[RFC 0124] Do not auto-close stale Nix issues and PRs, matching Nixpkgs's policy (#124)

* nix-mark-stale-issues: Copy template

* nix-mark-stale-issues: First draft

* stale-nix-no-close: Update

* stale-nix-no-close: Make the diff less normative

* nix-mark-stale-issues: Fix typo

Thanks!

Co-authored-by: Niklas Hambüchen <mail@nh2.me>

Co-authored-by: Niklas Hambüchen <mail@nh2.me>

rfcs/0000-nix-mark-stale-issues.md

@@ -0,0 +1,112 @@
+---
+feature: nix-mark-stale-issues
+start-date: 2022-04-18
+author: John Ericson (@Ericson2314)
+co-authors: (find a buddy later to help out with the RFC)
+shepherd-team: @ryantm, @nh2, @infinisil
+shepherd-leader: @ryantm
+related-issues: (will contain links to implementation PRs)
+---
+
+# Summary
+[summary]: #summary
+
+Do not auto-close Nix issues and PRs.
+
+Make the policy clear, and harmonize Nix's with Nixpkgs's, which was approved by
+[RFC 51](https://github.com/NixOS/rfcs/blob/master/rfcs/0051-mark-stale-issues.md).
+
+# Motivation
+[motivation]: #motivation
+
+## Background
+
+In 2019, after much discussion,
+[RFC 51](https://github.com/NixOS/rfcs/blob/master/rfcs/0051-mark-stale-issues.md) was approved to mark old Nixpkgs issues and PRs as stale,
+but not close anything.
+
+In 2021, @garbas contributed [Nix PR 4526](https://github.com/NixOS/nix/pull/4526),
+which initially just made a stale bot configuration in line with Nixpkgs.
+But @edolstra [specifically requested](https://github.com/NixOS/nix/pull/4526#discussion_r571687438) that stale items do be closed.
+To be clear, there *is* no formal violation, as that RFC was just about Nixpkgs, but we should reconsider whether this was a good idea.
+
+## Clear policy
+
+Firstly, whatever the policy is, it should be clearly announced.
+
+Without a big announcement of this decision, many of us were caught off guard when issues were closed the other day.
+Anyone that just saw the previous stale bot "marking stale" messages probably assumed stale bot was configured like Nixpkgs.
+Without knowing that auto-closing was enabled, people who might have bothered to aggressively triage stale issues before the auto-close deadline didn't.
+For the social aspects of the stale bot auto-closing to work as intended, it is very important people *do* know the policy, because incentivizing that triaging by the threat of auto-closing is precisely the point!
+
+This RFC, no matter the outcome, can help make the policy clear and known to all.
+
+## Consistent policy
+
+All things equal, it is probably not a good idea to pick a different policy for Nix than the one decided by the community for Nixpkgs.
+The strong opinions in RFC 51 attest do attest that the community doesn't like auto-closing in that context.
+Many of those strong opinions apply to issue tracking for open source project in general, not just for Nixpkgs in particular.
+
+## Nix's particular backlog
+
+Still, we might ask whether the situation in Nix is different from Nixpkgs in ways that would motivate a different decision.
+We would in fact argue the opposite: that Nix is an especially *poor* candidate for auto-closing.
+Nix's backlog in particular reflects a long history of the community being able to raise issues without being empowered to address their own issues.
+This asymmetry inevitably led an ever-growing backlog.
+
+We are doing somewhat better now, but have been busy just trying to keep up with new issues, and not yet working retroactively through the backlog as a team.
+To finish turning a new leaf, it would be very healthy gesture to go through that backlog, atoning for the prior state of affairs.
+Closing the backlog without review forfeits that opportunity.
+
+## Summary
+
+For these reasons, we advocate in priority order:
+
+1. Making the policy, whatever it may be, loud and clear.
+
+2. Making the Nix policy match the Nixpkgs policy, for simplicity.
+
+3. Making the Nix policy not auto-close, in light of the special situation of how the backlog arose in the first place.
+
+# Detailed design
+[design]: #detailed-design
+
+1. Follow the stale policy of nixpkgs, except Nix may have different exempt labels.
+
+   That should look something like this diff to the `.github/stale.yml` configuration file:
+   ```diff
+   diff --git a/.github/stale.yml b/.github/stale.yml
+   index fe24942f4..539720b6d 100644
+   --- a/.github/stale.yml
+   +++ b/.github/stale.yml
+   @@ -1,10 +1,8 @@
+    # Configuration for probot-stale - https://github.com/probot/stale
+    daysUntilStale: 180
+   -daysUntilClose: 365
+   +daysUntilClose: false
+    exemptLabels:
+      - "critical"
+   +  - "never-stale"
+    staleLabel: "stale"
+   -markComment: |
+   -  I marked this as stale due to inactivity. → [More info](https://github.com/NixOS/nix/blob/master/.github/STALE-BOT.md)
+   -closeComment: |
+   -  I closed this issue due to inactivity. → [More info](https://github.com/NixOS/nix/blob/master/.github/STALE-BOT.md)
+   +markComment: false
+   +closeComment: false
+   ```
+
+2. Reopen recently auto-closed items, either automatically *en masse*, or manually allowing some triage.
+   The route will be chosen based on human resourcing constraints; it is unclear which is less work.
+
+# Drawbacks
+[drawbacks]: #drawbacks
+
+Manually combing through the backlog takes time.
+
+# Alternatives
+[alternatives]: #alternatives
+
+1. Align Nixpkgs's and Nix's configs some other way.
+
+2. Leave config as-is.