Add guidance for using Linear during trial (#8649)

Author: varungandhi-src

content/departments/engineering/linear-trial.md

@@ -0,0 +1,237 @@
+# Using Linear at Sourcegraph (trial)
+
+<!--
+TODOs post adoption:
+- Remove trial from doc title
+- Combine with 'working with issues' doc
+- Update guidance around label groups.
+- Update mentions of Eng Private team if we
+  merge that with main Eng team. Maybe we still need
+  a separate OSS team for OSS repos.
+-->
+
+This document describes recommended ways of using Linear
+during the trial period, without causing a disruption to
+team members who continue using GitHub
+and are not part of the trial.
+
+While the [Linear docs](https://linear.app/docs) are excellent,
+here is a very quick run down of the core mental model.
+
+- The workspace is divided into Teams.
+  - Settings related to workflow (issue statuses, estimates, cycles),
+    templates (for issues, projects etc.), syncing with external tools
+    and so on are customizable per Team.
+- **Issues** are the smallest unit of work.
+  - Issues can have sub-issues, be blocked by other issues etc.
+  - An Issue belongs to a single Team: the issue identifier includes
+    a short prefix based on the Team. (Example: ENG-123)
+- **Views** allow slicing/dicing Issues in flexible ways.
+  - Views work both within Teams and across Teams.
+- **Projects** allow grouping issues into more coherent units.
+  - A Project belongs to a single Team, but can contain issues
+    that belong to other Teams.
+  - Project can have Documents that allow inline comment threads
+    similar to Google Docs.
+- **Roadmaps** allow grouping projects into larger units,
+  and are owned at the workspace level.
+
+For more details, see the [conceptual model docs](https://linear.app/docs/conceptual-model).
+
+## Logging in
+
+Install the [Linear app](https://linear.app/download) or
+go to [our Linear workspace](https://linear.app/sourcegraph)
+and log in with SAML SSO.
+
+## Team structure
+
+For now, we will aim to use coarse-grained teams.
+To start out with, there are 5 teams: Eng PUBLIC,
+Eng Private, Product, Design and Implementation.
+
+Teammates in other parts of the company interested
+in testing out Linear should feel free to create new Teams.
+
+### Eng PUBLIC and Eng Private
+
+Eng PUBLIC has _full_ bidirectional syncing with `sourcegraph/sourcegraph`.
+This means that the following will be synced across,
+regardless of whether the change is made in Linear or GitHub:
+
+1. New issues being created.
+2. Changes to labels, issue title, issue description,
+   new comments (for the "GitHub thread" in Linear), and
+   open/close status.
+
+All other repositories have _partial_ bidirectional syncing,
+which means that out of (1) and (2) above, only (2) is enabled,
+i.e. new issues created in Linear will not be synced to GitHub.
+This applies to:
+
+- `sourcegraph/customer` - synced with Eng Private
+- `sourcegraph/cody`
+- `sourcegraph/src-cli`
+- `sourcegraph/scip`, `sourcegraph/scip-java` and other indexers
+- All other private repositories that have syncing turned on.
+  The full list of repos with syncing can be found [here](https://linear.app/sourcegraph/settings/integrations/github).
+
+Both Eng PUBLIC and Eng Private are configured to use [2 week cycles](https://linear.app/docs/use-cycles)
+based on [RFC 916](https://docs.google.com/document/d/16mipKz0fc2Ki5NYXG8Rarb8b4KHh34t27P9Ao_m8e-o/edit).
+
+## Adding a new repository (for Engineering)
+
+You can ask for help in `#wg-linear-trial` with these steps as well.
+
+1. Add the repository to the [GitHub integration](https://linear.app/sourcegraph/settings/integrations/github).
+   If you do not see repositories in the Sourcegraph GitHub org listed here,
+   you may need to request the `sourcegraph - Owner` GitHub permission in Entitle.
+
+   - For private repos, use the `Eng Private` team.
+   - For public repos, use the `Eng PUBLIC` team.
+
+   DO NOT enable the "Enable bidirectional sync" toggle;
+   it only applies to _new issues_ created in Linear.
+   Comments, label changes, title and description changes will
+   still sync bidirectionally even if that toggle is disabled.
+   See the [FAQ](#faq) for more details.
+
+2. Under [Import / Export](https://linear.app/sourcegraph/settings/import-export),
+   add a GitHub repository. After clicking 'Connect to GitHub' there may
+   be a delay of 10-15s before you see the options for selecting a repo.
+
+   If you do not see repositories in the Sourcegraph GitHub org listed here,
+   you may need to request the `sourcegraph - Owner` GitHub permission in Entitle.
+
+   - If present, disable the toggle for importing data from organization level projects.
+   - Enable the toggle for importing data from closed issues.
+   - Select the team to import issues into:
+     - For private repos, use the `Eng Private` team.
+     - For public repos, use the `Eng PUBLIC` team.
+
+   After importing is complete, you will have the option to configure it.
+   Make sure all these checkboxes are checked:
+
+   - Import N open issues
+   - Import N stale issues to Archive
+   - Import N closed or done issues to Archive
+   - Sync issues after import
+
+   So that syncing is maintained for old issues, and all issue history
+   is available for search.
+
+   After this step, select 'Import users' and make sure that:
+
+   - If a person has 'Map to Existing' but no associated account on
+     the right side, then change it to 'Do not create'
+   - Replace any 'Create with email' with 'Do not create'
+
+   Once you click next, confirm on the next page that:
+
+   - The number of user invites is zero
+   - The number of completed issues matches up with the closed
+     issues in the repo's GitHub issue tracker.
+
+At the moment, all repos except for the monorepo use an extra issue label
+to allow filtering for views inside Linear. For example, the `scip-java`
+repo uses the `graph/scip-java` label.
+Here is an [example PR](https://github.com/sourcegraph/scip-java/pull/685/files)
+for auto-adding the label to new issues.
+For old issues, you can quickly add the label after importing into Linear.
+
+## Dos and Don'ts
+
+1.  **Don't create new Teams for sub-teams in Engineering**
+    (except for testing Linear features, that's OK).
+    Instead, let's try to tweak existing settings or enable new ones
+    which would be useful to all teams.
+2.  **Do add other repositories of interest to Linear**.
+    - Even for repos which only have PRs, if the PR descriptions
+      use Linear identifiers such as `Fixes ENG-123`,
+      then the corresponding issue will be auto-closed.
+    - Caveat: Do not enable bidirectional syncing for other repos
+      in Eng PUBLIC or Eng Private.
+3.  If your team is on-board, **do connect your team's #discuss
+    channel with Eng Private using Linear Asks**
+    ([here](https://linear.app/sourcegraph/settings/asks))
+    to easily turn Slack threads into issues. ([docs](https://linear.app/docs/linear-asks))
+4.  **Avoid creating new label groups inside Linear**
+    (creating new labels, is OK). - If you attempt to create a new label with `/` on-the-fly
+    when editing an issue, Linear will create a label group
+    instead of a "flat" label.
+
+    For example, if you type `X/Y` for a new label, it will create
+    a group `X` with a label `Y` in that group. Since `X` is the
+    group name, the label synced to GitHub will be just `Y`.
+    This may be confusing to someone seeing the issue on GitHub
+    as the prefix is no longer available.
+
+    - Label groups also have at-most-one semantics - you can't apply
+      multiple labels from the same group to a single issue.
+    - Alternative: you can create a label with `/` from the Team's settings
+      ([example link](https://linear.app/sourcegraph/settings/teams/ENG/labels)).
+
+5.  **Do explore the various Linear [features](https://linear.app/docs)
+    and [integrations](https://linear.app/sourcegraph/settings/integrations)**.
+
+## FAQ
+
+### Why are Eng PUBLIC and Eng Private separate?
+
+The Eng Private team is present because of the following
+considerations:
+
+1. We have some private repositories on GitHub.
+2. We'd like to use bidirectional syncing for the trial
+   period to avoid disrupting people not using Linear.
+3. To test out whether Linear can work well as a single
+   pane of glass for issues, we need to sync issues from
+   our private repos into Linear.
+4. The Linear -> GitHub sync direction uses the default
+   repo set in the GitHub integration, instead of offering
+   a repo picker.
+5. The default repo for Eng PUBLIC is sourcegraph/sourcegraph
+   for ease of use.
+
+The above factors create the risk of an information leak
+if someone creates an issue in Linear with customer details.
+
+Eng Private also provides a natural place to create issues
+from Slack threads which may have customer details.
+
+### Why not create separate Linear Teams for each sub-team in Engineering?
+
+We initially considered doing this but decided against it
+for the following reasons:
+
+- It would create a proliferation of issue prefixes in identifiers,
+  making it harder to identify the top-level team based on the identifier.
+- If there were any re-orgs in the future, having the issue identifiers
+  change to reflect new team names would be a disorienting experience,
+  especially for teammates outside Engineering.
+- For teammates outside Engineering, it would be valuable to reduce
+  the number of potential places to file issues.
+
+However, if the flexibility provided by the current team structure
+is not enough, then we can consider creating smaller Teams in Linear
+at the end of the trial (around mid May).
+
+### Why don't we have full bidirectional syncing for all repos?
+
+This limitation is present because Linear doesn't offer a repo picker
+in the UI if bidirectional issue creation syncing is
+enabled for more than 1 repo.
+
+This means that even if we enabled
+bidirectional syncing for say `sourcegraph/cody` with the Eng PUBLIC
+Team, you couldn't actually create issues which sync to that repo directly
+in the UI. To have that work, we'd have to create a separate Cody Team
+in Linear with `sourcegraph/cody` being it's default bidirectional syncing repo.
+
+However, that would defeat the above goal of avoiding creating
+separate Linear Teams for each sub-team in Engineering.
+
+## Known restrictions
+
+- No custom fields for Issues.
+- An issue can have at most one assignee (DRI model).