TSUNAGI — 繋ぎ
The cockpit of a Cardano validator.
A 20 MB Zig node that exposes its own forge-time decision model — posterior, expected value, Kelly, and LLR — in real time.
Built on Musubi (結び): connection as a generative force. Operator-first. Deterministic. Honest.
Let It Run. Let It Resolve.
Follows the chain via Ouroboros ChainSync and BlockFetch. Admits transactions through a six-gate hardened mempool. Serves and ingests transactions via bidirectional TxSubmission2. Computes a signed eight-layer trust graph from runtime observations. Deterministic. Verifiable. No garbage collector. No runtime allocator.
Position in the ecosystem
| Node | Language | Binary Size | Decision Metrics |
|---|---|---|---|
| TSUNAGI | Zig | 20 MB | Yes |
| cardano-node | Haskell | 300–500 MB | No |
| Amaru | Rust | 50–80 MB | No |
| Dingo | Go | 50–100 MB | No |
Omotenashi in Engineering
In Japanese culture, omotenashi (おもてなし) means anticipating the needs of the recipient before they are expressed.
TSUNAGI is built the same way:
- Every forge decision is visible
- Every system state is explicit
- No hidden behavior, no silent assumptions
The operator sees exactly what the node sees.
Decision Model (Live)
TSUNAGI logs its decision metrics for every leader slot:
- Posterior probability
- Expected Value (EV)
- Kelly allocation
- Log-Likelihood Ratio (LLR)
Correlation data (in progress):
When LLR ≥ 0.5 → acceptance rate: — When LLR ≤ -0.5 → acceptance rate: — (collecting live data)
TSUNAGI is a complete Cardano node built from scratch in Zig — no Haskell dependency, no IOG codebase fork. It follows the live chain, decodes blocks, tracks UTxO state, and has proven ChainSync interoperability with real cardano-node relays. Learn more →
Independent Engineering
Real infrastructure work, transparent progress, no institutional dependencies.
TSUNAGI is an independent implementation effort — a deterministic Cardano node architecture written in Zig from scratch. The project began as a solo engineering effort to build node infrastructure grounded in observability, runtime clarity, and operator-first design principles.
The deterministic ledger pipeline, shadow verification system, LMDB persistence layer, four observability subsystems (KAGAMI, YAMORI, TATE, KURA), and continuous preview-network validation have all been built through sustained daily engineering — without institutional grants, governance funding, or venture capital.
The treasury model and support path are publicly documented. Support through the TSUNA stake pool helps sustain ongoing development and infrastructure costs.
Infrastructure Status
TSUNAGI is running infrastructure, verified against a live network.
Propagation Artifact Coherence
Merged on main: #68 — Forge promotion now publishes a coherent sealed artifact with verified fragment ancestry. The propagation server rejects incoherent fragment state rather than serving stale ancestry to a relay.
- Sealed promotion publishes coherent fragment ancestry
- Propagation server validates ancestry at serve time
- Stale fragment state is rejected, not served
- Structured truth logs added at publish and serve time
- Regression tests pass, ReleaseSafe build passes
- Relay disconnects traced to stale fragment / sealed mismatch
- Promoted sealed tip’s parent was missing from fragment window
- Relay saw TSUNAGI as stale at connection time (relay_ahead=true)
- Connection dropped after MsgIntersectFound, before MsgRequestNext
Current Live Target
Observing the relay-facing path on preview under live conditions. Artifact coherence was necessary but not sufficient — relay timing still matters.
What Is Proven
Observable, verifiable capabilities — not claims.
Architecture
TSUNAGI is organized as a layered architecture where each subsystem addresses a specific operational concern. The observability stack (KAGAMI, YAMORI, TATE, KURA) monitors and stabilizes the node. The TSURUGI protocol engine manages Ouroboros communication. The deterministic ledger pipeline processes blocks through a modular state machine. LMDB provides persistent storage with transactional guarantees.
Core Pillars
Four foundational capabilities define the TSUNAGI architecture.
Deterministic Ledger
A modular pipeline separating delta extraction, state application, undo management, and persistent storage into independently testable components. No global state. Identical inputs produce identical outputs on every execution.
Shadow Verification
An independent pipeline instance processes identical deltas on every block and compares parity with the primary ledger. Divergence is detected within one block of occurrence. The shadow never influences the primary path.
LMDB Truth Mode
Three-stage persistence with preflight coverage scan, atomic LMDB writes, and automatic memory fallback. Shadow-writes progressively converge the store with live chain state. Operators select the persistence guarantee they require.
Self-Healing Infrastructure
Four observability subsystems — KAGAMI, YAMORI, TATE, KURA — evaluate health, verify integrity, and stabilize artifacts automatically. The node explains its own health rather than requiring external diagnostic inference.
Live Infrastructure
Operational telemetry, decode pipelines, and observability tooling for the TSUNAGI runtime.
Status
Real-time node health dashboard with 20 telemetry fields from the running preview node.
Explorer
Block decode activity viewer with ledger telemetry and decoded event timeline.
Decode
Deterministic decode pipeline visualization showing the block-to-ledger flow.
Operator Guide
Running, monitoring, and maintaining a TSUNAGI node. Operational workflows and readiness status.
Network
Peer connectivity, protocol negotiation, and relay communication diagnostics.
Labs
Experimental tooling, protocol experiments, and research utilities.
Research & Documentation
The architecture, methodology, and vision behind TSUNAGI are documented across four primary documents.
Whitepaper
Complete architecture, verification methodology, security model, and experimental validation.
Manifesto
Engineering philosophy, design principles, and the vision for deterministic infrastructure.
Roadmap
Development phases from deterministic foundation through ecosystem contribution.
Vision
Long-term vision for independent infrastructure and the MUSUBI research direction.
Support TSUNAGI
TSUNAGI is developed independently without institutional funding. Support through TSUNA or the $tsunagi ADA handle helps sustain ongoing development and infrastructure costs.
Funding model and transparency principles are documented on the Treasury page.
TSUNAGI is under active development. Running live on the Cardano preview network. Latest merged milestone: propagation artifact coherence (#68). Current live target: relay progression past MsgIntersectFound under relay_ahead=false conditions. Not a mainnet replacement at this stage.