In this article we look at type of economic attack on DeFi projects in the form of manipulation of price oracles.

On Ethereum, where everything is a smart contract, so too are price oracles. As such, it’s more useful to distinguish between how the price oracle gets its price information…

A few months ago Extropy published a survey on Ethereum staking solutions, in this article we introduce staking on a new PoS blockchain, Mina.

Mina is known for being the world’s lightest blockchain! Individuals or businesses can contribute to network security by becoming nodes or block producers. They can contribute…

In light of the recent $611 million exploit of PolyNetwork we present a short overview of smart contract auditing and explain our audit process. Extropy is working on tools to give more insight into exploits based on tokenomics, how these can be detected and avoided. …

Following our previous post, Coding a DeFi Arbitrage Bot, many readers report an issue preventing the arbitrages executed by our bot from completing successfully. As it turns out, this issue is caused by frontrunners, executing the trades before our trading bot itself, so that the order on the 0x exchange…

Run faster with security

Openzeppelin is mainly known in the Ethereum community for its set of utility smart contracts, that are used on a daily basis by Solidity engineers who want to develop faster with security (DevSec).

Openzeppelin Defender was born out of the idea to streamline the connection between…

Successful audit

Our process:

Float’s article:

Audit report:

We recently provided a security audit for Float Protocol and received positive feedback from the team. Here’s a quick overview of their positive response:

  • Full trust in our team of developers
  • We have a wealth of experience working with early-stage teams
  • We go above and beyond the norm
  • We work with our clients iteratively

Extropy have been auditing smart contracts since 2017 and advising clients on the best security practices.

If you would like to know more about our process please get in touch. are a consultancy for blockchain and cryptography based in Oxford, UK.

We help businesses and startups realise the full potential of blockchain and bring cutting edge technology to all our clients.






Ethereum 2.0 staking is the latest and hottest way to earn passive income as a node validator, it boasts high and predictable-ish returns that are attracting many investors and allowing to earn secondary products such as erc20 tokens or collateral loans in order to stay liquid while the funds are…

In the first part of this series we explained what arbitrage means in the context of decentralized finance and our chosen bot strategy for spotting profitable opportunities between decentralized exchanges.

In this second and final article we will conclude the arbitrage bot tutorial by diving in the code step by…

In our previous article, we introduced Decentralized Finance as a whole, casting light upon the basic building blocks of this new ecosystem and the main strategies used to earn passive income, mainly “yield farming” and “arbitrage”.

In this article we are going to guide the readers through a step by…


Oxford-based blockchain and zero knowledge consultancy and auditing firm

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