Rafael Kallis

Creating value from disruption.


I am a software engineer working on projects that combine engineering, disruptive technologies and business. My homebase is located at Zurich, Switzerland and my main clients are financial technology businesses. Over the years I have developed a skillset in fullstack and blockchain software development, as well as data science expertise. Outside my industry activities I also author and review academic papers.

Clients and Projects

logo of bob finance

Bob Finance, Software Engineering Consultant, 2020-

Payment and financing solutions for private individuals and companies.
Internal financing application dashboard for customer support and risk management.
Partner dashboard for retailers to provide 'buy now, pay later' solutions.
Client dashboard for customers access.
Migration of legacy loan management system to a modern cloud banking platform.
C# Identity Server Typescript React Cypress Azure AD Postgres SQL Server Azure Devops
logo of valdon group

Valdon Group, Software Engineering Consultant, 2020-

Consultancy and software services in the field of financial technology.
Working a market maker that arbitrates across orderbook (centralized) and liquidity-pool (decentralized) based markets.
Implemented a machine-learning pipeline for aggregating a very large dataset efficiently, based on statistical network analysis algorithms.
Developer near-shoring, talent scouting and acquiring.
C# Python NetworkX Solidity Ethereum
logo of hederastarter

HederaStarter, Software Engineering Consultant, 2022-

Tokenized innovation incubator and community oriented launchpad.
Launchpad dapp development.
Developing a realtime hashgraph transaction log tracker.
Researching integration of ethereum json-rpc compatible wallets to hedera dapps.
Solidity Hedera Hashgraph Go Clickhouse Typescript React
logo of bravo one

Bravo One, Partner, 2020-

Employee recognition and reward system for the tourism industry.
Review mining, word embeddings, dimensionality reduction, feature engineering.
Automated human review collection from TripAdvisor, Booking.com and Google Maps.
Product owner of native app, web app and backend.
Interactions with B2B partners for api integrations.
Python SpaCy Typescript React Node.js
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Ticket Tagger, Researcher, Maintainer, 2019-

Automated github issue type classification bot.
Developing a github bot that utilizes machine learning and word embedding techniques to automate the issue classification process on github.
Authored journal and conference papers on automated issue type prediction of software repositories.
Python FastText Typescript Node.js
logo of covee network

Covee Network, Partner, 2020-2021

Decentralized collaboration and reward platform for knowledge workers.
Co-product owner and engineer over frontend, backend and smart contracts.
Mechanism design of Covee's decentralized reward distribution mechanism.
Typescript React Solidity Ethereum Node.js NestJS Postgres
logo of occam x

OccamX, Software Engineering Consultant, 2021

Decentralized exchange for Cardano native tokens.
Liquidity pool dapp development.
Typescript React Solidity Milkomeda

Academic Work

cover page of nlbse paper

NLBSE'22 Tool Competition, Co-Chair, 2022

IEEE/ACM 1st intl. workshop on Natural Language-Based Software Engineering (NLBSE).
Competition on github issue type prediction performance.
Dataset encompassing 800 thousand github issues.
Five team submissions, eleven models evaluated.
Benchmark Natural language processing Software maintenance and evolution
cover page of kallis paper

Predicting issue types on GitHub, First Author, 2021

Published in the Journal of Science of Computer Programming.
Tool paper on automated github issue prediction.
Empirical evaluation on 30 thousand github issues.
Software maintenance and evolution Issue reports management Labeling unstructured data
cover page of journal

Reviewer, 2021-

Workshop on Natural Language-based Software Engineering.
Software maintenance and evolution Issue reports management

Recent Good Reads

book on factor investing

Your Complete Guide to Factor-Based Investing, Berkin and Swedroe

Distilled Research Personal Finance Factor Investing
book on math

Weapons of Math Destruction, Cathy O'Neil

Model Bias Impact of Science Responsible Data Mining
book on randomness

Fooled by Randomness, Nassim Nicholas Taleb

Luck and Uncertainty Stories Personal Finance