review

nixos/doc/manual/release-notes/rl-2405.section.md

@@ -286,6 +286,10 @@ The pre-existing [services.ankisyncd](#opt-services.ankisyncd.enable) has been m
   [fileSystems.overlay](#opt-fileSystems._name_.overlay.lowerdir). See also the
   [NixOS docs](#sec-overlayfs).
 
+- systemd units can now specify the `Upholds=` and `UpheldBy=` unit dependencies via the aptly
+  named `upholds` and `upheldBy` options. These options get systemd to enforce that the
+  dependencies remain continuosly running for as long as the dependent unit is in a running state.
+
 - `stdenv`: The `--replace` flag in `substitute`, `substituteInPlace`, `substituteAll`, `substituteAllStream`, and `substituteStream` is now deprecated if favor of the new `--replace-fail`, `--replace-warn` and `--replace-quiet`. The deprecated `--replace` equates to `--replace-warn`.
 
 - A new hardening flag, `zerocallusedregs` was made available, corresponding to the gcc/clang option `-fzero-call-used-regs=used-gpr`.

nixos/lib/systemd-unit-options.nix

@@ -160,13 +160,7 @@ in rec {
         default = [];
         type = types.listOf unitNameType;
         description = lib.mdDoc ''
-          Configures dependencies similar to Wants=, but as long as this unit is up, all units
-          listed in Upholds= are started whenever found to be inactive or failed, and no job is
-          queued for them. While a Wants= dependency on another unit has a one-time effect when
-          this units started, a Upholds= dependency on it has a continuous effect, constantly
-          restarting the unit if necessary. This is an alternative to the Restart= setting of
-          service units, to ensure they are kept running whatever happens. The restart happens
-          without delay, and usual per-unit rate-limit applies.
+          Keeps the specified running while this unit is running. A continuous version of `wants`.
         '';
       };