I'm Md Mahamudul Hasan Chowdhury, a software developer with 5+ years of hands-on experience across web development and production systems. I specialize in Ruby on Rails, Python, React, and PostgreSQL, and I have a track record of improving booking, billing, and reporting flows in live production apps, including building and optimizing APIs and improving query performance on high-traffic paths. In previous roles I supported Windows/Linux environments, access controls, and network operations. I'm known for digging into edge-case logic, fixing issues without drama, and delivering reliable software with steady, predictable delivery while keeping deployments smooth and automated. I'm always eager to collaborate with colleagues, value clean code and thorough testing, and aim to help teams deliver robust software that scales with business needs.

Md Mahamudul Hasan Chowdhury

I'm Md Mahamudul Hasan Chowdhury, a software developer with 5+ years of hands-on experience across web development and production systems. I specialize in Ruby on Rails, Python, React, and PostgreSQL, and I have a track record of improving booking, billing, and reporting flows in live production apps, including building and optimizing APIs and improving query performance on high-traffic paths. In previous roles I supported Windows/Linux environments, access controls, and network operations. I'm known for digging into edge-case logic, fixing issues without drama, and delivering reliable software with steady, predictable delivery while keeping deployments smooth and automated. I'm always eager to collaborate with colleagues, value clean code and thorough testing, and aim to help teams deliver robust software that scales with business needs.

Available to hire

I’m Md Mahamudul Hasan Chowdhury, a software developer with 5+ years of hands-on experience across web development and production systems. I specialize in Ruby on Rails, Python, React, and PostgreSQL, and I have a track record of improving booking, billing, and reporting flows in live production apps, including building and optimizing APIs and improving query performance on high-traffic paths. In previous roles I supported Windows/Linux environments, access controls, and network operations. I’m known for digging into edge-case logic, fixing issues without drama, and delivering reliable software with steady, predictable delivery while keeping deployments smooth and automated.

I’m always eager to collaborate with colleagues, value clean code and thorough testing, and aim to help teams deliver robust software that scales with business needs.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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Language

English
Fluent

Work Experience

Software Developer at Mykey Global Accommodations
October 1, 2023 - November 24, 2025
Designed and implemented a Rails-based booking payment workflow ensuring a single authoritative payment record per booking, fixing double-charge edge cases and reducing manual adjustments. Added configurable refundable-deposit rules in booking/pricing services, enforcing client settings and aligning invoices with billing policies. Refined FRV reporting with a submit-only trigger, added a submitted state, and tightened document visibility to improve audit trails and daily workflows. Expanded booking associations and enforced update-safe callbacks to prevent orphaned charges and sync issues. Optimized Active Record queries and caching to cut API latency on high-traffic paths by ~27%. Expanded RSpec integration tests around payment and booking flows to reduce flaky builds. Built GitLab CI/CD pipelines, Dockerized services, and health checks with rollback to shorten deployment windows to ~45 minutes and improve release safety.
Software Developer at Metlife
September 1, 2023 - September 1, 2023
Drove performance and reliability across Rails and React apps by refactoring slow queries, adding caching layers, and removing heavy UI assets to boost page speed by 40%. Built mechanized data-sync pipelines for ERP data into PostgreSQL and MongoDB with validation, logging, and retries to improve data accuracy by 22%. Deployed live analytics dashboards using Python and Tableau, replacing monthly spreadsheets and accelerating decision-making for finance and operations. Stabilized releases with CI checks, containerized builds, and automated tests enabling weekly production pushes without rollbacks. Strengthened payment flows with robust API handshakes, token refresh rules, and defensive logic to reduce billing failures. Mentored new engineers through code walkthroughs and pairing, sharing scalable patterns for API structure, data handling, and UI state management.
Software Developer at Metlife
July 1, 2020 - September 1, 2023
Improved page speed by 40% across key screens via query optimization, caching, and UI trimming; built mechanized data sync pipelines into PostgreSQL and MongoDB with validation, logging, and retries; introduced live analytics dashboards using Python and Tableau; stabilized releases with CI checks and automated tests enabling weekly production pushes; strengthened payment flows with reliable API handshakes and defensive logic; mentored new engineers through code walkthroughs and patterns for API structure and UI state.
Software Engineer at Mykey Global Accommodations
October 1, 2023 - Present
Designed and optimized backend automation logic for booking, billing, and reporting workflows, ensuring reliable execution, correct state transitions, and consistent data outcomes across systems. Built and maintained API-driven integrations and background workflows, handling event triggers, conditional logic, retries, and failure scenarios to support finance and operations processes. Refactored complex backend services to remove branching edge cases, improve traceability, and ensure single-source-of-truth records for automated financial workflows. Implemented configurable automation rules for pricing and deposits, validating inputs, preventing null states, and aligning automated outputs with business policies. Tuned backend queries, caching layers, and service interactions — improving automation execution performance by ~27% on high-traffic paths. Debugged and stabilized automation failures by tracing webhook payloads, API responses, and background job execution, improving system rel
Software Engineer at Metlife
July 1, 2020 - September 1, 2023
Developed and maintained backend services and data synchronization workflows integrating external systems via REST APIs and automated processing pipelines. Eliminated manual data handling by building automated backend workflows with validation, logging, and retry mechanisms, improving data accuracy by 22%. Designed reporting pipelines using Python that transformed raw system data into analytics-ready outputs for business teams. Improved application reliability by introducing automated tests, CI validation, and containerized builds for backend services. Strengthened backend integrations through consistent API contracts, defensive request handling, token refresh logic, and error monitoring. Worked independently on complex backend tasks while coordinating remotely with cross-functional teams to deliver stable releases.
Backend Software Engineer at Mykey Global Accommodations
October 1, 2023 - Present
Led backend development of booking and payment processing systems, ensuring transactional integrity and eliminating duplicate charge scenarios across production workflows. Designed and implemented RESTful APIs to support billing, deposit rules, and financial adjustments. Enforced strict data validation and state management rules to prevent inconsistent financial writes and ensure invoice accuracy. Integrated third-party billing and payment providers with defensive request handling, token validation, retry logic, and logging to reduce transaction failures. Optimized PostgreSQL queries and indexing strategies across high-volume payment endpoints, improving API response performance by ~27%. Expanded integration and API test coverage, reducing production payment defects by ~30% and increasing deployment confidence. Built Dockerized deployments and CI/CD pipelines with rollback support, improving release safety and reducing downtime.

Education

Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic
May 1, 2022 - February 6, 2026
Master of Science in Physics at University of Saskatchewan
March 1, 2014 - February 6, 2026
Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic, Canada
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan, Canada
January 11, 2030 - March 1, 2014
Diploma in Computer System Technology at Saskatchewan Polytechnic
January 11, 2030 - May 1, 2022
Master of Science in Physics at University of Saskatchewan
January 11, 2030 - March 1, 2014

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Computers & Electronics, Professional Services, Financial Services, Education, Other