Cardano Settlement Layer

IOHK selected Serokell to implement an innovative proof-of-stake (PoS) algorithm in order to provide customers with a new reliable financial platform.
Cardano SL is a cryptocurrency made for IOHK, a technology startup that focuses on using peer-to-peer technologies to provide financial services to clients. The goal of the company when they contacted Serokell was to build a peer-reviewed blockchain platform that provides fair and transparent access to financial services. Our team helped IOHK to implement an innovative proof-of-stake (PoS) algorithm in order to provide customers with a reliable financial platform.
Serokell portfolio: Bloskscout project

PoW vs PoS

PoS aims at making the blockchain less power-hungry and more seсure. Unlike preceding attempts of developing a PoS algorithm, Serokell's implementation was based on a proven-secure algorithm Ouroboros.

Some attempts to develop such an algorithm had already been made by other organizations in the cryptocurrency space but Ouroboros came out of the scientific community and its safety was proved mathematically. Serokell’s team helped IOHK to turn it into a functional software system.

Cardano SL project formation

As the foundation for development of a well-protected solution, we used the recently invented algorithm Ouroboros. Pioneer among its class, this PoS protocol motivated our software engineers to realize a practical implementation of the algorithm.

Ouroboros algorithm - a foundation for the development of CardanoSL software solution
Core of Cardano Settlement Layer

Serokell’s team turned a theoretical basis for a new consensus algorithm (Ouroboros) into a working cryptocurrency platform.

The particular achievement of Serokell was the development of the core of the Cardano Settlement Layer. It works as the basement layer for all other components of the Cardano platform and the main place where the creation of the new crypto blocks takes place.

Any technical issues that appeared due to internals of this new consensus algorithm were resolved by Serokell in collaboration with researchers from IOHK, the University of Connecticut, the University of Athens, the University of Edinburgh, Aarhus University, and Tokyo Institute of Technology.

Researchers' collaboration
Our cooperation created a beautifully engineered Haskell project at the intersection of blockchain, mechanism design, and cryptography.
CardanoSL: the intersection of blockchain, mechanism design, and cryptographyCardanoSL: the intersection of blockchain, mechanism design, and cryptography
Ouroboros algorithmSerokell portfolio: CardanoSerokell Solutions: Cardano SLSerokell use cases: CardanoSL

Particular features we implemented:

Serokell cases: Cardano financial platform
Serokell portfolio: Cardano blockchainSerokell cases for IOHKSerokell portfolio: Cardano SL audit IOHK financial platform: Cardano SLIOHK solution: Cardano SLSerokell  project: Cardano SLSerokell software project: CardanoSLSerokell software development case: Cardano
  • blockchain based on a new PoS consensus algorithm;
  • ledger that allowed safe transactioning of users’ funds;
  • embedded scripting language support;
  • network implementation, CLI client for Cardano network;
  • web backend for cryptocurrency’s wallet Daedalus;
  • a block explorer for Cardano network (in collaboration with IOHK engineers);
  • web app for delivering the ADA tokens sold during ICO;
  • launch of cryptocurrency in a federated setup (7-node cluster) with a distribution of tokens from ICO.
fintech development case: Cardano SLSerokell portfolio: Cardano

Notable Dates

May 2016
Start of development for app distributing tokens to ICO participants
September 2016
Ouroboros consensus release
October 2016
Serokell started development of CSL
January 2017
V 0.1 testnet is released
Feb - Jul
February - July 2017
Testnets v0.2 to v0.5 released
September 2017
Launch of Cardano SL
October 2017 - February 2018
Maintenance of CSL mainnet, improving node's performance and reliability
March 2018
End of Serokell's contract with IOHK
Serokell use cases: CardanoSLSerokell portfolio: Cardano


As a result, CSL has become the first implemented part of the Cardano cryptocurrency platform.
Cardano SL project: results

Cardano has become one of the safest and most scalable cryptocurrency platforms on the market. All that is due to Ouroboros that uses mathematical proof of safety based on the stability of the transaction log.

At the moment of launch (2018), the platform was recognized #7 in the top of 100 cryptocurrencies by market capitalization. At the time of working on the project, Cardano market capitalization reached $311 308 025 with $1.09 per ADA (Cardano’s cryptocurrency).

Right now, PoS algorithm first implemented by Serokell and IOHK is being used by several blockchain companies.

At the time of working on the project, Cardano market capitalization reached $311 308 025 with $1.09 per ADA (Cardano’s cryptocurrency).

At the time of working on the project, Cardano market capitalization reached $311 308 025 with $1.09 per ADA (Cardano’s cryptocurrency).

Serokell case study: Cardano Settlement Layer

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