Blockchain Commons has, over time, released a number of reference apps to demonstrate the usage of its design principles and specifications. They may also be combined into an ecosystem that demonstrates the Gordian Marco-Architecture and its theory of functional partition when applied to the Bitcoin ecosystem:
In this example, the Gordian Reference Apps are all linked by airgaps and torgaps, to demonstrate how privacy and security can be maximized while still maintaining a very usable ecosystem. However, transport specifics become less important when using the Gordian Marco-architecture as a whole, and so in a real-life ecosystem, apps may be normally Networked.
Note that some of these apps are deprecated: they still serve their purpose as references for specific architectural roles, but are not updated and supported. The most updated apps are listed on the Apps page
See Gordian Architecture Roles for definitions of roles that apps can taken within this architecture.
Networked Services
Internet services can be fully networked if they are correctly partitioned:
Fully Noded Server
**Roles: Cosigner, Network Server, Seed Generator, Seed Vault (partial)
Fonta1n3’s Fully Noded Server demonstrates how to separate the functionality of a Bitcoin server (which transmits transactions to the Bitcoin network) from its connected Fully Noded Wallet (which holds secrets and generates transaction). It’s available as a Bitcoin server for MacOS machines. (This grew out of Fonta1n3’s work on the Gordian Server, which we’ve deprecated because his work on Fully Noded is more up-to-date.)
Airgapped Apps
Closely held devices allow users to protect their confidential data with Airgaps. Gordian Seed Tool is our prime Reference App for demonstrating this functionality, while LetheKit offers another style of secure seed generation:
Gordian Seed Tool
Roles: Cosigner, Seed Generator, Seed Vault
A cryptographic seed manager for your iOS device. Allows the maintenance of seeds in a closely held device and the easy use of those seeds through Envelope Requests for either specific keys or for the signature of PSBTs. This is our most developed app, and the one that best displays a variety of ways to achieve the Gordian Principles.
LetheKit
Roles: Seed Generator
A do-it-yourself hardware kit that can be used to generate secure seeds for Bitcoin. It shares functionality with Seed Tool, but functions as fully airgapped hardware rather than software on a closely held but potentially connected device. It’s also more tightly partitioned, focusing exclusively on seed generation.
Gordian Cosigner. (DEPRECATED)
Roles: Cosigner, Seed Vault
An offline PSBT and multi-sig signer. You can import keys and read PSBTs via QR code. After you sign the PSBT, you can then transfer it back to your Wallet across an airgap, which will coordinate the broadcast of the transaction. The current iteration supports Seed Generation, but the plan was to remove it to better partition the services. This app has never advanced to a full release, in large part because its functionality, and thus its reference examples, have been superceded by Seed Tool.
Gordian QRTool (DEPRECATED)
Roles: Seed Vault
A more general data storage tool that displays how the Gordian Principles can apply to the protection of a variety of digital data that has been encoded as QRs. It also shows the tightest partitioning, allowing secure seed (or other data) storage and nothing else.
Gordian Wallet (DEPRECATED)
Roles: Cosigner, Policy Coordinator, Seed Vault (partial), Transaction Coordinator
Gordian Wallet is a mobile Bitcoin wallet that supports sophisticated #SmartCustody features such as multi-sigs and PSBTs. It acts as: a policy coordinator, determining how you set up your accounts; a transaction coordinator, creating transactions based on your policies; and a broadcast coordinator, determining how to send our your transactions. Note that the Seed role of Gordian Wallet is limited because its multisig design shares Seeds with the linked Gordian Server.
Microservices
Blockchain Commons microservices demonstrate how services can be built for very specific functionality within the Gordian Architecture.
SpotBit
Roles: Pricing Calculator
A price-info microservice, used by Gordian Wallet (and potentially other paritioned services) through a torgap. Spotbit can be used to aggregate Bitcoin pricing information from a variety of exchanges and to store that data.