A self-hosted file sharing app in a single PHP file. No framework, no Composer dependencies, no database.

• Upload files into optional folder paths
• Public or private visibility per file
• Configurable expiry (1h – 30d, or never)
• Automatic expiry cleanup via a cron endpoint
• CSRF protection on all mutating actions
• Bcrypt password hashing, session fixation protection, brute-force delay
• Content-Security-Policy and X-Content-Type-Options headers

• PHP 8.2+ with the fileinfo extension
• Nginx (or Apache) — see configuration below

git clone <repo> fileshare
cd fileshare
cp .env.example .env

Edit .env:

USERNAME=admin

# Generate a bcrypt hash for your password:
# php -r "echo password_hash('yourpassword', PASSWORD_BCRYPT);"
PASSWORD=$2y$12$...

# Generate a random cron secret:
# php -r "echo bin2hex(random_bytes(32));"
CRON_SECRET=...

Create the required directories and make them writable by the PHP-FPM user:

mkdir -p uploads data
chown www-data: uploads data   # replace www-data with your PHP-FPM user if different

composer serve
# → http://localhost:8000

src/
  index.php       — bootstrap, constants, router
  handlers.php    — route handlers and view renderers
  helpers.php     — env loading, metadata I/O, path and output utilities
  router.php      — PHP built-in server router (dev only)
  simple.min.css  — Simple.css (local copy)
  views/
    login.php     — login page
    dashboard.php — file management dashboard
uploads/          — uploaded files (mirrors user-supplied folder structure)
data/
  files.json      — file metadata (path, private, expires, uploaded)
  .lock           — flock coordination file (created automatically)
.env              — credentials and secrets (not web-accessible)

server {
    listen 443 ssl;
    root /path/to/fileshare/src;

    # Match the application's 50 MB limit
    client_max_body_size 50M;

    # HSTS — remove max-age line and re-deploy if you ever need to revert to HTTP
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains" always;

    location / {
        try_files $uri $uri/ /index.php$is_args$args;
    }

    location ~ \.php$ {
        fastcgi_pass unix:/run/php/php8.2-fpm.sock;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }
}

Checklist before going live

• Set client_max_body_size to match MAX_UPLOAD_BYTES (50 MB)
• Enable TLS and configure the ssl_certificate / ssl_certificate_key directives
• Add the Strict-Transport-Security header only after TLS is confirmed working
• Confirm uploads/, data/, and .env are outside the Nginx root
• Confirm uploads/ and data/ are writable by the PHP-FPM user (chown www-data: uploads data)
• Set upload_max_filesize = 50M and post_max_size = 52M in php.ini

Set up a system cron to trigger expiry cleanup. The CRON_SECRET from .env is required as a query parameter:

# Run expiry cleanup every hour
0 * * * * curl -s "https://example.com/cron?secret=<CRON_SECRET>"

• uploads/, data/, and .env are outside the webroot and not served by Nginx
• All file paths are validated with realpath() against UPLOADS_DIR to prevent path traversal
• Passwords are stored as bcrypt hashes; login has a 300 ms fixed delay against brute force
• Session ID is rotated on login to prevent session fixation
• The cron endpoint is protected by a secret compared with hash_equals() to prevent timing attacks
• CSRF tokens are required on all POST forms