Nicolai Negru, Developer in London, United Kingdom
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Nicolai Negru

Verified Expert  in Engineering

Back-end Developer

London, United Kingdom

Toptal member since February 26, 2024

Bio

Nicolai is a seasoned back-end developer and data engineer who excels in Python and SQL. With 12 years of Python expertise, he refactored the legacy codebase at BNP Paribas, enhancing performance and reducing duplication. At Pret A Manger and Marks & Spencer, he implemented Databricks pipelines for real-time reporting on sales and personalized shopping recommendations. Nicolai is a pragmatic advocate of code readability and modularity and appreciates the importance of clear communication.

Portfolio

BNP Paribas CIB
Python, Oracle, IBM MQ, Database Design, RPC, APIs, Back-end Development...
Equal Experts
Python, FastAPI, SQLAlchemy, Oracle, JavaScript, OAuth 2, HTML5...
Marks and Spencer
Python, Databricks, Azure Data Factory (ADF), Azure Key Vault, PySpark...

Experience

  • Python - 12 years
  • SQL - 8 years
  • Process Improvement - 6 years
  • RESTful Microservices - 5 years
  • Pandas - 3 years
  • FastAPI - 2 years
  • PySpark - 1 year
  • Databricks - 1 year

Availability

Full-time

Preferred Environment

Databricks, Python, SQL, Go, PySpark, FastAPI

The most amazing...

...thing I've done is work on a legacy codebase that became difficult to change and evolve—giving it a second life by restructuring and improving performance.

Work Experience

Senior Python Developer

2023 - PRESENT
BNP Paribas CIB
  • Refactored large sections of the legacy codebase to reduce code duplication and improve performance.
  • Reviewed the existing monorepo of a trade risk assessment system. Designed and proposed a new architecture, splitting it into a series of specialized microservices to improve modularity and simplify the implementation of new functional requirements.
  • Implemented automated database versioning, which allowed the deployment and rollback of database changes as part of each release.
Technologies: Python, Oracle, IBM MQ, Database Design, RPC, APIs, Back-end Development, Performance Optimization, Technical Leadership, Scalability, SQL, Unit Testing, Pytest, Back-end, Code Refactoring, JSON, ETL

Python Engineer

2022 - 2023
Equal Experts
  • Designed and implemented a web application that allowed delivery leads to report on their project's progress and give senior management a clear picture of which projects need assistance to stay on track and within the budget.
  • Integrated the in-house web application with 3rd-party APIs and systems for authentication and data exchange.
  • Created and implemented a PoC synthetic data generator application, which accepted data schema definition and generated large volumes of data per the requested shape, format, and volume.
  • Profiled and optimized the performance and memory footprint of Python applications.
Technologies: Python, FastAPI, SQLAlchemy, Oracle, JavaScript, OAuth 2, HTML5, Database Design, Python Asyncio, REST APIs, APIs, RESTful Services, Back-end Development, Asynchronous Programming, Performance Optimization, Technical Leadership, SQL, Unit Testing, Pytest, Back-end, Code Refactoring, JSON, Jupyter, ETL

Senior Python Developer

2022 - 2022
Marks and Spencer
  • Maintained and expanded web APIs, processing streams of events from customers navigating the client's website.
  • Implemented Databricks pipelines, processing incoming data streams from customers browsing the retailer's website to generate shopping recommendations for customers based on historical shopping patterns.
  • Provided on-call technical support to the developers consuming our web APIs and data scientists working with our Delta Lake.
Technologies: Python, Databricks, Azure Data Factory (ADF), Azure Key Vault, PySpark, Delta Lake, Apache Kafka, REST APIs, APIs, RESTful Services, Back-end Development, Asynchronous Programming, Technical Leadership, Scalability, SQL, PostgreSQL, Unit Testing, Pytest, Back-end, Code Refactoring, JSON, Jupyter, Data Engineering, ETL

Python Engineer

2021 - 2022
Equal Experts
  • Performed a complete inventory of the existing data pipelines and prepared blueprints for senior management.
  • Redesigned the data platform to match the company's business needs and technical capabilities, demonstrating to the business and technical groups how new architecture could be used and scaled to accommodate new data feeds.
  • Implemented the streamlined platform, consuming several streaming and batched data feeds, and handed it over to the technical teams for further expansion.
Technologies: Python, Databricks, Azure Data Factory (ADF), PySpark, Azure Key Vault, Delta Lake, APIs, RESTful Services, Technical Leadership, Scalability, SQL, PostgreSQL, Unit Testing, Pytest, Back-end, Code Refactoring, JSON, Data Engineering, ETL

Python Developer

2021 - 2021
Essentia Analytics
  • Maintained and expanded web APIs and data pipelines, consuming trading data to identify traders' behavioral patterns.
  • Worked with data scientists to analyze traders' performance in light of historical market conditions and issue behavioral recommendations to increase traders' efficiency.
  • Onboarded new data feeds, troubleshooted daily data issues, and improved code efficiency and readability.
Technologies: Python, Pandas, Amazon EC2, Amazon RDS, PostgreSQL, AWS Lambda, AWS AppSync, GraphQL, REST APIs, APIs, RESTful Services, Asynchronous Programming, Performance Optimization, Technical Leadership, Scalability, SQL, Unit Testing, Pytest, Back-end, Code Refactoring, Amazon Web Services (AWS), JSON, Data Engineering, ETL

Senior Python Developer

2020 - 2021
Secure Thingz
  • Developed and maintained Secure Boot Manager for embedded devices, protecting companies developing IoT software against the unauthorized distribution of their products.
  • Profiled and optimized the performance of Python-based software packages.
  • Improved CI/CD pipelines with TeamCity and championed test-driven development and pair programming.
Technologies: Python, TeamCity, Performance Optimization, Technical Leadership, Unit Testing, Pytest, Code Refactoring

Experience

Functionality Modernization and Expansion

Modernized and expanded an application's functionality as a senior Python engineer, quantifying the risk of trades that, according to legislation, must be cleared via clearinghouses.

I enabled the automatic assessment of trades in several stages, starting with fast conservative estimates and progressively including more detailed information when more precise margins have to be calculated. I used technologies such as Python, Oracle Database and SQL, IBM MQ, event-driven architecture, XML, and FpML.

Web Application Development

A web application for project progress tracking that I designed and implemented as a Python engineer.

The web application enabled delivery leads to report on the progress of their projects—providing senior management with a clear view of which projects are on track and within budget. I also integrated 3rd-party APIs and systems for authentication and data exchange.

Additionally, I designed and implemented a PoC synthetic data generator application that accepted data schema definitions, including shape, format, and volume, and generated large volumes of data per the requirements. I used Oracle Database, JavaScript, HTML, OAuth 2, and Python technologies such as FastAPI, SQLAlchemy, and pandas.

Web API Expansion and Pipelines Implementation

Web APIs that processed event streams from customers navigating a large retailer's website.

As a senior Python engineer, I maintained and expanded the web APIs, pushing incoming data streams through Databricks pipelines and generating shopping recommendations to be displayed to customers based on the analysis of historical shopping patterns. I used PySpark, pandas, Azure Databricks and Data Factory, Kafka, MongoDB, and Kubernetes.

Data Pipelines Inventory and Platform Redesign

A thorough review of existing data pipelines, which the company could not maintain and evolve because of their complexity.

After the inventory, I also redesigned the data platform as the Python data engineer on the project, matching the company's business needs and technical capabilities. The new architecture demonstrated to the business and technical groups how it could be scaled to accommodate new data feeds. Finally, I implemented the streamlined platform that consumed several streaming and batched data feeds, which the technical teams could further expand. I used PySpark, pandas, Delta Lake, and Azure: Databricks, Data Factory, and Key Vault.

Web API Expansion for Trading Data Consumption

Web APIs and data pipelines that consumed trading data to identify traders' behavioral patterns.

I maintained and expanded the web APIs and data pipelines, analyzing traders' performance in light of historical market conditions to issue behavioral recommendations for increased traders' efficiency. I used pandas and Amazon: EC2, RDS for PostgreSQL, S3, Lambda, and AppSync.

Education

2018 - 2020

Diploma in Software Development

Code Institute - London, UK

2009 - 2011

Master's Degree in Business Administration (MBA)

Cass Business School (now Bayes Business School) - London, UK

Certifications

DECEMBER 2024 - DECEMBER 2027

AWS Certified Developer - Associate

AWS

MAY 2023 - PRESENT

Ultimate Go

Ardan Labs

JULY 2012 - PRESENT

Certified Tester Advanced Level Test Manager (CTAL-TM)

ISTQB

JANUARY 2009 - PRESENT

PRINCE2 Certification

APMG International

Skills

Libraries/APIs

Pandas, PySpark, SQLAlchemy, Python Asyncio, REST APIs

Tools

Pytest, IBM MQ, Azure Key Vault, AWS AppSync, TeamCity, Jupyter, AWS IAM, Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (SNS)

Languages

Python, SQL, XML, Go, JavaScript, HTML5, GraphQL

Paradigms

Database Design, Asynchronous Programming, Unit Testing, Code Refactoring, ETL

Platforms

Databricks, Oracle, Apache Kafka, Kubernetes, Amazon EC2, AWS Lambda, Amazon Web Services (AWS)

Storage

PostgreSQL, JSON, MongoDB, Amazon S3 (AWS S3), Amazon DynamoDB

Frameworks

OAuth 2, Blueprint

Other

Test Management, QA Automation, Consulting, Process Improvement, RESTful Microservices, IT Project Management, FastAPI, Delta Lake, APIs, RESTful Services, Back-end Development, Back-end, Data Engineering, Azure Data Factory (ADF), RPC, Amazon RDS, Performance Optimization, Technical Leadership, Scalability, Amazon API Gateway

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