diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..1d953f4
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use nix
diff --git a/mpbackup b/mpbackup
index 594526b..0613d7d 100644
--- a/mpbackup
+++ b/mpbackup
@@ -6,7 +6,7 @@ require 'yaml'
 
 DEFAULT_CONFIG_FILE = Pathname.new('/etc/mpbackup/config.yaml')
 NAME = 'mpbackup'
-VERSION = '0.6.0'
+VERSION = '0.4.0'
 
 def set_restic_vars(config)
   if config['repository-file']
@@ -23,10 +23,6 @@ def set_restic_vars(config)
   else
     password = STDIN.getpass('Please put in your restic password: ')
   end
-  if config['cache-dir']
-    puts "Setting RESTIC_CACHE_DIR to #{config['cache-dir']} …"
-    ENV['RESTIC_CACHE_DIR'] = config['cache-dir']
-  end
 
   ENV['RESTIC_REPOSITORY'] = repo
   ENV['RESTIC_PASSWORD'] = password
@@ -35,13 +31,6 @@ end
 def unset_restic_vars
   ENV.delete('RESTIC_REPOSITORY')
   ENV.delete('RESTIC_PASSWORD')
-  ENV.delete('RESTIC_CACHE_DIR')
-end
-
-def set_restic_path(config)
-  if !config.key? 'restic-path'
-    config['restic-path'] = 'restic'
-  end
 end
 
 def error(exit_status, message)
@@ -49,39 +38,35 @@ def error(exit_status, message)
   exit exit_status
 end
 
-def check(config)
+def check
   puts 'Checking restic repo …'
-  check_command = [config['restic-path'], 'check']
+  check_command = ['restic', 'check']
   puts("Command: #{check_command.join(' ')}")
   system(*check_command)
   if $?.exitstatus > 0
-    error(1, "Checking restic repository failed.")
+    error(1, "Checking restic repository #{ENV['RESTIC_REPOSITORY']} failed.")
   end
 end
 
 def backup(config)
   puts "Backing up with restic …"
   # https://restic.readthedocs.io/en/latest/040_backup.html#including-and-excluding-files
-  flags = config['backup'].select{|k,v|
-    k != 'exclude' && k != 'paths' && k != 'tags'}
-  flags = flags.map{|k,v| "--#{k}=#{v.to_s}"}
   exclude = config.dig('backup', 'exclude')&.flat_map{|e| ['--exclude', e]} || []
-  tags = config.dig('backup', 'tags')&.flat_map{|t| ['--tag', t]} || []
   paths = config.dig('backup', 'paths') || []
-  backup_command = [config['restic-path'], 'backup', *exclude, *paths, *flags]
+  backup_command = ['restic', 'backup', *exclude, *paths]
   puts("Command: #{backup_command.join(' ')}")
   system(*backup_command)
   if $?.exitstatus > 0
     error(1, 'Failed to do backup.')
   end
 
-  check(config)
+  check
 
   if config.dig('forget', 'enable')
     puts 'Forgetting unnecessary snapshots …'
     flags = config['forget'].select{|k,v| k != 'enable'}
     flags = flags.flat_map{|k,v| ['--' + k, v.to_s]}
-    forget_command = [config['restic-path'], 'forget'] + flags
+    forget_command = ['restic', 'forget'] + flags
     puts("Command: #{forget_command.join(' ')}")
     system(*forget_command)
     # Data will only be deleted when `restic prune` is executed or when
@@ -94,7 +79,7 @@ end
 
 def prune(config)
   puts 'Pruning restic repo …'
-  prune_command = [config['restic-path'], 'prune']
+  prune_command = ['restic', 'prune']
   puts("Command: #{prune_command.join(' ')}")
   system(*prune_command)
   if $?.exitstatus > 0
@@ -107,13 +92,12 @@ end
 def run_restic(config)
   puts 'Executing restic with the following arguments …'
   puts "ARGV: #{ARGV}"
-  exec(config['restic-path'], *ARGV)
+  exec('restic', *ARGV)
 end
 
 def act(config, options)
   puts "Applying configuration ‘#{config['name']}’ …"
   set_restic_vars(config)
-  set_restic_path(config)
   if options[:prune]
     prune config
   elsif options[:run_restic]