Keep it Confidential: Build the First Ever Confidential DApp in Solidity, and Win

Oasis Network
Oasis Foundation


Join the Keep it Confidential Hackathon to build on Sapphire, the first ever Confidential DApp in Solidity, and win prizes.

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We recently launched the Sapphire ParaTime — an industry-first Confidential EVM runtime — onto Testnet. Now, we want to offer developers the chance to experience Web3-enabled confidentiality in a language they already know and understand.

We are excited to launch our Keep it Confidential Hackathon, giving you the chance to build the world’s first confidential DApp in Solidity.

Sapphire is a groundbreaking developer environment as it is the first and only confidential Ethereum Virtual Machine (EVM) compatible ParaTime. This runtime has the ability to help scale blockchain rapidly towards Web3 and allow EVM developers to quickly lay the foundations for privacy-enabled blockchain DApps, which are becoming a necessity as users demand data sovereignty.

Sapphire offers Solidity developers a familiar, Ethereum-compatible building environment, but with the added benefits of Oasis’ privacy technology which is key to allowing blockchain to be part of the Web3 world.

Important Info

Submission Period: September 14, 2022 (00:00 am UTC) — October 21, 2022 (11:59pm UTC)

Judging Period: October 21, 2022 (10:00 am UTC) — October 28, 2022 (11:59pm UTC)

Winners Announced: On or around October 31, 2022


  • 1st place prize — $5000 (equivalent in ROSE)
  • 2nd place prize — $2500 (equivalent in ROSE)
  • 3rd place prize — $1500 (equivalent in ROSE)

We are looking for innovative front-running resistant and privacy-first applications built on Sapphire.

A familiar EVM environment with added confidentiality and privacy-preserving technology opens up a new world of opportunities for builders.

Some ideas we would like to see in the Hackathon include, but are not limited to:

Applications with Sensitive Data:

  • Sapphire lets you bring sensitive data, like health, financial, and personally identifiable info on chain safely.

Confidential DeFi:

  • MEV-proof DEX, private or undercollateralized lending.


  • Many popular Web2 games we know and love have private state or game logic. Sapphire enables bringing more on chain.

Confidential NFTs:

  • Data-backed NFTs with associated private information to bring NFT utility to the next level.

DID — Decentralized identity:

  • With DID DApps can verify and whitelist users. Sapphire can be a game changer as DApps can now be built with these benefits without risking users’ privacy.

Decentralized Society and Soulbound tokens:

  • Maintaining sensitive information linked with external-facing data has always been challenging for DApps. But with Sapphire, you can build and create privacy-preserving data-backed tokens or Soulbound tokens, a critical pillar for decentralized society.

Submission Requirements

  • Provide a short summary of your project, including a description of what it is and how you want to evolve it.
  • Provide a link to your code repository for judging and testing. Code must be open sourced.
  • Provide smart contract deployment links (
  • Include a video (less than 5 minutes) that shows how your project works and why you built it. Videos must be uploaded to YouTube, Vimeo or a similar site and made public.


Judging Criteria

  • Implementation Quality: Does the project demonstrate high-quality development?
  • Potential Impact: How large an impact could the project have? How many users could the project potentially attract?
  • Innovation: How creative and unique is the project?
  • User Experience: Does the project’s design make the user experience easy?
  • Originality: The project must be substantially different from any other app submitted by the same submitter/team/organization and must be the original work of the submitter, be solely owned by the submitter, and not violate the IP rights of any other person or entity
  • Confidentiality: How well does the DApp utilize confidentiality?

Support and relevant documents

To support the hackers during this Hackathon, we have a dedicated channel #hackathons on our Discord. Feel free to ask questions there.

Getting started guide & documentation:

Upcoming Events:

  • Sapphire Making Debut on September 22nd — Watch Replay
  • Hashlips AMA on September 22nd — Listen to the Replay
  • DeveloperDAO AMA on September 27th — Listen to the Replay
  • r/cryptocurrencies AMA on September 28th
  • Office Hours on September 28th — Register Now
  • Bitcoin Talk AMA on October 4th
  • Twitter Space about how important Sapphire is and its impact on Web3 — Privacy for NFTs with Metamirror on October 6th

Good Luck!



Oasis Network
Oasis Foundation

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