diff --git a/.env.example b/.env.example
index 525dba9..c8f0474 100644
--- a/.env.example
+++ b/.env.example
@@ -8,4 +8,9 @@ NODE_ENV=production
 LOG_LEVEL=info
 RATE_LIMIT_WINDOW_MS=60000
 RATE_LIMIT_MAX_REQUESTS=30
-# TRUST_PROXY=true  # Uncomment when behind reverse proxy (Traefik, Nginx) for correct client IP detection
\ No newline at end of file
+# TRUST_PROXY=true  # Uncomment when behind reverse proxy (Traefik, Nginx) for correct client IP detection
+
+# S3-compatible API credentials
+# S3_ACCESS_KEY=teleuploader-admin
+# S3_SECRET_KEY=your-secret-key-here
+# S3_DEFAULT_REGION=us-east-1
\ No newline at end of file
diff --git a/schema.sql b/schema.sql
index 22941be..52ba0a3 100644
--- a/schema.sql
+++ b/schema.sql
@@ -26,4 +26,50 @@ CREATE INDEX IF NOT EXISTS idx_files_telegram_file_id ON files(telegram_file_id)
 CREATE INDEX IF NOT EXISTS idx_files_file_hash ON files(file_hash);
 CREATE INDEX IF NOT EXISTS idx_files_archive_telegram_file_id ON files(archive_telegram_file_id);
 CREATE INDEX IF NOT EXISTS idx_files_uploader_id ON files(uploader_id);
-CREATE INDEX IF NOT EXISTS idx_files_created_at ON files(created_at DESC);
\ No newline at end of file
+CREATE INDEX IF NOT EXISTS idx_files_created_at ON files(created_at DESC);
+
+-- S3-compatible buckets
+CREATE TABLE IF NOT EXISTS buckets (
+  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+  name VARCHAR(63) UNIQUE NOT NULL,
+  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+-- Extend files table for S3
+ALTER TABLE files ADD COLUMN IF NOT EXISTS bucket_id UUID REFERENCES buckets(id);
+ALTER TABLE files ADD COLUMN IF NOT EXISTS s3_key TEXT;
+ALTER TABLE files ADD COLUMN IF NOT EXISTS storage_backend VARCHAR DEFAULT 'telegram';
+ALTER TABLE files ADD COLUMN IF NOT EXISTS is_deleted BOOLEAN DEFAULT false;
+ALTER TABLE files ADD COLUMN IF NOT EXISTS multipart_upload_id TEXT;
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_files_bucket_key ON files(bucket_id, s3_key) WHERE is_deleted = false;
+CREATE INDEX IF NOT EXISTS idx_files_bucket_prefix ON files(bucket_id, s3_key text_pattern_ops);
+CREATE INDEX IF NOT EXISTS idx_files_s3_key ON files(s3_key);
+CREATE INDEX IF NOT EXISTS idx_files_bucket_id ON files(bucket_id);
+
+-- Multipart upload tracking
+CREATE TABLE IF NOT EXISTS multipart_uploads (
+  upload_id VARCHAR PRIMARY KEY,
+  bucket_id UUID NOT NULL REFERENCES buckets(id),
+  s3_key TEXT NOT NULL,
+  initiated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  status VARCHAR DEFAULT 'in_progress',
+  initiated_by TEXT
+);
+
+CREATE TABLE IF NOT EXISTS multipart_parts (
+  id SERIAL PRIMARY KEY,
+  upload_id VARCHAR NOT NULL REFERENCES multipart_uploads(upload_id) ON DELETE CASCADE,
+  part_number INT NOT NULL,
+  telegram_file_id VARCHAR NOT NULL,
+  telegram_file_unique_id VARCHAR NOT NULL,
+  storage_message_id BIGINT NOT NULL,
+  size_bytes BIGINT NOT NULL,
+  etag VARCHAR NOT NULL,
+  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  UNIQUE(upload_id, part_number)
+);
+
+CREATE INDEX IF NOT EXISTS idx_multipart_parts_upload ON multipart_parts(upload_id, part_number);
+CREATE INDEX IF NOT EXISTS idx_multipart_uploads_status ON multipart_uploads(status);
\ No newline at end of file
diff --git a/src/env.ts b/src/env.ts
index 5fb686d..67e9d41 100644
--- a/src/env.ts
+++ b/src/env.ts
@@ -16,6 +16,9 @@ interface AppConfig {
   batchMaxItems: number;
   batchMaxSizeBytes: number;
   maxRequestBodyBytes: number;
+  s3AccessKey: string;
+  s3SecretKey: string;
+  s3DefaultRegion: string;
 }
 
 const requiredEnv = {
@@ -72,6 +75,9 @@ export const config: AppConfig = {
   batchMaxItems: parseNumber(process.env.BATCH_MAX_ITEMS, 20),
   batchMaxSizeBytes: parseNumber(process.env.BATCH_MAX_SIZE_BYTES, 500 * 1024 * 1024),
   maxRequestBodyBytes: parseNumber(process.env.MAX_REQUEST_BODY_BYTES, 2 * 1024 * 1024 * 1024),
+  s3AccessKey: process.env.S3_ACCESS_KEY || 'teleuploader-admin',
+  s3SecretKey: process.env.S3_SECRET_KEY || '',
+  s3DefaultRegion: process.env.S3_DEFAULT_REGION || 'us-east-1',
 };
 
 logger.info('Environment variables loaded', {
@@ -80,5 +86,7 @@ logger.info('Environment variables loaded', {
     botToken: maskSecret(config.botToken),
     additionalBotTokens: config.additionalBotTokens.map(maskSecret),
     databaseUrl: maskDatabaseUrl(config.databaseUrl),
+    s3AccessKey: maskSecret(config.s3AccessKey),
+    s3SecretKey: maskSecret(config.s3SecretKey),
   },
 });