AWS has recently released File Mover Express, an open-source application under the Apache 2.0 license for transferring large files between local systems and Amazon S3. Available for macOS, Windows, and Linux, it supports parallel transfers, automatic performance tuning, retries, and resume, and file integrity verification.
Designed to "move media to S3 at wire speed," File Mover Express supports auto-tuned parallel transfers, and resume, a desktop GUI, a scriptable CLI, and automatic uploads from monitored folders.
The project is primarily developed in Go for its transfer engine and TypeScript with Angular for its graphical interface. It also supports integration with AI assistants through MCP and OIDC-based authentication with identity providers. Provanshu Dey, senior solutions architect at AWS, Asbjorn Kjaer, senior software engineer at AWS, Matthew Muccio, solutions architect at AWS, and Ross Dickson, senior customer solutions manager at AWS, explain:
At the core of File Mover Express is a daemon-based transfer engine that decouples transfers from your desktop session. The daemon can run on the machine of your choice, whether that is your workstation, a server in the data center, or an Amazon Elastic Compute Cloud (Amazon EC2) instance, while you control it from a drag-and-drop graphical user interface (GUI) or a scriptable command line interface (CLI) over an encrypted, password-protected connection.
Media teams regularly transfer terabytes of assets between on-premises storage and the cloud. These transfers often involve tight deadlines and processes that must continue after the initiating user or machine disconnects. Traditional transfer clients may stop when a desktop session ends, while commercial alternatives can introduce licensing costs, proprietary protocols, or third-party infrastructure. File Mover Express supports uploads and downloads, allowing teams to transfer large files to Amazon S3 and retrieve them for editing, review, or restoration.
Source: GitHub project
File Mover Express splits large files into chunks and uploads them in parallel using multipart uploads. With the autotuning mode, it adjusts the number of parallel streams and chunk sizes to optimize throughput for the available connection. Transfers also support configurable retries and file-level and resume. Dey, Kjaer, Muccio, and Dickson add:
File Mover Express provides security features including file encryption in flight, file encryption at rest, and encryption for the control plane. All transfers use HTTPS, and access to your S3 buckets is governed by AWS Identity and Access Management (IAM) with a documented minimum-permission policy (...) For teams that centralize identity, File Mover Express supports single sign-on through OpenID Connect (OIDC).
File Mover Express calculates checksums in the background and caches them locally for reuse when files remain unchanged. It supports MD5, XXHash, XXHash64, and XXH3, offering a choice between compatibility and hashing performance. For transfers to distant buckets, users can enable S3 Transfer Acceleration, while bandwidth limits help control network usage. On LinkedIn, Dickson writes:
Moving large media files to the cloud shouldn't be the slow part of your day :) That’s why a group of us at AWS built File Mover Express (...) For anyone in media moving camera cards, dailies, or deliverables, it tackles the usual pain.
The project's source code is available on GitHub, along with pre-built packages for macOS, Windows, and Linux.