Milen Radkov
Feb 21 · 3 min read

Hey guys,

Yesterday we had our 7th Blockchain Developers Meetup this time dedicated to Aeternity’s Sophia smart contract language.

Blockchain Developers Meetup 0x07 Aeternity Sophia workshop

For those of you who couldn’t attend or miss it — here is a brief summary of what we discussed and what we covered, also all of the resources.

Blockchain developers digest

As usual we’ve started our meetup with an overview of the blockchain ecosystem from the developers perspective.

Hristo’s blockchain developers digest

Hristo walked us trought the recent blockchain developers news digest, and explained some of the most important ones:

  • Ethereum Hard Fork — Constantinople and Petersburg
  • Aeternity Minerva Protocol Update Release
  • Bitcoin BIP174 — Partially Signed Bitcoin Transaction (PSBT)
  • LeapDAO MVP /More Viable Plasma/
  • Monoplasma
  • Baidu Blockchain Engine (BBE) Platform
  • WeiDex Developments

After the blockchain developers news digest, it was time to step into Sophia ML.

Sophia ML presentation

Milen covered the specifications of the language, showing a simple smart contract, and talking about the different types and built-in functions we have in Sophia.

Sophia types and Built-in functions
Solidity vs Sophia smart contract comparison

He talked about what improvemets can we expect to be introduced with the following Minerva update — such as safe arithmetical operations and more.


For the workshop part, Milen had prepared an Auction smart contract both in Solidity and in Sophia and walked us through every single detail, explaining and comparing the two of them.

Milen showing the differences between Solidity and Sophia

The auction had functions for placing a bid, refunding losing bids, withdrawing the winning bid by the owner of the auction and a function to cancel the auction.

Sophia Auction aepp — partial code

Milen covered the syntax specifics of the Sophia Language. Function definitions and how can we create ourselves helper functions to use as modifiers and more.

The whole code you can get from the github repo provided below in the resources.


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Milen Radkov

Written by

Founder & CEO @ - DLT & Blockchain Solutions ( | Software Engineer | Blockchain Expert and Developer | Entrepreneur



hack - DLT & Blockchain Solutions

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