Victor Blaga, Developer in Munich, Bavaria, Germany
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Victor Blaga

Verified Expert  in Engineering

Software Developer

Munich, Bavaria, Germany
Toptal Member Since
July 9, 2020

Victor is a versatile software engineer with more than 12 years of professional experience, specializing in full-stack web development, cloud platforms, and information systems. He is fluent in most major languages (JavaScript, Python, Java, C#, and Ruby) and related frameworks. Victor continuously strives to improve his craft by studying new methods and technologies. For example, Victor thinks that Clojure is the best, most under-appreciated programming language out there.


Fortune 100 Construction and Farm Machinery Maker (via Toptal)
Amazon Web Services (AWS), SQL, Azure DevOps, Snowflake, AWS Lambda...
SQL, Apache Kafka, Kubernetes, JavaScript, C#.NET, Agile Software Development...
Scalable Capital
SQL, Amazon Web Services (AWS), JavaScript, Agile Software Development, Redux...




Preferred Environment

Slack, Git, Visual Studio Code (VS Code), JetBrains, Linux

The most amazing...

...thing I've built is an end-to-end review analysis system for the hotel review platform Trivago, powered by NLP and machine learning.

Work Experience

Tech Lead

2020 - 2021
Fortune 100 Construction and Farm Machinery Maker (via Toptal)
  • Developed a rule engine for high-throughput streaming status messages that performs data quality validation according to predefined business rules.
  • Extended technical and architectural support to the project manager and various other business stakeholders.
  • Provided mentorship and technical assistance to a team of four developers and pushed for and ensured high standards for code quality and software development practices.
Technologies: Amazon Web Services (AWS), SQL, Azure DevOps, Snowflake, AWS Lambda, Amazon Kinesis, Java, Agile Software Development, Technical Leadership

Freelance Senior Developer (Java, C#, and OpenShift)

2018 - 2020
  • Implemented an automated goods-receipt process that checks the validity of the documents presented by a truck driver upon entering the premises of a BMW plant, reducing the previous manual process effort to almost zero.
  • Developed several of the connected supply chain apps used by the BMW material planning and logistics department to track the status of parts deliveries, increasing the employee's efficiency in tracking and managing the delivery process.
  • Improved the efficiency and cost of the BMW live delivery tracking solution. For example, reduced the database costs from $4,000 per month to $300 per month.
  • Developed a Java-based orchestrator service coordinating communication with various external services within the quality assurance/reclamation department, providing adapters for HTTP/REST, Apache Kafka, and SAP RFC.
Technologies: SQL, Apache Kafka, Kubernetes, JavaScript, C#.NET, Agile Software Development, OpenUI5, OpenShift, Azure, C#, Jakarta EE, Java

Senior Developer

2017 - 2018
Scalable Capital
  • Contributed to various features related to Scalable Capital's back-end Java-based API and its React/Redux front-end application.
  • Migrated a batch job solution from Spring Batch to AWS CloudWatch Events which increased the efficiency of these jobs and reduced the complexity related to locking and synchronization.
  • Proposed and prototyped an Apache Kafka-based alternative solution for storing financial transaction data.
Technologies: SQL, Amazon Web Services (AWS), JavaScript, Agile Software Development, Redux, React, Spring Boot, Java

Tech Lead Search Engineering | Lead Engineer Review Analysis

2015 - 2017
Trivago GmbH
  • Developed a hotel review scraping solution that extracted reviews from more than ten review websites and for 500,000+ hotels while also aggregating and storing a total of 10 million+ reviews.
  • Designed and developed a machine learning experimentation and integration platform used by the data science team to test and fine-tune hundreds of review analysis machine learning model variants each day.
  • Implemented a review labeling web application used by linguists to generate more than 10,000+ data points used for training machine learning algorithms.
  • Developed an automated and auto-scalable solution able to perform ML-based review classification on the entire 10 million+ hotel review dataset in a couple of hours.
  • Implemented and maintained a search index solution serving 100+ million of daily search queries.
  • Developed a novel phrase search query index capable of handling 10,000+ complex/rich natural language daily search queries, such as "hotels with a great pool in Milano."
Technologies: SQL, Data Science, Apache Kafka, Apache Solr, Machine Learning, Flask, Amazon Web Services (AWS), Ruby, Agile Software Development, Spring Boot, Elasticsearch, Solr, Apache Lucene, Java, Ruby on Rails (RoR), Scikit-learn, Keras, Natural Language Toolkit (NLTK), Python, Technical Leadership

Senior Full-stack Developer | Data Scientist

2013 - 2015
Reputami GmbH
  • Implemented Ruby-based web scrapers for eight hotel review websites, aggregating 10,000+ reviews for 100+ customers.
  • Implemented the main Reputami website: a Ruby on Rails website generating HTML on the server that was used by more than 100 paying customers.
  • Designed, tested, and implemented machine learning algorithms to analyze and extract categorical and polarity classifications from more than 10,000 hotel reviews.
Technologies: SQL, Data Science, Machine Learning, Ruby, Agile Software Development, jQuery, Microsoft Azure, Scikit-learn, Natural Language Toolkit (NLTK), Python, Nokogiri, Ruby on Rails (RoR)

Data Quality Rule Engine

A Java-based stream processor that enforced business rules validations on status messages generated by the assets of the client. I was the tech lead of a team of 4 developers that implemented a rule-engine capable of validating business rules on high-throughput streaming data. Our main challenges were stateful stream processing under high load (more than 50 messages per second) and also achieving and maintaining a high team velocity, as we implemented close to 100 business rules in a relatively short time.

Because of sound architectural decisions and solid development practices, the project was a great success and the client was very happy with our team's performance.

End-to-end Hotel Review Analysis Pipeline for Trivago

A mostly Python (and some Ruby on Rails) project, hosted on AWS, to scrape hotel reviews from various review websites (e.g., TripAdvisor,, Expedia, and so on), and run them through machine-learning-based natural language processing algorithms.

The goal was to extract topic-based scores from the textual reviews and aggregate them into a global hotel category score, e.g., a review such as "the hotel was close to the city center" would score "good" on the "location" topic and would contribute positively to the global hotel location score.

I was the lead engineer, responsible for implementing the scrapers, the analysis modules, and the infrastructure components around them. I also had to coordinate with various project stakeholders and contributors, including data scientists - to integrate the ML models and with product owners - to calibrate scoring aggregation methods.

I also designed and developed a couple of tools around the main project: an experimentation tool used by data scientists to iterate and fine-tune models and a classification tool used by language experts to generate training data.

Goods Receipt Automated Process for BMW, Munich

A Java-based REST service—hosted on OpenShift and Kubernetes—to automatize and reduce to a minimum the manual labor involved in the goods-receipt process at manufacturing plants.

I coordinated with business stakeholders to refine and implement business requirements and with SAP specialists to define data selection processes. I was the primary (and only) developer on this project.

The Website
A Ruby on Rail server-side rendering website, where I was the main back-end developer and coordinated with the designer to build the HTML views. I was also responsible for the front-end JavaScript development—implemented with jQuery—providing features such as automatic-refresh, infinite scrolling, and so others.

Additionally, I build web scrapers capable of retrieving social media reviews for various hotel and restaurant websites as well as a machine learning-based natural language processing module capable of analyzing textual reviews and deriving categorical scores.


Java, C#.NET, Python, SQL, JavaScript, Ruby, C#, Snowflake


Agile Software Development, Data Science, Azure DevOps, REST


Ruby on Rails (RoR), Flask, Spring Boot, Redux


React, Apache Lucene, jQuery, Natural Language Toolkit (NLTK), Keras, Scikit-learn, Nokogiri


Apache Solr, JetBrains, Git, Slack, OpenUI5, Solr


OpenShift, Kubernetes, Apache Kafka, Amazon Web Services (AWS), Linux, Jakarta EE, Azure, AWS Lambda, Docker, Visual Studio Code (VS Code)


Natural Language Processing (NLP), Software Architecture, Data Engineering, Technical Leadership, GPT, Generative Pre-trained Transformers (GPT), Machine Learning, Microsoft Azure, Amazon Kinesis, Machine Language


Elasticsearch, Amazon DynamoDB, PostgreSQL

2010 - 2014

Master's Degree in Computer Science

University of Bonn - Bonn, Germany

2006 - 2010

Bachelor's Degree in Automatic Systems

University of Transylvania - Brasov, Romania

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