SL-Files · Backup & Seal
SL-Files copies camera media to two or three backup drives in a single read, verifies every byte past the disk cache, and seals each transfer with a certificate you can hand to production. Offline, no account.
Launching on the Mac App Store — in reviewFree download · Verify free forever · first 100 GB of offloads free
Runs natively on Apple Silicon and Intel Macs · macOS 13 or later
What it does
Ten things SL-Files does on the cart, in one offline app — not a subscription stack plus a scatter of free side-tools.
Pick a source card and up to three destinations. SL-Files reads the card once and fans the copy out to every drive at the same time — no extra wear on the media.
Every file is checksummed on the way in and re-read byte-for-byte on the way out, past the macOS disk cache — so a failing card, reader or cable is caught, not trusted.
For original camera media, SL-Files re-reads the source itself, not just the copies — the strongest guarantee you can give before a card is ever wiped.
Choose your checksum. The progress bar runs red to green and only reaches green once every byte has been verified.
On every destination, beside your footage: a classic MHL, an ASC MHL manifest with a tamper-evident chain (the ASC/MITC standard some studios now require), and a machine-readable JSON sidecar.
Each offload produces a seal certificate — route, payload, operator, machine, checksum method and full per-file manifest — exportable as a PDF report you hand to post.
Point SL-Files at a backup made by another tool and it re-checks every file against the drive's own manifest — no copy required. It reads MHL and ASC MHL written by Silverstack, ShotPut Pro, YoYotta and Resolve.
SL-Files recognises original camera media and treats it with the extra care an irreplaceable source deserves.
See what macOS knows about every connected drive — SMART status, bus, capacity — before you trust it with a day's work.
No account, no internet, no phone-home. Everything runs on a laptop in a valley with no bars.
Free to try
Enough to run a real card through copy, verify and seal on a real shoot — before you pay a cent.
The Verify screen reads any tool's MHL or ASC MHL — Silverstack's, ShotPut's, YoYotta's — and re-checks a backup byte for byte. It never expires and never counts against your allowance.
Run a real card through copy → verify → seal before deciding. The allowance is metered on-device; the engine never interrupts a transfer already in flight.
One in-app purchase lifts the cap. Everything you sealed on the free tier stays valid — nothing to re-run, nothing to migrate.
Pricing
Less than one day of your rate — once. Software is a rounding error beside the kit you re-bill to production.
The App Store edition is billed by Apple under Apple's terms. SL-Files Pro (direct) and Silverlines plans are billed by Korner Studio Sàrl. Verifying a backup is always free.
Questions
What DITs ask us most about SL-Files.
SL-Files 1.0.0 has been submitted to the Mac App Store and is in review. Leave your email above and we'll write the day it goes live — the download is free.
Verifying an existing backup is free forever, and so are your first 100 GB of offloads — enough to run a real card through copy, verify and seal before you decide.
Unlimited offloads unlock with a one-time purchase of $99.99 or a $19/month subscription, right in the app. Apple handles billing and refunds; the subscription renews monthly unless you cancel it at least 24 hours before the period ends.
Yes. Point SL-Files at a backup made by another tool and it re-checks every file against the drive's own MHL or ASC MHL manifest — no copy required. It reads manifests written by Silverstack, ShotPut Pro, YoYotta and Resolve. Verifying is free, forever.
Pro is the direct edition (coming soon) that adds a gated card erase and native volume encryption with crypto-erase on top of everything in the App Store edition. The erase runs only behind a seal check, a typed name and your macOS password. Silverlines Producer and Studio subscribers get Pro included today.
No. SL-Files runs entirely offline with no account and no phone-home. Signing in is optional — only to confirm a sealed backup to a production that runs on Silverlines, and even then only metadata is sent, never footage.
The App Store edition runs natively on Apple Silicon and Intel Macs, macOS 13 or later.
Get an email the day SL-Files lands on the Mac App Store — free to download.
Notify me at launch