Troubleshooting

Rewyyn uses a client-server architecture. A background server owns sessions, plugins, permissions, and other application state. Start by determining whether an issue is in a client, the shared server, or a specific project.

Check the background service

Show the current server information:

rewyyn service status

Verify that its API is healthy:

rewyyn api get /api/info

If the service is stuck or unhealthy, restart it:

rewyyn service restart

You can also stop and start it explicitly:

rewyyn service stop
rewyyn service start

Allow a browser origin

If a browser client on another origin cannot connect because of CORS, add the client’s origin to the service configuration:

rewyyn service set cors http://192.168.1.10:3001
rewyyn service get cors

Use an exact HTTP or HTTPS origin, including the port when needed, without a path or trailing slash. To allow multiple origins, pass a comma-separated list as one argument; whitespace around each origin is trimmed:

rewyyn service set cors "http://192.168.1.10:3001, https://app.example.com"

service get cors prints a JSON array. Remove the configured list with:

rewyyn service unset cors

Setting or unsetting service configuration stops the background service. Its next start picks up the new configuration; use rewyyn service start to start it explicitly.

For a foreground server, repeat --cors for each additional allowed origin:

rewyyn serve --cors http://192.168.1.10:3001 --cors https://app.example.com

With serve --service, supplied --cors flags override the persisted list for that process. Without those flags, service mode uses the persisted list. CORS does not change the listening address or bypass server authentication.

Inspect the API

The api command uses the local service discovery and authentication flow. It accepts either an HTTP method and path or an OpenAPI operation ID.

See the API reference for all endpoints and operation IDs.

Pass a JSON request body with --data or -d, and add headers with --header or -H.

Read logs

Installed builds write logs to:

~/.local/share/rewyyn/log/rewyyn.log

Follow the log while reproducing the problem:

tail -f ~/.local/share/rewyyn/log/rewyyn.log

Each line includes a process run ID and a role field. Use role=server for session, provider, plugin, permission, and tool activity.

grep 'role=server' ~/.local/share/rewyyn/log/rewyyn.log
grep 'run=8fc3b1d5' ~/.local/share/rewyyn/log/rewyyn.log

Capture a heap snapshot

Write a memory (heap) snapshot of the running background server on any platform:

rewyyn debug heap-dump

The command waits until the snapshot is complete, then prints its path:

/home/me/.local/share/rewyyn/log/heap-48213-2026-10-23T013012345Z.heapsnapshot

Write it somewhere else with --directory. The server creates the directory when it is missing:

rewyyn debug heap-dump --directory ./snapshots

• It only uses a server that is already running. It never starts, replaces, or restarts one.
• Use --server <url> to capture a server you started with rewyyn serve. Set REWYYN_PASSWORD if it has one. --directory is then a path on the server’s machine.
• Open the file in the Memory panel of Chrome DevTools.

In the desktop app

Run Capture heap snapshots from the command palette. It writes one folder in your Downloads folder with a snapshot of each part of the app, plus a breakdown of the memory a snapshot cannot show:

rewyyn-heap-2026-10-23T013012345Z/
  memory.json                  where the memory is, per process, in MiB: start here
  memory-infra.json            Chromium's memory dump trace; open it in https://ui.perfetto.dev
  heap-48213-….heapsnapshot    the desktop's own server
  window-1-48390.heapsnapshot  one per app window
  main-48102.heapsnapshot      the desktop main process
  gpu.json                     the GPU and driver
  manifest.json                processes, PIDs, and memory before and after; written last

• A heap snapshot holds only JavaScript objects and the page. Images, layout, compositor layers and GPU memory are in memory.json and memory-infra.json instead.
• Remote servers are not captured. Use rewyyn debug heap-dump on that machine instead.
• The server writes its snapshot straight into the folder, so nothing large is moved or copied.
• Browser tabs are not included, because their snapshots contain the content of the pages you visited.

Capture CPU and memory profiles

On macOS and Linux, you can signal a running Rewyyn process to capture diagnostic data. Get the background server PID from the health endpoint:

rewyyn api get /api/info

Use the pid from the response with one of these signals:

• SIGPROF captures a ten-second CPU profile:

  kill -SIGPROF <pid>

  The result is written to the log directory as cpu-<pid>-<timestamp>.cpuprofile.

• SIGUSR1 captures a memory (heap) snapshot:

  kill -SIGUSR1 <pid>

  The result is written to the log directory as heap-<pid>-<timestamp>.heapsnapshot.

Wait for CPU profile written or heap snapshot written in rewyyn.log before opening the file. The corresponding log entry includes its complete path. You can inspect both file types in Chrome DevTools.

Service files

The shared server registers itself at:

~/.local/state/rewyyn/service.json

Its private service configuration is stored separately at:

~/.config/rewyyn/service.json

The database normally lives at:

~/.local/share/rewyyn/rewyyn.db

REWYYN_DB can override the database location.

Report an issue

Include the following when reporting a reproducible problem:

• Output from rewyyn --version
• Output from rewyyn service status
• The smallest sequence of steps that reproduces the issue
• Whether the issue affects the shared service, a specific client, or one project
• Relevant log lines, including their run and role fields

Remove API keys, authorization headers, prompts, file contents, and other sensitive data before sharing logs.

File reproducible problems in desktop feedback.