AmateRS 0.2.1 Released — Zero-Warning Hygiene for a Database That Computes in the Dark

In confidential computing, a broken doc link is not cosmetic — it is a crack in the trust surface.

Today we released AmateRS 0.2.1 — a small maintenance and polish patch over 0.2.0 that clears a clippy lint, fixes a broken intra-doc link in the MerkleTree documentation, and runs cargo fmt across the server hot-reload and main modules.

No C. No Fortran. No SEAL or OpenFHE bindings dragged in through a forest of -sys crates. AmateRS is 100% Pure Rust by default, licensed under Apache-2.0. Serialization runs through oxicode instead of bincode, and the only bincode anywhere is feature-gated behind the TFHE serialization path. It still compiles to a single static binary you drop onto a server and run. Like Amaterasu sealed in the Heavenly Rock Cave (Iwato), your data stays inside a cryptographic shell while the computational light keeps shining.

Why 0.2.1 matters

For a database whose entire promise is that the server never sees your plaintext, documentation accuracy and a clean lint slate are not housekeeping — they are part of the trust contract. If the integrity internals are documented with dangling links, or the workspace carries clippy noise that hides the next real warning, the people auditing the thing have less reason to believe the cryptography underneath it was held to the same bar.

So we hold the bar everywhere:

• A clean cargo clippy across the workspace, with no doc_lazy_continuation lint lingering in the cluster key-retention configuration docs.
• Accurate MerkleTree documentation, so the integrity and anti-entropy internals are correctly cross-linked instead of pointing at a dead reference.
• Consistent formatting in the server hot-reload and main modules, so diffs stay about behavior and never about whitespace.

That is the whole release. No new features, no new API — just the discipline that keeps a confidential-computing database trustworthy.

Technical Deep Dive

The architecture is unchanged from 0.2.0. AmateRS is still organized into four components, each named after a piece of the Amaterasu myth: Iwato (岩戸), the LSM-tree storage engine; Yata (八咫鏡), the FHE compute engine; Ukehi (宇気比), the Raft consensus layer; and Musubi (結び), the gRPC network layer. 0.2.1 touches none of their behavior — it only sharpens the edges around them.

Where the polish landed:

• Cluster key-retention config docs. A doc_lazy_continuation clippy lint was resolved in a configuration doc comment, bringing that surface back under the project’s zero-warning bar.
• MerkleTree documentation. A broken intra-doc link that pointed at the private empty_root function was fixed, so the docs for a type that AmateRS uses for integrity and anti-entropy now render their references correctly.
• Server hot-reload and main modules. A cargo fmt pass normalized formatting across these modules.

Nothing beyond those three changes was touched.

Getting Started

0.2.1 is a drop-in patch over 0.2.0, so adoption is just a version bump. Add the facade crate and start the server exactly as before.

# As a library dependency (patch release)
cargo add amaters     # resolves to 0.2.1

# Start the server
cargo run --bin amaters-server -- start --data-dir ./data

Since there is no new API to demo, the most fitting thing to exercise in this release is the discipline it embodies — a clean dev loop that matches the project’s own quality gate:

# Match the project's zero-warning bar
cargo clippy --workspace --all-features -- -D warnings

# Read the now-correctly-linked MerkleTree docs
cargo doc --no-deps --open

And the everyday set/get path is exactly where it was — connect with the Rust SDK and read and write a key:

use amaters_sdk_rust::AmateRSClient;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let client = AmateRSClient::connect("http://localhost:7878").await?;

    client.set("my_key", "encrypted_data").await?;
    let value = client.get("my_key").await?;
    println!("{value:?}");

    Ok(())
}

What’s New in 0.2.1

• Resolved a doc_lazy_continuation clippy lint in a cluster key-retention configuration doc comment.
• Fixed a broken intra-doc link to the private empty_root function in the MerkleTree documentation.
• Applied a cargo fmt cleanup across the server hot-reload and main modules.

Tips

• Match the project’s zero-warning bar. Run cargo clippy --workspace --all-features -- -D warnings in your own checkout — it is exactly the gate AmateRS holds itself to, and it turns a stray lint into a build failure before it ships.
• Read the fixed MerkleTree docs. cargo doc --no-deps now renders the integrity and anti-entropy references without the dead empty_root link — a good entry point for understanding how AmateRS reasons about consistency.
• Pin amaters = "0.2.1" with confidence. It is a drop-in patch over 0.2.0 with no API changes and nothing to migrate; the upgrade is a one-line version bump.
• Keep cargo fmt --all in your pre-commit. This release is partly a formatting normalization; wiring cargo fmt --all -- --check into your hooks keeps your own diffs about behavior, not whitespace.

This is the foundation

AmateRS is the confidential-computing layer of the COOLJAPAN ecosystem, and by May 2026 its ties are concrete: serialization runs through oxicode, our Pure Rust replacement for bincode, and compression goes through OxiARC — so AmateRS inherits the same no--sys, no-C posture as the rest of the stack. A patch like 0.2.1 is the unglamorous half of that promise: keeping every surface clean so the cryptography underneath stays the only thing you have to think hard about.

Repository: https://github.com/cool-japan/amaters

Star the repo if a database that never sees your plaintext — and is held to a zero-warning, docs-clean bar — is the kind of thing you have been waiting for.

Sovereign by default, clean to the last lint.

— KitaSan at COOLJAPAN OÜ May 9, 2026