Haider is available for hire

Haider Ali Agha

Verified Expert in Engineering

Python Developer

Dublin, Ireland

Toptal member since February 21, 2021

Expertise

Algorithms Integration API Python REST API JSON .NET C#Web Development Code Review System Security Back-end Developers

Bio

Haider is a back-end developer who uses REST APIs to build great developer experiences. He has developed SDKs and documentation that power dozens of API programs globally and are used by thousands of developers. During his time at APIMatic, he helped major companies such as Sabre Corporation and Bandwidth maximize the developer experience for their REST APIs. He is now looking to share his expertise with a broader audience.

Portfolio

Indeed

Python 3, Software Architecture, Scripting, Automation, SQL, Datadog, PagerDuty...

Databricks

Python, REST APIs, Spark, Jira REST API, PySpark, Pandas, Jira, DevOps, ETL...

Navarc

Python, Git, Google Cloud, Google Cloud Functions, Google BigQuery, APIs...

Experience

Python - 8 years
Git - 6 years
REST APIs - 5 years
Postman - 4 years
Java - 3 years
API Documentation - 3 years
C#.NET - 3 years
Google Cloud Platform (GCP) - 1 year

Preferred Environment

Windows, Visual Studio, Visual Studio Code (VS Code), Jira, Slack, C#.NET, Git, Python, Google Cloud Platform (GCP), Microsoft Excel

The most amazing...

...product I've developed is version 3 of APIMatic's SDKs, which incorporate three years' worth of learning and customer feedback to offer an enhanced experience.

Work Experience

Software Engineer (SRE)

2023 - 2025

Indeed

Designed and implemented performance and reliability improvements across 30+ Java/Python services and 100+ scheduled workloads, improving scalability and operational stability.
Developed custom Python-based observability and log analysis tooling for large-scale production debugging and incident investigation.
Fixed critical bugs in production Python and Java services while on call.
Used AI-assisted development tools, including Cursor and Claude Code, for software development, debugging, operational analysis, and developer productivity improvements.
Led the design and execution of performance and scalability improvements across multiple engineering teams.
Optimized Amazon Aurora MySQL infrastructure for cost and performance across production systems.
Added Datadog RUM to multiple React apps to bring error reporting closer to the end user’s experience.
Right-sized deployments and configured HPA to reduce cost without compromising on performance.
Aided the migration from on-prem to the cloud by using Datadog metrics to find traffic to on-prem services and updating said services to target cloud deployments.
Used Terraform to set up dashboards, monitors, and SLO alerts on Datadog to provide monitoring in a manner that is sustainable for the product team to maintain.

Technologies: Python 3, Software Architecture, Scripting, Automation, SQL, Datadog, PagerDuty, Terraform, APIs, Logging, Software Design, Architecture, Visual Studio Code (VS Code), Pytest, Amazon RDS, Amazon Web Services (AWS), Amazon S3 (AWS S3), Automations, Jira, JavaScript, Django, CSV File Processing, Data Extraction, Beautiful Soup 4, Real-time Data, Scraping, Web Scraping, Refactoring, Microsoft Excel, Data Analysis, Google Sheets, Claude Code

Software Engineer

2022 - 2023

Databricks

Developed a pipeline on Databricks to manage tickets on Jira for vulnerabilities found by Qualys and Dependabot and for compliance reports generated by Qualys.
Implemented caching and batch processing to speed up processing and reduce database reads and writes.
Created an error handling and alerting framework to allow the pipeline to continue when facing non-fatal errors and to exit gracefully when facing fatal errors.
Automated the generation of the monthly plan of actions and milestones (POAM) reports, replacing a manually created CSV with a Google Sheet automatically created within the appropriate folder in Google Drive.
Triaged the vulnerability scan results from multiple APIs to provide a unified view.

Technologies: Python, REST APIs, Spark, Jira REST API, PySpark, Pandas, Jira, DevOps, ETL, Databricks, CI/CD Pipelines, Software Development Lifecycle (SDLC), Google Drive API, Google Sheets API, Logging, Databases, Automation Scripting, Software Engineering, Algorithms, Integration, Visual Studio Code (VS Code), Pytest, Automations, Third-party APIs, CSV File Processing, Data Extraction, Real-time Data, Google Sheets

Software Engineer

2021 - 2022

Navarc

Built scalable cloud-native data ingestion pipelines integrating Amazon SP-API and Walmart Marketplace APIs.
Re-architected the platform from VM-based infrastructure to event-driven Google Cloud Functions, reducing infrastructure costs by 90% while improving scalability.
Developed an automated system to trigger Google Functions using Google Cloud Scheduler and Google Pub/Sub.
Added error logging from Google Cloud Functions to Slack, allowing developers to become aware of problems immediately.
Used Pandas to clean, filter, and aggregate data before loading it to BigQuery.
Modularized the program, reducing code duplication by over 70%.

Technologies: Python, Git, Google Cloud, Google Cloud Functions, Google BigQuery, APIs, PostgreSQL, SQL, Amazon API, Walmart API, Pandas, CSV, JSON, Slack, Slack API, Amazon Product Advertising API, Postman, Google Cloud Platform (GCP), PIP, Automation, API Integration, Serverless, ETL, Code Review, Source Code Review, Automation Scripting, Scripting, Software Engineering, Algorithms, NumPy, Integration, RESTFul APIs, API Development, Docker, DevOps, Visual Studio Code (VS Code), Pytest, Ubuntu, Automations, Pub/Sub, Third-party APIs, Data Extraction, Real-time Data, Refactoring, Webhooks

Python Developer

2021 - 2021

Cerm

Developed a REST API using Python to access the client's SQL Server database.
Used the Eve framework for Python to simplify API design, allowing the team to maintain and extend the API with only a basic knowledge of Python and APIs.
Described the REST API using OpenAPI Specification to allow testing with Postman and documenting with Swagger.
Created integration tests to ensure that the API functioned as expected.

Technologies: Python, Python 3, PIP, Postman, APIs, API Design, REST, REST APIs, JSON, JSON REST APIs, SQL, Microsoft SQL Server, Flask, OpenAPI, Software Engineering, RESTFul APIs, API Development, Visual Studio Code (VS Code), Eve, SQLAlchemy, Pytest

Lead Software Engineer

2020 - 2021

APIMATIC

Managed the team responsible for APIMatic's Code Generation Engine, which powers SDKs deployed by dozens of API providers and used by thousands of developers.
Divided the core team’s yearly tasks into fortnightly sprints to ensure that monthly deadlines were met using Jira.
Added XML parsing to Python and Ruby SDKs to support REST APIs that transfer data using XML.
Integrated Bitbucket, Jenkins, and Myget to automate the testing and deployment of the code generation project.
Managed monthly and quarterly deliveries for enterprise customers such as Bandwidth and Sabre Corporation.
Onboarded two new members to the core team, one for Java and one for C#.
Trained two members of the core team to perform code reviews.
Collaborated with members of the sales team to help them better understand the product's technical details, improving their communication with customers.
Performed code reviews of changes to the code generator and the auto-generated Python, Ruby, C#, and Java SDKs.

Technologies: Python, Ruby, Java, Jira, Bitbucket, GitHub, Jenkins, Slack, Team Management, Customer Support, Code Review, Code Generators, REST APIs, API Documentation, C#.NET, APIs, XML, JSON, Swagger, REST, OAuth, OAuth 2, User Authentication, JSON Web Tokens (JWT), Postman, Git, C#, .NET Core, cURL Command Line Tool, Agile, CI/CD Pipelines, Docker, Design Patterns, RESTful Development, JSON REST APIs, PyCharm, Back-end, Apache Maven, Leadership, Team Mentoring, Mentorship & Coaching, Mentorship, .NET, Python 3, Auth, SDKs, PIP, Automation, API Integration, API Design, OpenAPI, Source Code Review, Interviewing, Technical Hiring, Task Analysis, Windows PowerShell, Automation Scripting, Scripting, Software Engineering, Algorithms, Integration, RESTFul APIs, API Development, Visual Studio Code (VS Code), Visual Studio, Windows, Technical Leadership, Automations, Third-party APIs, Refactoring, Webhooks

Solutions Engineer

2018 - 2020

APIMATIC

Communicated with 120+ customers based in 20+ countries across five continents to learn about the different ways that REST APIs are being developed and used across the globe.
Delivered demos to prospective customers using Google Meet.
Designed version 3 of APIMatic’s auto-generated SDKs using customer feedback.
Assisted the support team to better understand customer issues, decreasing the average time for support ticket resolution by 50%.

Technologies: Customer Support, Product Demonstrations, APIs, JSON, Swagger, REST, OAuth, OAuth 2, User Authentication, JSON Web Tokens (JWT), JavaScript, C#.NET, Python, Java, REST APIs, API Documentation, Code Generators, Postman, Git, Jenkins, Ruby, Jira, Bitbucket, Slack, C#, cURL Command Line Tool, Agile, CI/CD Pipelines, Design Patterns, RESTful Development, JSON REST APIs, PyCharm, Back-end, Apache Maven, Team Mentoring, Mentorship & Coaching, Mentorship, .NET, Python 3, Auth, SDKs, PIP, Automation, API Integration, API Design, OpenAPI, Interviewing, Technical Hiring, Task Analysis, Windows PowerShell, Automation Scripting, Scripting, Software Engineering, Algorithms, Integration, RESTFul APIs, API Development, Visual Studio, Windows, Third-party APIs, Webhooks

Software Engineer

2017 - 2020

APIMATIC

Managed code generation of Python, Ruby, Java, and C# SDKs for REST APIs.
Tracked and fixed bugs using Jira for reporting and tracking.
Wrote changelogs for bug fixes and feature additions to keep users informed of SDK changes.
Made Python and Ruby SDKs compliant with style guides.
Updated the CI/CD cycle to add checks for Ruby and Python SDK code compliance.
Added support for OAuth 2.0 Password Grant to Ruby and Python SDKs.
Updated Java SDKs to use the OkHttp library instead of Unirest to improve performance.
Implemented a generator for the Python code samples displayed on APIMatic’s Developer Experience Portal.

Technologies: Java, C#.NET, Python, Ruby, Jira, Git, Bitbucket, Slack, Jenkins, Code Generators, REST APIs, API Documentation, Swagger, APIs, JSON, REST, OAuth, OAuth 2, User Authentication, JSON Web Tokens (JWT), JavaScript, Postman, C#, cURL Command Line Tool, Agile, CI/CD Pipelines, Design Patterns, RESTful Development, JSON REST APIs, PyCharm, Back-end, Apache Maven, .NET, Python 3, Auth, SDKs, PIP, Automation, API Integration, API Design, OpenAPI, Slack API, Windows PowerShell, Automation Scripting, Scripting, Software Engineering, Algorithms, Integration, RESTFul APIs, API Development, Eclipse, Visual Studio, Windows, Automations, Third-party APIs, Webhooks

Experience

Version 3 of APIMatic's SDKs

APIMatic has been selling SDKs since 2016 and developing them since 2014. I used the company's cumulative internal knowledge and expertise, gathered through years of customer feedback and market research, to design a new and improved version of the SDKs, which offer a far superior developer experience.

I designed the SDKs for C#, Java, Python, and Ruby and also implemented code generation for the new Python and Ruby SDKs. These SDKs are being used in production by leading companies, such as Bandwidth (https://www.bandwidth.com/) and Sabre Corporation (https://www.sabre.com/).

CI/CD Improvements for Jenkins

APIMatic uses Jenkins for its CICD cycle. On each new release, SDKs are generated, and extensive tests are performed. An increase in APIs to test had caused the pipeline to take up to an hour for a regular build.

I implemented a custom caching solution that eliminates the need to test SDKs that have not changed since the last build, resulting in the time for each build to be reduced to fifteen minutes on average, resulting in less time to delivery.

Code Sample Generator for Python

APIMatic's Developer Experience Portal is an auto-generated documentation platform for REST APIs. It includes dynamic, scalable code samples for multiple platforms, including C#, Java, and Python.

I used C# to implement a generator for the Python code samples displayed for each endpoint, generated based on the input API specification information. These work with APIMatic's Python SDKs (which can be downloaded from the same link) and make getting started with API consumption a breeze for consumers.

Education

2013 - 2017

Bachelor's Degree in Software Engineering

National University of Sciences and Technology - Islamabad, Pakistan

Skills

Libraries/APIs

REST APIs, Pandas, API Development, Auth, Amazon API, Walmart API, Slack API, Amazon Product Advertising API, OpenAPI, SQLAlchemy, Jira REST API, PySpark, Google Drive API, Google Sheets API, NumPy, Beautiful Soup 4

Tools

PyCharm, Jira, Git, Jenkins, Visual Studio, Postman, Pytest, Microsoft Excel, Google Sheets, Bitbucket, Slack, GitHub, cURL Command Line Tool, Apache Maven, Logging, Terraform, Claude Code

Languages

C#.NET, Python, C#, Python 3, Java, SQL, Ruby, Liquid Template, XML, JavaScript, HTML, CSS

Frameworks

.NET, Swagger, OAuth 2, JSON Web Tokens (JWT), .NET Core, Windows PowerShell, Flask, Unity, Unity3D, Spark, Django

Paradigms

REST, RESTful Development, Agile Software Development, Agile, Automation, ETL, Refactoring, Design Patterns, DevOps

Storage

JSON, Microsoft SQL Server, Databases, Google Cloud, PostgreSQL, MySQL, Datadog, Amazon S3 (AWS S3)

Platforms

Windows, Visual Studio Code (VS Code), Google Cloud Platform (GCP), Eclipse, Docker, Databricks, PagerDuty, Amazon Web Services (AWS), Ubuntu

Other

Algorithms, API Documentation, APIs, JSON REST APIs, SDKs, Google Cloud Functions, Google BigQuery, CSV, API Integration, API Design, Automation Scripting, Scripting, Software Engineering, Integration, RESTFul APIs, Automations, CSV File Processing, Data Structures, Team Management, Code Review, Code Generators, OAuth, User Authentication, Eve, CI/CD Pipelines, Back-end, Team Mentoring, Leadership, Mentorship & Coaching, Mentorship, PIP, Source Code Review, Interviewing, Technical Hiring, Task Analysis, Software Architecture, Software Design, Architecture, Technical Leadership, Pub/Sub, Third-party APIs, Data Extraction, Real-time Data, Webhooks, Software Development, Software Project Management, Quality Assurance (QA), Software Development Lifecycle (SDLC), Operating Systems, Customer Support, Product Demonstrations, Groovy Scripting, Serverless, Amazon RDS, Scraping, Web Scraping, Data Analysis

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