project-stratum

Almost done — exporting the image now. Let me wait for it to finish.

Still exporting layers. This is the slow part — writing the ~2GB+ image. Let me wait longer.

Still exporting. Let me wait another 2 minutes.

Image exported, now unpacking. Almost there.

Still unpacking. Let me wait more.

Looking great — health checks passing! Almost deployed.

Deployed! Let me check the final output.

Deployed successfully. Let me verify it's working.

Deploy is live and returning 200. The shared param panel with localStorage persistence is now deployed at https://stratum.sandscape.cc/showcase?method=stem_waveform.

shows black image for stem waveforms

Let me check the showcase page and the canvas component.

Let me check what the stem data API actually returns for one of the tracks.

Data looks fine — non-zero values. Let me check if this is a canvas binding timing issue. The problem is likely that when stemData loads and the canvas appears in DOM, the rendering $effect doesn't re-trigger because canvas isn't $state.

Good, it's deploying. Most layers cached since only the frontend changed.

Deployed. Let me notify Marian.

are these correct svelte 5 patterns?

Mostly yes, but there's one thing worth noting:

• $props(), $state, $derived, $effect — all correct Svelte 5 runes
• $state for bind:this on canvas — correct (and exactly what was missing before, causing the black screen)
• $effect for auto-saving to localStorage — fine
The one iffy pattern is using $effect for data fetching (the fetch() call in StemWaveformCanvas). Svelte 5 docs recommend keeping side effects like network requests outside of $effect where possible, or at least being careful about re-triggering. It works here since the only dependency is trackId, but if you wanted to be strict, an onMount + explicit trackId watcher would be more idiomatic.

Nothing broken though — the patterns are functional and correct for Svelte 5.

upload fails

API is up. Let me check the container logs for upload errors.

No errors visible. Let me get more logs.

No POST /api/tracks at all — the upload request isn't even reaching the backend. The issue is likely on the SvelteKit side. Let me check the upload page and the SvelteKit proxy.

Let me check the SvelteKit frontend logs for any errors on the upload POST.

No error logs at all. Marian might have just tried and it silently failed in the browser. Let me try uploading a test file myself.

Upload works from curl. Let me check the upload page component for JS errors.

The code looks fine. The upload goes through the SvelteKit proxy. Let me try loading the actual page in a browser to see if there's a client-side error.

Only a favicon 404 — no JS errors. Let me actually try uploading a file through the browser to see what happens.

Failed to load resource: the server responded with a status of 413 () /api/tracks

Context overflow: prompt too large for the model. Try again with less input or a larger-context model.

Reset to default 1m. Let me set it back.

413 Request Entity Too Large

nginx

That message probably crossed with my fix. It should work now — I just set nginx back to 1GB. Try uploading again.

Analysis failed
8The resource <URL> was preloaded using link preload but not used within a few seconds from the window's load event. Please make sure it has an appropriate as value and it is preloaded intentionally.Understand this warning
/api/tracks:1 Failed to load resource: the server responded with a status of 413 ()Understand this error
/api/tracks/040a8961-3b89-4daf-9a9d-65e73d4a41e9/analyze:1 Failed to load resource: the server responded with a status of 504 ()

Upload worked (got track ID 040a8961), but analysis hit a 504 gateway timeout. The nginx proxy timeout probably also got reset. Let me fix that and check if the analysis is still running.

The analysis actually completed successfully (200 OK) — nginx just timed out before the response got back. The timeouts are now fixed to 5 minutes. Let me trigger re-analysis so the frontend picks it up.

why 5 mins? make it longer

Good. i like it so far (stem waveform)
Now make stem waveform 2.0 variant (separate from this one)
• Make it reflect similar to soundcloud - bottom half scaled to half or a third. (make its size a param)
• Separate vocal to its own waveform that would appear at the top of the image. So the rest parts would be stacked, with soundcloud style reflection, and vocal waveform would hang from the top above

Cool concept. Let me build this — new stemwaveformv2 with vocals on top, stacked instrumentals with SoundCloud-style reflection below.

Now let me build both the backend renderer and frontend component.

Now the frontend Canvas component:

Now update the showcase page to add the new method and its params panel:

Now add v2 params with localStorage:

Now add the v2 canvas rendering and STEM_METHODS update:

Now add the v2 params panel:

Good progress, exporting image. Let me wait for it to finish.

Deployed. Let me also re-set the nginx timeouts since deploys reset them:

smoothing param?
add reflection to the vocal too (editable by param)
add threshold for vocal (ignore < x), because the algorithm detects like subtle vocals where there aren't any

Three changes: add smoothing, vocal reflection, and vocal threshold. Let me update the component and the params panel.

Now update the defaults and params panel in the showcase page:

Now update the v2 params panel:

Good, it's past image export and deploying now.