Published in


Decentralized Oracles: New Training Bounties — SGX & more. Learn and Earn RLC!

A few weeks ago, we launched a series of developer training bounties for decentralized oracles. Developers contributed to the four Gitcoin issues funded by iExec. Three of them already claimed their bounties, by successfully completing the training and delivering the application. So congratulations to @erazhu33, @j48 and @pengiundev!

💡 Want to learn more about iExec? Check out iExec Academy!

iExec Academy aggregates all content related to the project. You’ll find articles, tech documentation, videos, interactive demos, and much more! Whether you are a beginner or an expert, a developer or crypto-enthusiast, you’ll find what you are looking for on iExec Academy!


If you like the sound of earning RLC while learning how to develop off-chain computing for Ethereum, then you will be interested in the following announcements (more chances to be rewarded in RLC tokens):

  1. Four winners have been selected for their contributions to the oracle project Idea Box
  2. These winning project ideas will be published as four new Gitcoin training bounties for devs to deliver and be rewarded in RLC tokens.
  3. A new training bounty will be published offering a reward for anyone who provides an upgrade to an existing oracle with either Intel SGX (hardware enclave) implementation or a Frontend.

1- Four winning ideas from the idea box

We’ve received a lot of cool oracle ideas that can be built on top of iExec. Here is the winning selection made by the team:

1. Bank Card Payment Validator: [$100 in RLC for being #1]

  • Data source: a bank card payment processor (ex: Dwolla)
  • Input: a payment ID
  • Output: payment amount & payer ID

2. Ethereum Weather Station: [$20 in RLC]

  • Data source: OpenWeatherMap
  • Input: date + location
  • Output: simple weather description to determine. Ex: [sunny|cloudy|rainy|storm]

3. Ultimate Package Tracker: [$20 in RLC]

  • Data source: a tracking service (ex: UPS, La Poste)
  • Input: tracking ID
  • Output: simple delivery status

4. Ethereum Anemometer: [$20 in RLC]

  • Data source: Wind data provider (ex:
  • Input: Longitude & Latitude
  • Output: simple environmental condition including wind strength

🎉Congratulations to Mohammad, Allintether, Sergey and Callum, expect an email from us very soon! There will be another batch of winners, so it’s not too late to submit your oracle idea using this form for the chance to get rewarded with RLC tokens.

2- Four new decentralized oracles to build

Based on the four winning ideas, we’ve opened four new Gitcoin bounties that are now waiting for a developer to work on:

  1. Bank Card Payment Validator: [$100 in RLC] (Apply on Gitcoin)
  2. Ethereum Weather Station: [$100 in RLC] (Apply on Gitcoin)
  3. Ultimate Package Tracker: [$100 in RLC] (Apply on Gitcoin)
  4. Ethereum Anemometer: [$100 in RLC] (Apply on Gitcoin)

Also, note that the TLS Notary DOracle bounty is still open (Gitcoin / Github). The RLC reward is still up for grabs for anyone willing to tackle it!

3- Can you provide Intel SGX TEE Implementation or a Frontend?

If you have followed all the steps detailed in this article then you should have all the skills needed to get your own oracle up and running. You now know how to connect a smart contract to an API, and let’s make it clear: this is a game-changer for any Ethereum developer looking to build a next-generation DApp, an application having real-world traction.

And yet, depending on your use case, you might well need a frontend to interact with your users. Let’s consider a sports betting platform on Ethereum: Once a game is finished, the winner of the bet should be able to click on some button to ask for an oracle update, so that it will go fetch the trusted game result from the API, and finally trigger the payment. Right?

Also, depending on what’s at stake in your betting DApp, you might consider adding another layer of security to the oracle execution, and choose to run the oracle off-chain logic (API call) in a trusted enclave (read more regarding SGX support on iExec workers).

That’s why we will offer a bounty to anyone interested in “upgrading” an existing oracle with either:

  1. Intel SGX Compatibility (Trusted Execution Enclave technology) [$100 in RLC] (Open an issue here following this template)

2. A Frontend user interface (the user-facing part of the app running in the web browser) [$100 in RLC] (Open an issue here following this template)

Get Started!

Sounds exciting? Then let’s get started! Join our #tech-support slack channel.

If you‘d like to run your oracle in a trusted enclave, read the TEE related documentation here.

Otherwise, if you want to trigger an oracle update from a JS frontend, then go read the iExec SDK library documentation here.

Once you get your code ready in a Github Pull Request, we’ll create a Gitcoin bounty to proceed with the reward of $100 in RLC per upgrade.

Off-chain computing and oracles is a complex topic made easy with iExec. Go spread the word!

Interested in following the iExec project? What’s next?
Before iExec V4 (the high-performance computing version with GPU support) is released this year, we’ll be giving more news on the recent developments of each of the recent announcements. To be the first to know and get exclusive updates, subscribe to the iExec newsletter and follow on social media.

The iExec team is reachable on Slack, Gitter or Telegram. You can subscribe to our newsletter to be the first to know about announcements news and community events.

WebsiteSlackTelegramTwitterYoutubeGithubTechnical Documentation



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Julien Béranger

Julien Béranger

CEO and co-founder of Āto | Founder of Strat | Volonteer at Emmaüs Connect | Contrib at Concord