Source: https://reporules.fyi/shiny/

# Shiny: Perch rule pack

2 saved requirements for Shiny. Inspect the selectors and adapt the example paths to your repository.

```
- name: write-observer-checks-permission
  where: "R/order_module.R"
  ensure: >-
    The cancellation observeEvent must require identity$can_cancel before invoking updateOrder, not just a non-null identity.

- name: session-removes-report-workspace
  where: "R/report_workspace.R"
  ensure: >-
    The onSessionEnded callback must unlink the session-created workspace recursively instead of leaving report files behind.
```

[Download the rule pack ZIP](https://reporules.fyi/shiny/rule-pack.zip) · [Download YAML](https://reporules.fyi/shiny/rules.yaml) · [Agent repair task](https://reporules.fyi/shiny/agent-task.txt) · [Implementation, integration requirements and captured checks](https://frameworkrecipes.dev/shiny/)

## Install the rule without replacing your configuration

```
npm install -g @lakeday/perch
perch login
curl -fL 'https://reporules.fyi/shiny/rule-pack.zip' -o 'perch-guide-shiny.zip'
unzip -n 'perch-guide-shiny.zip'
```

Keep your existing perch.yaml. Extraction preserves existing files and adds .perch/rules/perch-guide-shiny.yaml. Review each where selector before running a check on your application.

## Configure your coding agent

```
perch setup claude-code
perch setup codex
perch setup cursor
perch setup pi
```

Choose the setup command for the agent you use.

## Check the edit, fix the finding, check again

```
perch check R/order_module.R --rules write-observer-checks-permission --json
perch check R/report_workspace.R --rules session-removes-report-workspace --json
```

Run the check after an agent edit. Read the finding and affected code, repair the implementation, and repeat the identical command. Keep the application regression tests as separate gates.

Exit 3 means a finding. Exit 1 or 2 means the check did not complete. A pass does not prove application correctness. Fresh judgments can vary; unchanged requests reuse cached answers. Relevant source is sent to the configured model service.

[Pack manifest and SHA-256 hash](https://reporules.fyi/shiny/rule-pack.json) · [Pack README](https://reporules.fyi/shiny/rule-pack-readme.md)

**Repo Rules**

Requirements that stay in the repo.

Published by Perch · © 2026 Verglas LLC. Repo Rules is a Perch publication.

Perch’s MIT license covers the CLI; hosted model analysis is a paid service. Relevant source is sent to the configured model service.

[Perch CLI MIT license](https://github.com/lakeday-org/perch/blob/main/LICENSE) · [Article text](https://reporules.fyi/shiny/index.md) · [Resource index](https://reporules.fyi/llms.txt)