The State of Sia, April 2026

April was a launch-focused month for the Sia Foundation as the team prepared for the Sia Storage App debut at Consensus Miami. The app brings fully private, user-owned cloud storage to the Sia network with 50 GB free and no crypto knowledge required, making it one of the clearest expressions yet of Sia’s mission to make decentralized storage accessible to everyday users. The Foundation also finalized its 2026 Social Media Strategy, positioning Sia as an educational voice on data privacy.

The grants program saw one new approval, SiCal, and two final progress reports. Chi-Voice completed its pilot work by switching from Zen to Mainnet and testing its REST API on Mainnet, while SMB Indexer Support completed its grant scope by enabling uploads and downloads through an indexd-backed share.

Development Updates

indexd: Lower Contention, Faster Downloads & Better App Storage Awareness

Development on indexd this month focused on reducing database contention, improving download performance, and giving apps better visibility into their available storage. These updates continue to support indexd’s role as a simpler, more developer-friendly layer for building on Sia.

Stats handling was refined by using deltas and treating each stat as a separate row, reducing contention.
Downloads now use parallelism to improve performance and time to first byte.
Apps can now see a remaining storage field in app responses, helping them track available storage.
Slab migration benchmarks were added, while older benchmarks were fixed after schema changes.
The account fund interval was reduced to 15 minutes, shrinking the initial fund for new accounts and reducing wait time before high-usage accounts refill.

sia-storage-sdk: Cleaner Examples, Updated Bindings & Better Documentation

Work on sia-storage-sdk focused on improving the developer experience around the Sia Storage SDK bindings. The updates made examples more consistent, refreshed the SDK against the latest Rust implementation, and improved documentation for developers getting started.

Examples and wrappers were made more consistent across supported languages.
The SDK was updated to the latest sia-sdk-rs.
Object pinning examples were added in different languages.
A main README and Python-specific README were added.

sia-sdk-rs: Faster Uploads, Stronger Browser Support & More Reliable Transfers

sia-sdk-rs saw a broad set of improvements across upload performance, host management, browser compatibility, transfer callbacks, and timeout behavior. These changes improve both low-level reliability and the experience of building apps on the Rust SDK.

The hosts list now refreshes periodically rather than being retrieved only at startup.
The upload path was refactored into a single-use pipeline, improving benchmarked throughput by roughly 5–6%.
Upload and download progress handling was unified around callbacks.
Timeout behavior was overhauled, with three retries per host and a longer default timeout per shard attempt.
Concurrent dials to the same host are now deduplicated, and WebTransport connection behavior has been adjusted to stay within Chrome’s pending-connection limit.
Safari browser uploads were fixed by adding a fallback path for default ReadableStreams when zero-copy BYOB reading is unavailable.
PackedUpload was refactored on native to fix a data corruption bug in erroneous reads and prevent errors from being swallowed.

No standalone UI changes were noted for sia-sdk-rs, though the Safari upload fix directly improves browser-based app reliability.

hostd: Constant-Time Contract Renewals & Renewal Reliability

hostd v2.8.0 shipped this month with important contract renewal improvements, dependency updates, and fixes for renewal reliability after resyncs. The release also included a graceful shutdown improvement for the RHP4 server.

Contract renewals and refreshes are now constant and no longer need duplicate sector roots.
RHP4 server shutdown now happens gracefully via defer .Close().
A bug that caused renewals to fail after a resync was fixed.
go.sia.tech/core was updated to v0.20.0 and go.sia.tech/coreutils to v0.21.3.
hostd now uses the new contract-not-found error when it is not aware of a contract.

On the UI side, hostd v2.8.0 fixed a mismatch between the host’s announced address and the address displayed in the UI for hosts that had a different address before the hardfork.

coreutils: Safari WebTransport Compatibility for RHP4

coreutils received an important compatibility update for Safari’s WebTransport behavior. This helps ensure RHP4’s WebTransport server remains reachable across more browser environments.

RHP4’s WebTransport server was made reachable from Safari 26.4.
Additional Safari-required settings were added because webtransport-go v0.10.0 does not yet advertise them.

renterd: Renewal Fixes, Smoke Tests & Safer Contract Pruning

renterd v2.9.1 focused on stability and correctness, especially around contract renewals and pruning behavior.

A bug that prevented contracts from renewing due to invalid signatures was fixed.
An edge case where pruning a contract could delete the wrong sector was resolved.

Grant Program Updates

Newly Approved Grants

SiCal: SiCal is a decentralized calendar app built with Flutter and Rust that uses the sia_storage SDK to save calendar data to Sia. The app stores data locally in SQLite first, then syncs to Sia using packed uploads for small calendar events. The grant supports a two-month push to complete core calendar functionality, including onboarding, event creation, recurring events, .ics imports, notifications, support for multiple calendars, app store publishing, and community feedback.

Progress Reports from Ongoing Grants

Sia NFS Gateway: The project completed work on sia-io, a library that sits between indexd and/or renterd and higher-level consumers. Milestone 1 delivered support for both renterd and indexd, an abstraction layer over both backends, multi-layer caching, chunking, and I/O scheduling. Next up is the sia-vfs crate, which includes read-only and read-write filesystem modes, SQLite-backed, reconstructible local state, a write-ahead log, overlays, and an AsyncRead + AsyncWrite + AsyncSeek file interface.
Vup Vault - Personal Backup, Sync & Archive: Vup Vault completed Milestone 3, delivering end-to-end multi-device sync and sharing. A second device can now restore a vault from a remote relay using only the vault's paper recovery key, with full cryptographic verification. The project also introduced a v3 registry schema, convergent publishing, a refined vup +<vault> <verb> CLI grammar, daemon-owned FUSE mounting, frozen anonymous share links, and snap --watch support. Next month’s work begins with Milestone 4, an s5_store_indexd crate implementing the S5 Store trait against the indexd SDK.

Final Progress Reports

Chi-Voice: Chi-Voice completed its pilot by switching from Zen to Mainnet and testing API functionality on Mainnet. The team validated REST API access for Ibibio word recordings, returning signed URLs for 10 out of 10 test recordings. The project also addressed duplicate recordings, task-generation errors, and S5 credential exposure, while reinforcing the importance of early API design for external consumers.
SMB - Indexer Support: SiaSMB completed its grant scope by enabling uploads and downloads through an indexd-backed share, addressing reviewer feedback, and deploying a public test server. The final milestone included upload/download support, improved error handling, safer password handling, optimized background upload behavior, and added test coverage. The project can now connect to an indexer and interact directly with Sia hosts for file uploads and downloads.

Final Thoughts

April was a strong month for both product readiness and infrastructure maturity. The Sia Storage App launch preparations brought Sia’s user-owned data message into sharper focus, while the Foundation’s updated social and community strategy helped make that message easier to find and follow. At the protocol and tooling layer, improvements to indexd, SDKs, hostd, coreutils, and renterd strengthened the developer and user experience across performance, reliability, browser support, and contract handling.

The grants program also continued to show the breadth of what can be built on Sia. From privacy-focused calendars and NFS gateways to personal backup tools, endangered-language preservation, and SMB-compatible storage, the ecosystem is steadily expanding beyond infrastructure into practical, user-facing applications.

That’s all, folks!

Thanks for your continued support and dedication as we build the foundation of the decentralized future.

Take care, and see you next month.

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