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us is an alternative interface to the Sia network. It provides low-level, developer-oriented APIs and formats that facilitate the storage and retrieval of files on Sia.

"Low-level" means that us generally avoids making decisions on behalf of the user. For example, when renting storage, the user must decide which hosts to form contracts with, how many coins to spend on each contract, when to renew contracts, when to migrate data to new hosts, etc. These questions do not have simple answers; they vary according to the context and goals of the user. Recognizing this, the us philosophy is to provide the user with a set of building blocks rather than a one-size-fits-all solution.

Why should I care?

The us project is at the forefront of Sia research and development, exploring new ideas, tools, and protocols that complement and extend the existing ecosystem. With us, you can do things currently not supported by siad, such as:

  • Specify exactly which hosts you want to use
  • Share your files and/or contracts with a friend
  • Upload your meme folder without padding each file to 4 MiB
  • Mount a virtual Sia filesystem with FUSE
  • Upload and download without running a Sia full node

More importantly, you can use us to build apps on Sia. Here are a few ideas:

  • A storage backend for go-cloud, upspin, or minio
  • A site where you can buy contracts directly, paying with BTC (via LN?) instead of SC
  • A cron job that downloads 1 KB from a host every 24 hours and reports various metrics (latency, bandwidth, price)
  • A site that aggregates host metrics to provide a centralized host database (done!)
  • A mobile app that stores and retrieves files stored on Sia (done!)

What do I need to get started?

If you're a renter, you're probably looking for user, a CLI tool for forming contracts and transferring files that leverages the us renter packages.

If you're a hodler or an exchange, you're probably looking for walrus, a high-performance Sia wallet server that leverages the us wallet packages.

If you're a developer who wants to build something with us, please get in touch with me via email, reddit, or Discord (@nemo).

If you would like to contribute (thank you!), please read

Please be aware that us is in an experimental, unstable state. us contracts and files differ from the corresponding siad formats, so you should not assume that contracts formed and files uploaded using us are transferable to siad, nor vice versa. Until us is marked as stable, don't spend any siacoins on us that you can't afford to lose.