Privacy Policy

We collect the minimum needed to run an audio diagnostics tool:

• Account info — email, display name, hashed password, plan tier, Stripe customer ID. You give us these when you sign up or upgrade.
• Uploaded audio — the files you upload for analysis or as references. Stored in Cloudflare R2 with signed-URL access only (never publicly listed).
• Analysis data — score, diagnostics, metrics, applied corrective steps, render history. This is the value you came for; it persists.
• Usage telemetry — anonymized page views, feature interactions, and error reports via PostHog and Sentry. No keystroke logging, no recording.
• Cookies — a session cookie for auth, a CSRF token cookie for write requests, and optional analytics cookies (you can decline these).

Uploaded audio flows straight to R2 via signed PUT — your audio bytes never sit on our application servers longer than the upload itself. Our analysis worker reads the file from R2, computes metrics (LUFS, true peak, spectrum, stereo, dynamics), runs the rules engine, and persists the analysis row. The audio is then retained according to your plan:

• Free plan: audio deleted 24 hours after upload.
• Pro / Studio plans: audio deleted 30 days after upload.

The retention reaper runs daily and is best-effort within a few hours of the cutoff. Once deleted, the audio file is gone — we can't recover it. Your analysis row (score, diagnostics, render history) stays in your history; only the source audio is removed.

We do not train AI models on your audio. We do not fingerprint it for identification. We do not resell it. We do not run automated content moderation on it beyond technical analysis. Audio sent to MixLens is audio used to produce your score and your corrective render output, and nothing else.

We use a small set of vendors to deliver the product. Each only sees the slice of data they need:

• Cloudflare R2 — object storage for audio and rendered output. Signed URLs only.
• Railway — application hosting (web, worker, beat, frontend). Standard PaaS access to our database and Redis.
• Stripe — payment processing. Stripe holds your card; we never do. We store only your Stripe customer ID and the resulting subscription state.
• Sentry — error reporting. Sentry receives stack traces and request metadata scrubbed of PII; it does not receive your audio.
• PostHog — product analytics. PostHog receives anonymized usage events; you can disable it via your browser's Do-Not-Track / analytics opt-out.
• Email provider — transactional emails (welcome, analysis-ready, render-ready, billing). Receives your email address and the message contents.

We do not share or sell your data to advertisers, data brokers, model trainers, label A&R desks, or any other third party not listed here.

If you create a webhook at /account/webhooks, MixLens will POST signed JSON payloads to the URL you provide when subscribed events fire (e.g. analysis.complete, render.complete). The contents of those payloads are described in our webhooks documentation. Once your webhook endpoint receives the payload, it's in your hands — our privacy practices end at our boundary.

• All traffic is HTTPS. R2 stores audio at rest with provider-level encryption.
• API tokens and webhook secrets are stored as SHA-256 hashes; we cannot recover them after creation.
• Database is hosted on Railway with managed backups.
• We follow standard credential hygiene (env-var secrets, no shared credentials in code).

If you discover a vulnerability, please email security@mixlens.io. We'll respond within two business days.

Regardless of where you live, you can:

• Access the personal data we hold about you.
• Correct anything that's wrong.
• Delete your account and associated data.
• Export your analysis history.
• Withdraw consent for marketing emails at any time via /account/email-preferences.

To make any of these requests, email privacy@mixlens.io. We respond within 30 days.

If you're in the EU, UK, or California, you have additional rights under GDPR, UK GDPR, and the CCPA respectively. Same email reaches the same person; same 30-day window applies.

MixLens is not directed at children under 13. We don't knowingly collect data from anyone under 13; if you believe we have, email privacy@mixlens.io and we'll delete the account.

We'll update this policy when our practices change. Material changes (new vendor categories, retention changes, new data we collect) trigger an email to active accounts. Cosmetic changes (rewording, fixing typos) just update the date above.

For privacy questions, email privacy@mixlens.io. For everything else, hello@mixlens.io.