Unledger Protocol

A Small experiment using ChatGPT to build a simple Ledger inspired from the UTXO Model. My goal is to get more familiar with the concepts and for that I like to build random stuff to learn.

• Supports multi assets and contracts
• 100% in typescript
• Built using Postgres DB
• 2 External dependencies: Kafka, Postgres
• Multiple tests
• Built with Deno 2
• Exponential backoff mechanism to retry processing requests when selected UTXO is already spent. (Intent based)
• Distributed architecture using Kafka.
• 4 postgres tables: utxos, transactions, contracts and policies.
• Burn Assets or make them immutable (configurable in the policies table)
• Contracts to lock/unlock assets.
• Custom logger
• TBD: Added Direct Listing with partial and all-or-nothing examples
  • No support for fractional amount. (Future Improvements: Automatically resolve the fractional amount and dispatch the amount correctly. It is required to automate an order book and select matching orders, it is far from complete or functional in the current state.)
• TBD: Implement ED25519 Signatures and transaction validity (started)
• TBD: Implement NFT/FT/Multi Assets (started)
• TBD: Websocket, HTTPS, and Protobuf ? Supports
• TBD: User Vault

Transactions

The transaction flow is built with a 'I want to send X coins to Y wallet' instead of an offline deterministic approach. Meaning that the user does not have to build a transaction, only send its intent. For a simple exchange it has to know the recipient id and the assets to send and for a contract it has to know the contract ID and the required inputs to unlock the output. Then the system tries to achieve the request, if it was public and decentralize. This approach would lead to a lot of spam onto the network because it tries few times to process the request.

Usage

1. Install deno.
2. Run containers

docker compose up -d

2.1. Run SQL ledger.sql

3. Enjoy.

deno run -A __tests__/clean.ts
deno run -A __tests__/setup.ts
deno run -A __tests__/policy.ts

Start at least two consumers to get faster processing

deno run -A __tests__/consumer.test.ts
deno run -A __tests__/consumer.test.ts

deno run -A __tests__/producer.test.ts

To burn tokens

deno run -A __tests__/burn.test.ts

Contracts

deno run -A __tests__/contract.test.ts
# Direct listing and attempt to build the fondation for an order book (partial filling of smart contract, using a ratio)
deno run -A __tests__/direct_listing.ts
deno run -A __tests__/partial_direct_listing.ts

As of 2025-04-13:

• Need to finish contract (all-or-nothing and partial filling)
• Need to add signatures
• Then evaluate time to implement in lucid adventure (for the in-game marketplace and assets tracking)
• Add NFT (Currently only FT are implemented)