dig-capsule

The DIG capsule data plane — the .dig / DIGS format, the compiler that builds a capsule from files, the capsule read-crypto, staging, the guest/host serve triad, and the capsule size ladder. A capsule is the DATA portion of a store; the on-chain anchor (singleton, storeId, generations) lives in dig-store, which depends on this crate.

Depend on just dig-capsule

dig-capsule is ONE crate with a curated facade (src/lib.rs): one clean public API over feature-gated modules. The internal split lives under src/imp/ and is an implementation detail — you use the concept modules, never reach into the internals. The whole .dig format-manager API is learnable from this crate's docs alone.

[dependencies]
dig-capsule = "0.4"                                   # the whole API (default = full)
# slim readers (e.g. a URN resolver) take base only (+ `std` for the urn scheme):
# dig-capsule = { version = "0.4", default-features = false, features = ["std"] }

use dig_capsule::prelude::*;

let spec = CapsuleClass::DEFAULT.spec();              // 128 MB, the canonical size
// The canonical URN (owned by `dig-urn-protocol`, re-exported through the facade):
let urn = DigUrn::parse("urn:dig:chia:0000000000000000000000000000000000000000000000000000000000000000").unwrap();
let key = urn.content_key();                          // frozen root-independent key derivation

The concept modules: capsule, urn, format, merkle, chunk, metadata (base); crypto, store, compile, stage, host, prover, guest (feature-gated). See the crate rustdoc (cargo doc --open) for the full re-export map.

Feature flags

Feature	Enables	Typical consumer
(base)	no_std+alloc: format / merkle / chunk / metadata — no wasmtime, no blst, no getrandom	slim embedded readers
std	lifts out of no_std; adds the canonical urn scheme + chunk::chunk_stream	dig-urn-resolver (default-features = false, features = ["std"])
default = ["full"]	crypto + store + compile + serve — the whole API	dig-store, dig-node
crypto	native AES-256-GCM-SIV AEAD + Chia-BLS (implies std)
store	on-disk generation / staging model (implies crypto)
compile	files→capsule pipeline (implies store + crypto)
serve	blind serve triad + serving proofs (implies crypto)
wasm	the browser/Node read-crypto surface (@dignetwork/dig-capsule-wasm)
guest-wasm	the self-serving guest cdylib compiled to wasm32	build.rs guest embed
risc0	the real RISC0 serving-proof circuit (OFF by default; needs the RISC0 toolchain)

The browser counterpart

The browser + Node read-crypto is NOT a Rust dependency: it is the @dignetwork/dig-capsule-wasm npm package, whose surface (reconstructUrn, retrievalKey, deriveKey, verifyInclusion, decryptResource, decryptResourceToText, readPublicManifest, version) is installed on globalThis.digClient. It produces byte-identical KDF/AEAD/URN/merkle output to the native crypto module here.

Layout (implementation detail — use the facade modules, not these)

The internal split lives under src/imp/ and is a pub(crate) implementation detail; the top-level facade modules (capsule, format, merkle, chunk, metadata, urn, crypto, store, compile, stage, host, prover, guest) are the public surface.

• src/imp/core — DIGS format/datasection, capsule identity, codec, sizes, chunk-seal
  • KDF crypto, keytable, manifest, merkle, wire, ABI (no_std/wasm-clean). The urn:dig: scheme is NOT here — it is the canonical dig-urn-protocol crate, re-exported through the facade urn module (requires std).
• src/imp/chunker — content chunking.
• src/imp/crypto — AEAD + chia-bls signing + serving-proof crypto (native, crypto).
• src/imp/store — chunkstore / generation / history / staging / diff (store).
• src/imp/guest, src/imp/host, src/imp/prover — the guest/host serve triad + §13 serving proofs (ChainSource + CoinsetChainSource) (serve/host).
• src/imp/compiler, src/imp/stage — files → self-serving capsule module + the stage → compile build pipeline (compile).
• src/wasm_browser.rs (the wasm feature) — the browser + Node read-crypto behind the @dignetwork/dig-capsule-wasm npm package, built with wasm-pack build --no-default-features --features wasm (packaging harness in wasm-npm/).
• guest-risc0/ — the RISC0 serving-proof guest, a NESTED non-published package built only under risc0 (referenced via [package.metadata.risc0]).

Docs

• SPEC.md — the normative data-plane contract.
• runbooks/ — build, test, and publish procedures.

Licensed GPL-2.0-only.