Response Compression

Lambda Web Adapter supports gzip and Brotli compression for response bodies in buffered mode.

Enabling Compression

AWS_LWA_ENABLE_COMPRESSION=true

Behavior

When enabled:

• Responses are compressed using gzip or Brotli based on the client's Accept-Encoding header
• Responses with Content-Type starting with image are not compressed
• Responses smaller than 32 bytes are not compressed

Limitations

Compression is not supported with response streaming (AWS_LWA_INVOKE_MODE=response_stream). If both are enabled, compression is automatically disabled and a warning is logged.