ssh: FakeSSH, tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+        self.ssh_log = tmp_path / 'ssh.log'
+        self.sshpass_log = tmp_path / 'sshpass.log'
+
+        for name, script, log in [('ssh', FAKE_SSH, self.ssh_log), ('sshpass', FAKE_SSHPASS, self.sshpass_log)]:
+            path = ssh.bin_dir / name
+            path.write_text(script.format(log=log, home=ssh.home))
+            path.chmod(0o755)
+
+        monkeypatch.setenv('PATH', f'{ssh.bin_dir}:{os.environ["PATH"]}')
+        monkeypatch.delenv('SSHPASS', raising=False)
+
+        self.src = tmp_path / 'src dir'
+        self.src.mkdir()
+        (self.src / 'same.txt').write_text('unchanged')
+        (self.src / 'changed.txt').write_text('first')
+
+    def run(self, keep: int = -1, password: str | None = None, **kwargs: Any) -> int:
+        backup = connected_backup(keep=keep, **kwargs)
+        backup.inputs = [str(self.src)]
+        backup._password = password
+
+        return backup.run()
+
+    def ssh_calls(self) -> list[list[str]]:
+        return [c.strip('\n').split('\n') for c in self.ssh_log.read_text().split('---\n') if c != '']
+
+    def copied(self, remote_home: Path, backup: str, name: str) -> Path:
+        return remote_home / 'backups' / 'simple_backup' / backup / str(self.src).lstrip('/') / name
+
+    def test_backups(self, remote_home: Path) -> None:
+        assert self.run() == 0
+        (self.src / 'changed.txt').write_text('second')
+        assert self.run(keep=1) == 0
+        assert self.run(keep=1) == 0
+
+        old, new = '2026-10-14_11-00-00', '2026-10-14_12-00-00'
+        assert remote_dirs(remote_home / 'backups' / 'simple_backup') == [old, new]
+        assert self.copied(remote_home, new, 'changed.txt').read_text() == 'second'
+        # Unchanged files are hard-linked to the previous backup (--link-dest on the server)
+        assert self.copied(remote_home, old, 'same.txt').stat().st_ino == \
+            self.copied(remote_home, new, 'same.txt').stat().st_ino
+
+        for call in self.ssh_calls():
+            assert call[:5] == ['-o', 'StrictHostKeyChecking=accept-new', '-l', 'user', 'server']
+            # rsync passes the remote command as separate arguments
+            assert call[5:7] == ['rsync', '--server']
+
+    def test_keyfile(self, remote_home: Path) -> None:
+        assert self.run(ssh_keyfile='/keys/my key') == 0
+
+        (call,) = self.ssh_calls()
+        assert call[:4] == ['-i', '/keys/my key', '-o', 'StrictHostKeyChecking=accept-new']
+
+    def test_password(self, remote_home: Path) -> None:
+        assert self.run(password='secret') == 0
+
+        assert self.sshpass_log.read_text() == 'secret'
+        assert 'SSHPASS' not in os.environ
+        assert len(remote_dirs(remote_home / 'backups' / 'simple_backup')) == 1
+
+    def test_remote_sudo(self, remote_home: Path) -> None:
+        assert self.run() == 0
+        assert self.run(keep=0, remote_sudo=True) == 0
+
+        assert remote_dirs(remote_home / 'backups' / 'simple_backup') == ['2026-10-14_11-00-00']
+        assert self.ssh_calls()[-1][5:7] == ['sudo rsync', '--server']
+
+    def test_progress(self, remote_home: Path, capsys: pytest.CaptureFixture[str]) -> None:
+        assert self.run(progress=True) == 0
+
+        assert '100%' in capsys.readouterr().err

tests/test_state.py

@@ -0,0 +1,137 @@
+"""Tests for the last backup state file and --last-backup"""
+
+import os
+import pwd
+from collections.abc import Callable
+from datetime import datetime, timedelta
+from pathlib import Path
+
+import pytest
+
+from simple_backup import simple_backup as sb
+
+DESTINATION = '/backups/simple_backup/2026-10-25_10-00-00'
+
+
+@pytest.fixture(autouse=True)
+def as_user(monkeypatch: pytest.MonkeyPatch) -> None:
+    """Run as a non-root user (the tests may run as root in a chroot)"""
+
+    monkeypatch.setattr(os, 'geteuid', lambda: 1000)
+    monkeypatch.setenv('USER', 'user')
+
+
+@pytest.fixture
+def state(tmp_path: Path) -> Path:
+    return tmp_path / 'state' / 'simple_backup' / 'last_backup'
+
+
+def write_state(state: Path, text: str) -> None:
+    state.parent.mkdir(parents=True)
+    state.write_text(text)
+
+
+def test_write(state: Path) -> None:
+    sb._write_state(None, DESTINATION)
+
+    time, destination = state.read_text().splitlines()
+    assert abs(datetime.now().astimezone() - datetime.fromisoformat(time)) < timedelta(minutes=1)
+    assert destination == DESTINATION
+    # No temporary file left behind
+    assert os.listdir(state.parent) == ['last_backup']
+
+
+def test_overwrite(state: Path) -> None:
+    write_state(state, '2026-10-01T10:00:00+02:00\n/old\n')
+
+    sb._write_state(None, DESTINATION)
+
+    assert state.read_text().splitlines()[1] == DESTINATION
+
+
+def test_relative_xdg_state_home_ignored(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+    monkeypatch.setenv('XDG_STATE_HOME', 'relative')
+    monkeypatch.setenv('HOME', str(tmp_path / 'home'))
+
+    sb._write_state(None, DESTINATION)
+
+    assert (tmp_path / 'home' / '.local' / 'state' / 'simple_backup' / 'last_backup').exists()
+
+
+def test_write_error(monkeypatch: pytest.MonkeyPatch, tmp_path: Path, caplog: pytest.LogCaptureFixture) -> None:
+    # A file where the state directory should be
+    (tmp_path / 'not a dir').write_text('')
+    monkeypatch.setenv('XDG_STATE_HOME', str(tmp_path / 'not a dir'))
+
+    sb._write_state(None, DESTINATION)
+
+    assert 'Cannot save the time of the last backup' in caplog.text
+
+
+def test_root_writes_as_user(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+    calls: list[tuple[str, int]] = []
+    egid = os.getegid()
+    owner = pwd.struct_passwd(('user', 'x', 1000, 1001, '', str(tmp_path / 'home'), '/bin/sh'))
+
+    monkeypatch.setattr(os, 'geteuid', lambda: 0)
+    monkeypatch.setattr(pwd, 'getpwnam', lambda name: owner)
+    monkeypatch.setattr(os, 'seteuid', lambda uid: calls.append(('euid', uid)))
+    monkeypatch.setattr(os, 'setegid', lambda gid: calls.append(('egid', gid)))
+
+    sb._write_state('user', DESTINATION)
+
+    # Root's XDG_STATE_HOME is not used
+    assert (tmp_path / 'home' / '.local' / 'state' / 'simple_backup' / 'last_backup').exists()
+    assert calls == [('egid', 1001), ('euid', 1000), ('euid', 0), ('egid', egid)]
+
+
+class TestStateOwner:
+    def test_non_root(self) -> None:
+        assert sb._state_owner('user') is None
+
+    @pytest.mark.parametrize('name, expected', [('user', 'user'), ('root', None), ('unknown', None), (None, None)])
+    def test_root(self, monkeypatch: pytest.MonkeyPatch, name: str | None, expected: str | None) -> None:
+        users = {'user': pwd.struct_passwd(('user', 'x', 1000, 1000, '', '/home/user', '/bin/sh')),
+                 'root': pwd.struct_passwd(('root', 'x', 0, 0, '', '/root', '/bin/sh'))}
+
+        def getpwnam(name: str) -> pwd.struct_passwd:
+            if name not in users:
+                raise KeyError(name)
+
+            return users[name]
+
+        monkeypatch.setattr(os, 'geteuid', lambda: 0)
+        monkeypatch.setattr(pwd, 'getpwnam', getpwnam)
+
+        owner = sb._state_owner(name)
+        assert (owner.pw_name if owner is not None else None) == expected
+
+
+class TestShow:
+    @pytest.mark.parametrize('days, age', [(0, 'today'), (1, 'yesterday'), (3, '3 days ago')])
+    def test_age(self, run_cli: Callable[..., int], state: Path, capsys: pytest.CaptureFixture[str],
+                 days: int, age: str) -> None:
+        completed = (datetime.now() - timedelta(days=days)).replace(hour=12, minute=30).astimezone()
+        write_state(state, f'{completed.isoformat(timespec="seconds")}\n{DESTINATION}\n')
+
+        assert run_cli('--last-backup') == 0
+        assert capsys.readouterr().out == \
+            f'Last backup: {completed:%Y-%m-%d} 12:30 ({age})\nDirectory: {DESTINATION}\n'
+
+    def test_after_write(self, run_cli: Callable[..., int], capsys: pytest.CaptureFixture[str]) -> None:
+        sb._write_state(None, DESTINATION)
+
+        assert run_cli('--last-backup') == 0
+        assert '(today)' in capsys.readouterr().out
+
+    def test_no_backup(self, run_cli: Callable[..., int], capsys: pytest.CaptureFixture[str]) -> None:
+        assert run_cli('--last-backup') == 1
+        assert capsys.readouterr().out == 'No backup recorded yet\n'
+
+    @pytest.mark.parametrize('text', ['', '2026-10-25T10:00:00+02:00\n', 'yesterday\n/backups\n'])
+    def test_bad_file(self, run_cli: Callable[..., int], state: Path, capsys: pytest.CaptureFixture[str],
+                      text: str) -> None:
+        write_state(state, text)
+
+        assert run_cli('--last-backup') == 1
+        assert 'Cannot read' in capsys.readouterr().err