John Mark

John Mark Python Backend Developer | Data Pipeline | Web Crawling | Dashboard & ETL Currently in Asia (Available for Remote Work) Ready to start immediately Email:- Job Objective Position: Python Backend Developer / Data Engineer / Data Analyst Availability: Immediately Preferred Projects: Short-term freelance, MVP builds, automation/data pipelines Expected Rate: Negotiable Technical Skills Languages & Frameworks: Python, Django, FastAPI, Flask, Sanic Data/ML: Pandas, Polars, NumPy, ARMA, PyTorch (basic), Sklearn, Clickhouse Big Data: HDFS, Hive, Spark, Azkaban, Sqoop Scraping/Automation: Playwright, Scrapy, Tesseract OCR, OpenCV, aiohttp Databases: MySQL, PostgreSQL, Redis,MongoDB Visualization: matplotlib, Redash, Echarts DevOps & Infra: Docker, Linux, Nginx, Celery Frontend: Vue 3, Axios, JS Other Tools: JWT, Elasticsearch (basic), Kafka (basic) Work Experience Freelance Remote Projects Python Backend Engineer / Data Analyst Mar 2023 – Present Developed ERP modules (inventory, procurement, finance) and admin dashboards Implemented pandas-based financial and supply KPIs with ARMA forecasts Built polars-based data cleaning pipelines and PyTorch recommendation microservices Designed FastAPI + playwright crawlers with anti-bot and image OCR handling Independently developed a full-stack novel download website with Django REST API and Vue 3 frontend Designed responsive UI using Vue 3 + Pinia + Element Plus; implemented secure login, coin-based download access, leaderboard, and point history BlueFocus Data Technology Python Backend Developer & Data Analyst Jul 2019 – Dec 2022 Designed business middleware platform (Django + DRF), with Excel/PDF generation, Redis cache Developed aiohttp microservices to auto-fetch and ETL multi-platform ad data Built Spark + Hive data warehouse and dashboards with Redash Generated sales/finance reports and visual KPIs with pandas, numpy, matplotlib Yuanshi Cloud Technology Python Developer Nov 2016 – Apr 2019 Developed e-commerce platform modules (shopping cart, order, inventory) Built static homepage generator with Celery and Solr-based product search Applied optimistic locking, Redis cache, and transaction isolation on order service Featured Projects ERP Dashboard & Forecasting Microservices -) FastAPI + pandas for procurement/sales/finance KPIs Time series forecasting via ARMA, charted with matplotlib Dashboard delivered to mobile + web using REST API Recommendation System (ETL + ML) (2024) Cleaned large user behavior datasets with polars Built and trained basic recommendation model using PyTorch Anti-Captcha Web Crawling & Scraping System -) Automated multi-source data scraping with playwright + Tesseract OCR Implemented captcha-solving, table extraction, and async pipelines with FastAPI Big Data Platform for Ad Analytics -) Scheduled ETL of 700GB+ daily ad data with Azkaban + Sqoop Computed cost and conversion metrics using Spark SQL, delivered via Redash CRM System with Asynchronous Microservices -) Django + Thrift for internal business platforms Implemented billing/invoicing services with async PDF generation and email delivery Education Tianjin University, B.Sc. China · 2013 – 2018 Strengths & Work Style Strong at remote collaboration, async communication, and documentation Capable of full-cycle project delivery: scraping → cleaning → modeling → dashboard Experienced with both team roles and end-to-end freelance delivery Portfolio, sample code, and references available upon request.