Alejandro Santos, Software Developer in Slough, United Kingdom
Alejandro Santos

Software Developer in Slough, United Kingdom

Member since January 3, 2020
Alejandro is a computer scientist and software professional with an MSc in computer science. Over the past 15 years, Alejandro's worked on several projects in a variety of industries—including the private sector, scientific endeavors, and research—for a range of companies and institutes including CERN, where he recently developed software in Java and integrated it in a database system while working agile. Alejandro enjoys working within distributed teams and values clear communication.
Alejandro is now available for hire


  • Kayenta Ltd
    ETL, Ansible, Terraform, CI/CD Pipelines, Testing, Azure Table Storage, Azure...
  • Toptal Client
    Microservices, Spring, Java
  • Codigo Delta
    Distributed Systems, JSON Web Tokens (JWT), Auth, Hibernate, JPA, JEE...


  • Java 14 years
  • Python 14 years
  • Object-oriented Programming (OOP) 12 years
  • SQL 12 years
  • Algorithms 10 years
  • Networking 10 years
  • Data Structures 10 years
  • C++ 10 years


Slough, United Kingdom



Preferred Environment

Git, C++, Java, Python, Linux

The most amazing...

...project I've worked on is a social networking website for people in my hometown. This was long before Facebook and Instagram existed.


  • Tech Lead

    2020 - PRESENT
    Kayenta Ltd
    • Led and managed the team development effort following an Agile structure.
    • Coordinated the testing effort following Unit Testing and End to End testing.
    • Designed and created new microservices with a REST API for internal usage.
    • Designed and created new ETL pipelines to consume customer's data.
    Technologies: ETL, Ansible, Terraform, CI/CD Pipelines, Testing, Azure Table Storage, Azure, Python 3
  • Senior Software Engineer

    2020 - 2020
    Toptal Client
    • Updated a REST API endpoint to provision new business requirements.
    • Created unit tests using JUnit for the new REST API endpoints.
    • Tracked work using Jira and interacted with the team using GitHub and Slack.
    • Created a parser for a domain-specific language (DSL) using ANTLR4.
    Technologies: Microservices, Spring, Java
  • Founder

    2019 - 2020
    Codigo Delta
    • Created the early vision of, a platform for learning programming, data structures, and algorithms.
    • Defined the roadmap along with maintaining and prioritizing the backlog.
    • Created and implemented the basic architecture of the MVP.
    • Wrote the problem statements, testing environment, and test cases.
    • Built a Jenkins pipeline in a Docker container that runs unit tests, integration tests, and end-to-end tests along with building new containers and deploying new application versions.
    • Implemented the automated back-end task solver in Python.
    Technologies: Distributed Systems, JSON Web Tokens (JWT), Auth, Hibernate, JPA, JEE, HATEOAS, RESTful APIs, Maven, Spring Boot, Java, TypeScript
  • Tech Lead and Researcher in Computer Science

    2016 - 2019
    CERN (The European Organization for Nuclear Research)
    • Implemented both a type of simulation software in C++11 and small-scale prototypes in C++ and Python to model a very large data acquisition system.
    • Defined the roadmap of the project as well as maintaining and prioritizing the backlog.
    • Tracked and fixed bugs using Jira as a reporting tool.
    • Published the scientific works underlying the problem statement.
    • Gave presentations about the project both internally and at conferences.
    • Implemented data analysis and reporting metrics using Python, Matplotlib, and NumPy.
    Technologies: Distributed Systems, OMNeT++, Python, C++
  • Software Engineer

    2014 - 2016
    CERN (The European Organization for Nuclear Research)
    • Created a testing environment for a complex event processing (CEP) expert/streaming system.
    • Developed the cross-language access bindings (C++ to Java) for the time-series database connection.
    • Designed and implemented an efficient algorithm to read a large amount of data from the database.
    • Defined the software technologies that were required to solve the problem.
    • Published a scientific paper describing the algorithms and testing strategy.
    • Tracked and fixed bugs using Jira as a reporting tool.
    • Wrote the documentation of the project and prepared internal reference materials.
    • Maintained and prioritized the work backlog for the project.
    • Conducted user interviews and usability testing.
    • Implemented the web-based version of the project using Python for the back end.
    Technologies: NoSQL, DB, Distributed Systems, Streaming, Complex Event Processing (CEP), C++, Python, Java
  • Assistant Professor

    2010 - 2013
    Universidad Nacional de La Plata
    • Taught courses in Java programming and Python programming.
    • Wrote the exams for the Data Structures and Algorithms course.
    • Wrote the assignments and learning materials for the Java programming labs.
    • Organized the local university's seat of ACM/ICPC: a national programming contest.
    Technologies: Algorithms, Data Structures, Java
  • Software Engineer

    2010 - 2011
    • Developed and tested an internal web Java app to keep track of job applicants.
    • Developed and tested a functionality for a Ministry of Health's project to keep track of the compliance of several health regulations.
    • Refactored legacy modules to improve the maintenance and addition of new features for the client's needs.
    Technologies: Hibernate, JEE, Seam, Java
  • Security Analyst

    2009 - 2010
    • Developed an internal app (Flask and SQLAlchemy) to automatize the tracking of spam sources.
    • Conducted user interviews and security-related usability testing.
    • Performed security reviews of services running on the external network.
    • Carried out penetration testing on a variety of web applications.
    • Administered services and performed DevOps duties.
    • Conducted research and contributed to the development of honeypot software products and solutions.
    • Performed a forensic analysis on infected servers and wrote reports on the findings as well as recommendations for future operations.
    • Implemented firewall hardening and network traffic analyses.
    Technologies: Distributed Systems, Networking, Security, Python
  • Software Engineer

    2009 - 2009
    Mercurial | Google Summer of Code
    • Implemented the basic functionality to migrate the Python 2 codebase to Python 3.
    • Worked in a collaborative and distributed team on an open-source project.
    • Communicated the required changes for the migration of the codebase in the public mailing list of the project.
    Technologies: Mercurial, Python 3
  • Founder | CTO

    2003 - 2009
    La Plata Nights
    • Created the early vision of, a social media platform about the nightlife in the city of La Plata, Argentina.
    • Conducted user interviews and usability testing of the platform.
    • Defined the roadmap, kickstarted development, and maintained and prioritized the backlog.
    • Created and implemented the basic architecture of the MVP.
    • Refactored the application multiple times to be able to handle the growing load.
    Technologies: MySQL, JavaScript, PHP
  • Software Engineer

    2007 - 2008
    • Developed custom features based on the requirements outlined by the clients.
    • Tracked and fixed bugs, documented development tasks in an internal Wiki using Trac.
    • Performed several maintenance tasks on the internal network, administered web services and the source code version control server.
    • Wrote documentation on the usage of the custom features of the product.
    Technologies: Enterprise Resource Planning (ERP), Object-relational Mapping (ORM), PostgreSQL, Java
  • Intern

    2005 - 2006
    • Developed a functionality for an application to help with the administration of a hospital.
    • Implemented modules to produce customized reports.
    • Conducted research and contributed to the development of distributed systems and databases.
    • Taught Pascal programming to students in a course called Introduction to Programming.
    Technologies: JavaScript, MySQL, PHP


  • (Development)

    Código Delta is a platform for learning programming, data structures, and algorithms with a focus on the Spanish-speaking people of the world. Users can solve programming tasks online and review their submissions in order to improve their coding skills.

  • The Despacito Programming Language (Development)

    Despacito is a programming language following the Latin-American culture. It is an open-source and free software (BSD license). Despacito is Turing-complete, compiled, statically typed, and supports arrays, functions, and recursion. The Despacito compiler is implemented in Python 3 in about 1,000 lines of code, without using any external libraries (e.g., parser generators) or regular expressions. The source code is available at GitHub.

  • Dakara Online MMORPG (Development)

    Dakara Online is a C++ 11 migration of the game server-code for Argentum Online, the first MMORPG developed by South American developers. The game was very popular in its time (2002+) and was made open source around the same time.
    The Dakara Online game server in a source-to-source translated version of the game server, from VB6 to C++. The Dakara game server was hosted on AWS between 2014 and 2016.


  • Languages

    Python, Java, C++11, C++, SQL, Python 3, C++14, C++17, C, Embedded C++, Embedded C, TypeScript, Haskell, JavaScript, Scala, PHP, Lua
  • Paradigms

    Object-oriented Programming (OOP), Test-driven Development (TDD), Unit Testing, Agile Software Development, Functional Programming, Microservices, REST, Agile, Testing, Refactoring, Compiler Design, Object-relational Mapping (ORM), Data Science, ETL, Serverless Architecture
  • Platforms

    Docker, Linux, Ubuntu, Amazon Web Services (AWS), Embedded Linux, Jupyter Notebook, Amazon, JEE, Azure, Kubernetes, AWS Lambda, Google Cloud Platform (GCP)
  • Storage

    JSON, Relational Databases, MySQL, PostgreSQL, Redis, DB, NoSQL, Azure Table Storage
  • Other

    Data Structures, Algorithms, Networking, APIs, Back-end Development, Back-end, Attention to Detail, Distributed Systems, Distributed Messaging, Software Engineering, Startups, RESTful APIs, RESTful Microservices, Code Architecture, Code Refactoring, MMORPGs, 2D Games, Storage, Embedded Systems, Serverless, Distributed Software, Economics, Finance, Data Analysis, Statistics, Object-oriented Databases, Relational Algebra, Machine Learning, RESTful Services, Spring Cloud, AWS, Cloud, Cloud Computing, Cloud Security, Cloud Storage, Mercurial (Hg), Compilers, Complex Event Processing (CEP), Streaming, HATEOAS, Enterprise Resource Planning (ERP), Research, Data, CI/CD Pipelines, Embedded Software, Containers
  • Frameworks

    Spring, Spring Boot, Django, Boost, JNI, OMNeT++, JPA, Hibernate, JSON Web Tokens (JWT), Seam, Selenium
  • Libraries/APIs

    REST API, Jenkins Pipeline, OpenCV, REST APIs, Auth, React
  • Tools

    Git, Jenkins, ANTLR 4, CMake, Zuul, GitLab, GitLab CI/CD, Maven, Mercurial, Terraform, Ansible
  • Industry Expertise

    Accounting, Marketing, Security


  • Master of Business Administration (MBA) in Business Administration
    2019 - 2020
    Quantic School of Business and Technology - Remote
  • PhD (Thesis Writing in Progress) in Computer Science
    2016 - 2019
    Ruprecht Karl University of Heidelberg - Heidelberg (Germany) and Geneva/CERN (Swizerland)
  • Licenciatura en Informatica (equivalent to an MSc degree) in Computer Science
    2003 - 2015
    Universidad Nacional de La Plata - La Plata, Argentina
  • Analista Programador Universitario (equivalent to a BSc degree) in Computer Science
    2003 - 2012
    Universidad Nacional de La Plata - La Plata, Argentina


  • Getting Started with AWS Machine Learning
    MAY 2020 - PRESENT
  • AWS Fundamentals: Going Cloud-Native
  • Microservices with Spring Cloud

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