Codexworker

Custom Data Pipeline Development

I build data pipelines: extract from APIs, databases or files, transform and clean the data, and load it where you need it — usually Elasticsearch, MySQL or S3. Built to handle volume and to be observable.

I'm a backend developer with 10+ years of experience across PHP, Go, MySQL and Elasticsearch. Recent work includes Cenoskop (30M+ products daily), Niftycent (US price intelligence), and facha.sk (Go backend). I build, fix and optimize backend systems that handle real data and real traffic.

What I Can Help With

Build ETL/import/transform/export pipelines for large datasets.

Typical Problems

multiple source systems schema drift large-volume transforms incremental vs full loads observability reliable scheduling

Relevant Experience

Built ETL pipelines for Cenoskop ingesting product data from 500+ sources, transforming and normalizing it, then loading into Elasticsearch and MySQL. Handles millions of records daily with schema validation and error recovery.

What Is Included

source extraction
transformation logic
validation layer
load strategy
monitoring/retries
documentation

How It Works

We define sources/targets and SLA, build the pipeline with validation and monitoring, and run a first load. From €2,000.

Starting from €2,000

Pipeline for a primary source/target pair.

Frequently Asked Questions

How do you handle schema drift?

I version and validate schemas at the extraction boundary, and alert on drift rather than failing silently.

Related Services

Other problems I help with.

Product Data Extraction

Extract and normalize product data from external sources.

Details →

Large-Scale Web Crawler Development

Build scalable web crawling infrastructure.

Details →

Custom Price Monitoring Systems

Build price monitoring infrastructure for products/sellers.

Details →

Systems I've Built

Relevant production work.

Price Intelligence Engine

Cenoskop / Levnobot

Crawler monitoring millions of products. Processing 30M products daily and comparing them.

Built and maintain the full crawling pipeline — from scraping through Elasticsearch indexing to price comparison.

Data Aggregation Scraping ElasticSearch
US Price Intelligence

Niftycent

Price intelligence engine for the US market. Processing large-scale product data.

Built the data pipeline and crawling infrastructure for large-scale US product monitoring.

Data Aggregation Scraping Big Data
Job & Services Marketplace

facha.sk

Find a job or offer your services.

Built the Go backend — API, matching logic and deployment.

Job Marketplace Services Go
Secure Communication

Paidshield

Chat application with end-to-end encryption.

Built the backend and encryption layer for a secure chat application.

End-to-End Encryption Real-time Communication Security
Security Scanner

remotedaemon.com

Remote security scanner with ping and certificate checking.

Built the scanning daemon and monitoring backend.

Security Ping Certificate
DNS Security

Synopsee

A Cleaner, Safer Internet. Take control of your DNS. Block ads, trackers, and malicious sites with customizable profiles.

Built the DNS resolution backend and profile management system.

DNS Security Privacy
Traffic Analysis

AnalyticsForWebsite

Custom solution for collecting and evaluating traffic metrics with emphasis on processing speed and minimizing backend load.

Designed and built the backend for fast traffic metric collection and evaluation.

Performance Optimization Data Collection

Need Help With This?

Describe the problem in a few lines — I'll look at it and tell you what I think.

Discuss a data pipeline project