Today we launch the second Cardano testnet, which is for the IELE virtual machine (VM) and follows our recent launch of the KEVM testnet. The technology is not only an important step on the Cardano roadmap, but also for the industry – in offering robust and reliable financial infrastructure. Developers now have the opportunity to explore the smart contracts technology that will be offered as part of Cardano, and to give us their feedback, which we look forward to receiving over the coming months.

Why smart contracts?

In many business processes that involve the exchange of value (including money, property or shares) intermediaries are involved in checking that the terms of the agreements are complete and unambiguous as well as satisfied before the exchange can take place. These intermediaries add to the cost of a transaction. The technology of smart contracts (also known as self-executing contracts or blockchain contracts) has emerged as a way of addressing the need for this verification by reducing the time, third-party involvement, and cost of reliably executing an agreement.

Smart contracts are software programs that are immutably stored on the blockchain. They are executed by virtual machines and store their data in that same immutable infrastructure. Smart contracts offer great benefits to businesses looking to optimize their operations. Many industries – including automotive, supply chain, real estate and healthcare – are investing in research to understand how this technology can make them more competitive.

What smart contracts technology is currently available?

There are a few players on the market that offer smart contract capabilities including Hyperledger, NEO and Ethereum. The technology is evolving to meet the market’s demand for platforms that are fast, secure, accurate and can be trusted. Many businesses have tried to deploy broad-scale applications on these platforms and have run into problems (DAO hack, Parity bug and POWH coin to name a few) with these evolving platforms. Despite widespread publicity the most serious bugs continue to reappear in smart contracts. There is a lot of room for innovation here and IOHK is working hard to become a leader in this technology.

What Is IELE?

IELE (pronounced YELL-eh) is a virtual machine, with an attendant low-level language, designed to execute smart contracts on the Cardano blockchain. It has been developed by Runtime Verification in partnership with IOHK, which provided funding for the project. The word IELE refers to nymphs in Romanian mythology.

How does IELE improve on smart contracts platforms?

IELE is designed to meet the evolving needs of the market for smart contracts by:

• Serving as a uniform, lower-level platform for translating and executing smart contracts from higher-level languages. It supports compilation from Solidity and many more languages are set to come.

• Providing a uniform gas model, across all languages.

• Making it easier to write secure smart contracts. IELE is 'correct by construction' so many errors discovered after the fact (during code execution) in other VMs are not possible in IELE.

• Using a register-based as opposed to stack-based architecture.

What can I do with IELE that I could not do before?

IELE contains two parts: a correct-by-construction VM designed using the K framework, and a correct by construction, Solidity-to-IELE compiler, also designed using the K framework. When you write your Solidity program and try to compile it using the Solidity-to-IELE compiler, it will catch many of the errors that previously would have been missed and that have caused many smart contracts to fail or be exploited.

In addition, as IELE development progresses, we plan to deliver 'surface languages' allowing programmers proficient in Javascript, Python and other languages to have an easy way to integrate smart contracts into their applications.

What do I do next?

The IELE language and its VM are completed. It is now in the process of being integrated into Cardano, which will provide a blockchain to store and retrieve data. While the integration is taking place, developers have the opportunity to use the IELE VM along with the Mallet and Remix tools to create and execute smart contracts on the IOHK testnet site.

You can also start getting a feel for the capabilities of both IELE and its VM – and even learn to write IELE code directly!

Join the conversation!

Related video updates

Artwork,

Mike Beeple

The first Cardano smart contracts testnet launches today, the KEVM testnet, a correct by construction version of the Ethereum Virtual Machine (EVM) specified in the K framework. This technology, produced by Runtime Verification with the support of IOHK, is the first time that a complete formal semantics of the EVM have been produced. This is an important first in cryptocurrency that is a necessary step towards the promise of third-generation blockchains. A smart contract allows you to exchange something of value - money, property, shares - by means of a software protocol. The terms of exchange are agreed upon by the parties involved in the same way as a traditional contract, and the contract is executed automatically on the blockchain.

Developers will be able to take any application that runs on the EVM and execute it on the KEVM, which can also be used to rigorously prove that smart contracts work correctly. This is done by formally specifying a contract's desired properties in K, combining the contract with the KEVM specification, and then using the K framework to verify those properties.

Our second Cardano testnet to launch will be IELE, which is a new virtual machine for Cardano. IELE will be launched in July and is a register-based virtual machine similar to LLVM with an unbounded number of registers, that supports unbounded integers. With IELE, developers can write, compile and execute smart contracts, with improved security and performance compared to the KEVM testnet.

For now, we recommend that developers use the Solidity language on both testnets. However, the vision is that eventually smart contracts will be written in high-level languages that translate to IELE, such as new languages like Plutus (being developed by IOHK), but also existing languages such as Java or Python, and then IELE-to-IELE translators ensure the resulting code is optimal.

Cardano Testnets Website

K was developed by Runtime Verification in collaboration with Professor Grigore Rosu's Formal Systems Laboratory at the University of Illinois at Urbana-Champaign during the past 15 years, and incorporates the state of the art in language design, semantics and formal methods. Read more about the K framework in this blog from Prof Rosu, founder of Runtime Verification. A blog about formal verification and what this means for smart contracts will follow soon.

Smart contracts must be formally verified, so they run exactly as specified and are free from bugs or flaws. Only then can they be widely adopted as financial infrastructure that can be relied upon by billions of people.

We look forward to receiving your valuable feedback about using the testnets which will help us make Cardano best in class.