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Serokell company is mentioned among the top developers 2020.

Serokell Gets Listed As Top App Developer

We already have a small tradition to announce the mentions of Serokell among the top developers. Today, we got listed on one more independent software development platform – [TopAppDevelopers.com](https://topappdevelopmentcompanies.com/ee/directory/app-developers/estonia). 

Our success would not be possible without our loyal customers. We would like to thank all of you for supporting our work with your valuable feedback and reviews.

Serokell Among Top App Developers

Read about the participation of our logician Danya Rogozin at LCFS 2020 and the thesis about which he gave his talk there.

##

On the 7th of January, Danya Rogozin participated in the conference Logical Foundation of Computer Science, Miami, Deerfield Beach. [LFCS](https://lfcs.ws.gc.cuny.edu/lfcs-2020/) is a logical and computer science conference, topics of which cover such areas as constructive mathematics, type theory, proof theory, foundations of mathematics, etc. 

![logical foundations of computer science](/files/0f/0f2k6r53.logo_general2.png " ")

Danya gave a talk on the results that he obtained in his thesis two years ago. The title is Modal Type Theory Based on the Intuitionistic Modal Logic ${\bf IEL}^{-}$. This logic [was introduced by Sergei Artemov and Tudor Protopopescu](https://arxiv.org/abs/1406.1582) to solve some issues related to constructive aspects of agent knowledge and belief.

## Considering modal logic from a computational perspective

This logic was considered from a computational perspective. It's a quite curious coincidence that axioms of this logic are pretty similar to the types of methods `pure` and `(<*>)` in the Applicative class well-known in Haskell. In this work, he considered the modal typed lambda calculus that is Curry-Howard isomorphic to the logic  ${\bf IEL}^{-}$ and shown such metatheoretical properties as subject reduction, strong normalisation, and confluence.

To get a closer look, you may check out [the proceedings book](https://www.springer.com/gp/book/9783030367541), where the articles based on the speakers' talks are fully presented.

Also, if you want to read some of Danya's introductory work about modal logic, feel free to head to his [excellent post series](https://serokell.io/blog/incomplete-and-utter-introduction-to-modal-logic) on our blog. In it, he covers the basics of modal logic and explores its connections to fields such as computer science, topology, and foundations of mathematics.

Serokell at LCFS 2020

We Are Hiring a Haskell Software Engineer

We're hiring Haskell developers for our new remote workspace project!

Become a part of an international, fully remote community! Serokell has started with Haskell and now provides services in scientific research and engineering fields using functional programming languages. We’re seeking Haskell developers to work on our new remote workspace project, [Ment](https://ment.hr/).

While working on the project your primary responsibility will be to develop integrations with external services/applications like JIRA and Telegram. You will maintain a zoo of microservice daemons for reliable synchronization of data from external services to our application. There will be a great deal of writing Haskell and even more of architectural decision making to ensure data synchronization is performed optimally.
 
## Requirements

More or less required:
* Solid knowledge of Haskell 98 features: typeclasses, аpplicative functors, monad transformers.
* Familiarity with the modern Haskell ecosystem. You should be able to use `text`, `mtl`, basic lenses, Stack/Cabal, type families, template haskell (use existing TH generators, not write your own), `QuickCheck`/`Hedgehog`. (If one of these items is missing, it's not critical).
* Knowledge of the fundamental algorithms and data structures like binary search tree, DFS, hashtable, quicksort, etc.
* Knowledge of computer networks: HTTP,  understanding of poll- and push- based data synchronization models and their usage in modern service APIs.
* Good coding culture (code structuring and decoupling, patch management with git, code review practices).
* Good level of self-organization.

Good-to-have, but not crucial:
* Cryptography: very basic knowledge, public/private keys, signing, encryption, hashing.
* Parsers: writing own parsers, using parser combinators and/or parser generators.
* Haskell: experience with popular libraries for real-world problems (web servers, streaming like `conduit`, serialization, databases,etc.).
* Haskell: advanced type-level features: `GADTs`, `DataKinds`.


## About us

Serokell is fully remote — our diverse background and fast-moving environment make everyday communication and workflow creative and fun. Our international team consists of talent from various spheres: software engineers, computer scientists, mathematicians, and many more inventive individuals.

We work flexible hours in small, friendly teams and abide by certain principles: as little bureaucracy as possible (no unnecessary meetings, super detailed reports, etc.), proper management, healthy work/life balance, and continuous improvement.

<hr>

If you’re interested, contact us via email: jobs@serokell.io.

Serokell Takes First Place at TON Contest

Our team beat the competition at TON smart contracts contest with top-notch computer science skills, hard work, and Haskell. Read this post for more details.

On November 15, 2019, Telegram announced the winning submissions for their [TON smart contract contest](https://t.me/contest/103). In the contest, participants were asked to create at least one of the smart contracts from a list of five contracts that was provided.

The first place and $28,750 was taken by [this submission](https://contest.com/blockchain/entry404). If you have been following our blog, it might look familiar.

## Serokell takes the largest prize at TON smart contracts contest 

Our team of five of the Serokell’s finest submitted two smart contracts for Telegram Open Network:

1. [Asynchronous payment channel](https://github.com/serokell/ton-paychan) in FunC with a CLI in Fift. Asynchronous payment channel enables participants to send payments to each other off-chain while still guaranteeing the final settlement.  
2. [Multisignature wallet](https://github.com/serokell/fift-asm-dsl) with TVM assembler embedded in Haskell. Multisignature wallet enables the funds on an address to be accessed only if multiple signatures by multiple private keys are provided.

You can read more about the technical details of the solutions in [this blog post](https://serokell.io/blog/ton-blockchain-competition) by one of the participants, our CTO Kirill Elagin. 


## Hard work pays off 

The participants from Serokell’s side were: our CTO, one of our team-leads, and three experienced blockchain developers well-versed with Haskell and other functional programming languages. 

![Our team for the TON contest. Everybody did amazing, thanks!](/files/4k/4kjy381m.participants3.jpg)

All in all, we tracked 380 hours on this project including meetings, getting to know documentation, and development. 


##  Hackathon that breeds innovation

There were a lot of [impressive submissions](https://contest.com/blockchain) from other teams as well. TON is one of the more promising projects in the blockchain space, and it is wonderful to see many great minds working on it already. 

At the end, we would like to thank Telegram for the experience. In the words of Kirill: 

> This spirit of a hackathon, close teamwork, the need to quickly dive into a new technology – I think all engineers know how exciting it is.

Viktor Kazanski

Denis Oleynikov

Pavel Golovin

Mika Logan

Constantine Ter-Matevosian

Alexey Danilevsky

Vladimir Serov

Nikolay Yakimov

Inna Logunova

Ivan Smetannikov

Aleksandr Pak

Leonid Vasilev

Ilya Lubimov

Andrey Borzenkov

Markus Barenhoff

Kirill Kizilov

Kristina Martin

Nurlan Alkuatov

Jay Zelenskyi

Adrián Enríquez

Anton Sorokin

Uliana Sushinskaia

Vadym Salnyk

Daniel Kazantsev

Vito Canadi

Chris Höppner

Lars Jellema

Yorick van Pelt

Yegor Timoshenko

George Agapov

Kirill Andreev

Brian Kean

Val Baturin

Kyrill Briantsev

John Burnham

Ivan Dolgakov

Kirill Elagin

Pavel Gliev

Joakim Goldkuhl

Ivan Gromakovsky

Kostya Ivanov

Murat Kasimov

Alexander Rukin

Vasiliy Kevroletin

Mikhail Kilianovski

Maxim Koltsov

Dmitry Kovanikov

Artem Kuznetsov

Nikita Lisitsa

Allan Lukwago

Dmitry Mukhutdinov

Alexander Nikolaev

Dmitry Nikulin

Konstantin Andriotis

Artem Ohanjanyan

Ilya Peresadin

Pasquale Pinto

Danya Rogozin

Rinat Stryungis

Alexander Tiunov

Paul Tsupikoff

Mitchell Vitez

Josef Vlach

Mikhail Volkhov

Murad Murzaev

Vladislav Zavialov

Arseniy Seroka

Jons Mostovojs

Felix Stegerman

Roman Melnikov

Jaroslav Shadrin

Marina Sharygina

Leonid Cupikov

Ping Chen

Sergey Litovchenko

Nadir Asanbekov

Dmitry Lifanov

test1

Domagoj Cerjan

Ellina Poponnikova

Dmitrii Susloparov

Damir Garifullin

Aleksandr Pakulev

Kirill Kuvshinov

Roman Alterman

Anton Dobrenkiy

Alexandra Voicehovska

Eduard Sachava

Sandeep Chandrika

Grigory Pevnev

Artem Velychko

Olga Bolgurtseva

Yulia Gavrilova

Zhenya Vinogradov

Alexander Bantyev

Stepan Prudnikov

Moremi Vannak

Fedor Fedorov

Krisztián Ádám

Alyona Antonova

Artem Yurchenko

Diogo Castro

Heitor Toledo Lassarote de Paula

Ilona Prikule

Natalya Kokova

Daria Smirnova

Serokell PR

Gints Dreimanis

Ivan Markov

Andrey Demidenko

Dmitriy Mozhevitin

Iurii Kravchenko

Vlad Shcherbina

Preetham Gujjula

Dina Safullina

Alexey Khaciyants

Dmitri Puzyrev