Self-hosted pricefeed for wallets

[IMPACT]

Currently, wallets that want to provide price feed for tokens in Cardano have to rely on centralized APIs provided by DEXs. This is not in the spirit of blockchain where we want to encourage projects to self-host solutions instead of relying on centralized APIs. Additionally, the current situation is also a risk for these projects because it's entirely possible for the price of an asset of one dApp to differ greatly from the price on another dApp.

We plan to provide an Oura source+sink for projects to be able to self-host their own price feed node for Cardano assets to provide greater resilience and more decentralization. We plan to integrate at least 2 DEXs (stretch goal 3 DEXs) as part of this proposal

Having access to self-hosted price feeds will not only boost decentralization, but also enable this kind of price data to be easily fed to oracles and indexer protocols built on top of Cardano or sidechains/layer 2 protocols such as Milkomeda. Price feed oracles are one of the core DeFi primitives so we expect this project to also unlock new kinds of dApps on Cardano

DEXs in Cardano are still relatively new. That means there are two risks:

1. We may integrate a DEX that is popular today, but the DEX eventually loses to a new competitor
2. The DEX may update to change how they work which means we have update our indexers to match their update.

We hope that after the initial implementation of this proposals, enough projects build on-top of this proposal that DEXs and other projects help us maintain this software.

That being said, we will do our best to maintain the code after we finish this proposal (as we intend to use the result of this proposal ourselves at dcSpark)

[FEASIBILITY]

Q2: Investigation into which DEXs we should pick based on usage patterns at the time and how easy it is to consume their on-chain data

Q2~Q3: Implement the Oura source+sink for 2 DEXs (stretch goal: 3 DEXs)

• $40K - Developer cost of the investigation + implementation
• $5K - Devops & hosting costs associated with easy deployment of these price feeds

The dcSpark tooling team has experience with Oura and our company also has experience with writing / reading Cardano dApps as well.

[AUDITABILITY]

Progress will be measured by our ability to integrate DEXs into the price feed system

Success looks like

• Many projects self-hosting the price feed instead of relying on centralized price feeds
• Projects using these price feeds to power oracles and indexers

New proposal