Sendless
Secure, serverless file transfer that runs in your own AWS account.
Send files with expiring, password-protected links. Collect files from people who have no account.
No servers to run, nothing leaves your account, and one click to deploy.
- Fully serverless. CloudFront, Lambda, S3, DynamoDB and Cognito. Nothing to patch or scale, and close to zero cost when idle.
- One-click deploy. A single CloudFormation template that works in any commercial AWS Region, with no us-east-1 dependency and no Lambda@Edge.
- Your data stays put. Files, metadata and logs stay in the Region you deploy to. There is no phone-home, and the license check runs offline.
- Recipients need no account. Senders sign in with Cognito, or with your company login on Pro.
Features
| Community (Apache-2.0) | Pro |
|---|
| Send files with expiring links (time and/or number of opens) | ✓ | ✓ |
| Password protection with brute-force lockout | ✓ | ✓ |
| Large files: resumable multipart uploads straight to S3, up to 5 TB per file | ✓ | ✓ |
| File requests: let anyone upload files to you, without an account | ✓ | ✓ |
| Email the link and get notified on download (Amazon SES) | ✓ | ✓ |
| Activity log per transfer (who opened, which file, IP, country) | ✓ | ✓ |
| Privacy and imprint links | ✓ | ✓ |
| User management, invitations, optional self sign-up by email domain, two-factor authentication with an authenticator app | ✓ | ✓ |
| Guaranteed deletion: sweeper plus an S3 lifecycle hard limit | ✓ | ✓ |
| English and German UI, light and dark theme | ✓ | ✓ |
| Single sign-on (SAML / OIDC: Entra ID, Okta, Google, …) | | ✓ |
| Malware scanning with GuardDuty, downloads blocked until clean | | ✓ |
| Audit log for the whole installation with CSV export | | ✓ |
| Policies: mandatory passwords, maximum lifetime, blocked file types, allowed recipient domains | | ✓ |
| Branding: your name, logo, colors, welcome and footer texts | | ✓ |
Deploy
- Open the Launch stack link for the release you want, or create a stack from
sendless.yaml in the CloudFormation console. Choose any Region.
- Enter the administrator email. Everything else is optional: email sending, custom domain, self sign-up, malware scanning.
- Wait about 5 minutes. The administrator receives a temporary password by email. Open the
AppUrl from the stack outputs and sign in.
To remove Sendless, delete the stack. The buckets are emptied first, so nothing is left behind.
See docs/deployment.md for parameters, custom domains, email, upgrades and publishing your own release.
How it works
Browser ──HTTPS──▶ CloudFront ─┬─▶ S3 (web app, via OAC)
│ └─▶ Lambda function URL (/api/*, via OAC + IAM)
│ ├─ DynamoDB (transfers, requests, audit)
│ ├─ Cognito (senders, admins, SSO)
│ └─ SES (optional email)
└──presigned PUT/GET──▶ S3 (files, private, encrypted, lifecycle-limited)
EventBridge ──every 15 min──▶ sweeper Lambda (deletes expired files)
File bytes never pass through Lambda: browsers upload parts straight to S3 with presigned URLs and download the same way. The API function can only be reached through this CloudFront distribution. The full reasoning is in docs/architecture.md.
Develop
npm install
npm run dev # http://localhost:5173 — runs the real API with in-memory adapters, no AWS account needed
npm run dev:pro # same, with Pro features unlocked by a throwaway development license
npm test # unit, service and store contract tests
npm run typecheck
npm run release -- --base-url https://<bucket>.s3.amazonaws.com/sendless
Sign in locally as [email protected] or [email protected] (no password in dev mode). See docs/development.md.
Repository layout
template/sendless.yaml CloudFormation template (the one-click deployable)
packages/shared API types and validation shared by backend and frontend
packages/api Lambda handlers, services, AWS and in-memory adapters, dev server
packages/web React single-page app
ee/ Pro features, under the Sendless Enterprise License
scripts/ dev, build, release, publish
docs/ architecture, deployment, development, selling
License
Everything outside ee/ is licensed under the Apache License 2.0.
The ee/ directory contains the Pro features and is licensed under the Sendless Enterprise License: you may read and modify it, but using Pro features in production requires a valid license key.
Copyright © 2026 SilverLining.Cloud GmbH.
