| Sanaz Safaei - Senior Software Engineer | PHP, AWS, Kubernetes Expert |
Experience
Senior Software Engineer
Nov 2023 — Present (1 Year and 9 months)
Digikala is an integrated ecosystem of online businesses, including B2C and B2B operations. It offers a robust B2C platform with over
41 million active users and more than 9.7 million products.
- Scalable Subscription Service: Designed and developed a Service-Oriented Architecture (SOA) system for 150,000 daily users, collaborating closely with the Subscription Team and providing technical direction.
- Enhanced System Monitoring: Developed a Kubernetes cluster with Kubeadm, aggregating data, and unifying Prometheus, InfluxDB, and Elasticsearch into a single Grafana dashboard.
- Established Automated Testing: Took the initiative to establish unit and integration testing within the team, achieving over 50%+ test coverage across all Order Management system sections and automating tests in the GitLab pipeline.
- Initiated new product type in checkout flow: Architected the checkout flow to support selling services alongside products, making installation services feasible through third-party integration.
- Mentored & Onboarded Engineers: Assisted in hiring, onboarding, and mentoring 7 new engineers, leading technical discussions and improving project onboarding efficiency.
Software Engineer
Oct 2021 — Oct 2023 (2 Years)
- Optimized High-Traffic Systems: Optimized Legacy Systems by reducing API response times by 12% using Memcache, ensuring seamless performance for APIs handling 4,000-5,000 requests per second under high load.
- Improved Payment Reliability: Designed a fault-tolerant system to handle IPG delays and failures, ensuring successful recovery of 1,000+ incomplete transactions monthly.
- Reduced Data Redundancy: Eliminated 600+ duplicate daily entries, preventing system conflicts and optimizing MySQL database efficiency.
- Built a Custom Voucher System: Developed a seller panel feature supporting 45+ configurable conditions, generating an average of 35,000 targeted vouchers per promotion.
- Launched New Shipping & Promotions Features: Introduced enhancements to delivery services, driving an increase of 30,000 monthly orders.
Back End Developer
Jan 2021 — Oct 2021 (9 Months)
- Developed a Payment System: Built a FastAPI-based payment application with RESTful APIs and financial integrations.
- Integrated QR Code Authentication: Reduced login time from 1 minute to under 30 seconds by implementing Redis caching and Pub/Sub with Aioredis, significantly cutting OTP costs.
- Real-Time Notifications: Engineered a WebSockets-based notification system for 6 out of 11 key app flows, improving user engagement and responsiveness.
- Designed and Implemented Database Solutions: Using SQLAlchemy and Gino, with Alembic for migrations, including the use of schedulers and interval functions for updating cached data.
Back End Developer Intern
Jul 2020 — Dec 2020 (6 Months)
- Built a Comprehensive Clock-In System: Developed from scratch using the Django framework in Python3.
- Managed Legacy Code: Maintained forms and databases using Python2 and Django framework.
- Integrated Databases: Worked with PostgreSQL and SQLAlchemy for various client-specific projects.
Education
Bachelor of Science in Computer Engineering
Sep 2015 – Sep 2020 (5 Years)
One of Iran's top 5 universities, renowned for its rigorous engineering programs and cutting-edge research in computer science and technology.
Publications & Projects
🔗Hermes: Scalable and Robust Structure-Aware Optimal Routing for Decentralized Exchanges
I was honored to develop experiences with a parameterized algorithm that leverages the low treewidth of DEX transaction graphs.
The algorithm achieves superior time complexity compared to existing methods while providing formal optimality guarantees. Using real Uniswap data from 20,000 blocks,
we implemented this in the open-source tool Hermes and conducted large-scale experiments. Hermes outperformed existing methods by over four orders of magnitude on small instances
(2.81s → 0.0002s) and was the only tool capable of handling 100,000 tokens, achieving an average runtime of 0.19s.
Authors: S. Farokhnia, S. Novozhilov, S. Safaei, J. Shen
Technologies: DeFi, Python, Pandas, GraphQL
Conference: IEEE International Conference on Blockchain, Blockchain'25
Certifications
- IELTS Academic (Overall Band Score: 7.0) - September 2025
- Fundamentals AWS Cloud Technical Essentials - February 2024