// cv.sergiuscraft.com

I build things
that last.

Full-stack developer specialising in finance integrations, EDI pipelines, and backend automation. Python, Perl, PHP, vanilla JS. Code that ships clean and runs quietly.

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Stack
MacOSArch LinuxFinancial ReportingMongoDBPostgresMySQLRest APIsPythonPerlWorkflowsEmail & Print AutomationZUGFeRDVentya (Accelya)UBL 2.1SvefakturaSendysSAF-T PLOIOUBLEDICOME-InvoicingDunning LettersE-mailSMTP RelayOAuthSFTPLinuxBashHTML/CSSVanilla JSDjangoReactAR / APComplianceAudit TrailsGit / SVNDockerMacOSArch LinuxFinancial ReportingMongoDBPostgresMySQLRest APIsPythonPerlWorkflowsEmail & Print AutomationZUGFeRDVentya (Accelya)UBL 2.1SvefakturaSendysSAF-T PLOIOUBLEDICOME-InvoicingDunning LettersE-mailSMTP RelayOAuthSFTPLinuxBashHTML/CSSVanilla JSDjangoReactAR / APComplianceAudit TrailsGit / SVNDocker

// expertise

What I actually do

EDI and E-Invoicing
Finance Integration

Production experience with EDICOM, OIOUBL, SAF-T, Sendys, Svefaktura, UBL 2.1 and others. Built parsers, validators, and delivery pipelines for EU e-invoicing mandates across multiple countries.

EDICOMOIOUBLSAF-T PLSendysSvefakturaUBL 2.1Ventya (Accelya)ZUGFeRDE-Invoicing
Dunning Automation
Accounts Receivable

Designed and built end-to-end dunning email systems — escalation logic, template engines, scheduling, and audit trails. Finance-domain thinking baked in from day one.

Email & Print AutomationWorkflowsDunning Letters
Backend & Automation
System Engineering

High-throughput pipelines, cron-driven processors, SFTP/OAuth integrations — the unglamorous infrastructure that keeps financial systems of one of the world's largest Travel & Transportation companies running at scale.

PerlPythonE-mailSMTP RelayOAuthSFTPLinuxBash
Web Development
Frontend + Backend

Full-stack Python/Rest API. No framework religion — just clean, maintainable code that renders fast and doesn't require a build system to change a button label.

PythonRest APIsMySQLPostgresMongoDBHTML/CSSVanilla JSDjangoReact
Finance Domain
Business Logic

MSc in Enterprise Financial Controlling + years in financial services. I understand the business logic behind the code — AR, AP, audit trails, reporting, and compliance aren't just requirements, they're context.

Financial ReportingAR / APComplianceAudit Trails
DevOps & Tooling
Infrastructure

Linux-first developer. Arch Linux / Open Suse + MacOS daily. Git, SVN, custom deploy scripts, monitoring hooks. Comfortable owning the full stack from OS up — not just handing off to someone else's pipeline.

Arch LinuxMacOSBashGit / SVNDocker

// experience

2018–now
Full-Stack Developer
Consultancy Services Company · UK
Built and maintained EDI pipelines, dunning automation, OAuth/SFTP integrations, invoices and financial reporting tools. Perl + Python backend. PHP, HTML, CSS, vanilla JS. MySQL, Postgres, Firebird.
2017
Manual QA
Tech Sector · USA
Test automation, process documentation. Built an early instinct for reliability and edge-case thinking.
Education
MSc — Enterprise Financial Controlling
University · Ukraine
Finance, accounting, audit, and business analytics. The reason I actually understand the systems I build for.

// selected work

Projects

A-01

EDI Delivery System

Multi-format e-invoice generation and delivery across UBL, OIOUBL, Svefaktura, SAF-T PL, EDICOM, and Sendys. Handles country-specific validation, retry logic, and audit logging.

SAF-TUBLPerlXMLTemplates
A-02

Dunning Engine

Automated accounts receivable dunning — escalation sequences, dynamic templates, scheduling, and full audit trail. Reduced manual AR workload significantly.

Email AutomationMySQLPythonPerlXMLJSON
A-03

OAuth Layer

Secure data exchange layer connecting internal systems with external finance partners via OAuth 2.0. Handles token refresh, retry queues, and delivery confirmation.

OAuth 2.0PerlPythonLinux
A-04

Financial Audit & Reporting Platform

Internal reporting dashboard and audit summary tooling for a financial services company. Aggregates transactional data, generates period reports, and maintains a tamper-evident audit trail. Zero framework dependencies, runs fast on modest hardware.

ReportingAuditMySQLPDF::API2

// about

The engineer

Code as craft. Finance as context. No overengineering, no framework soup.

I'm Sergey — a developer based in Ukraine, with 8+ years shipping production code in financial services. My background is unusual: an MSc in Enterprise Financial Controlling landed me in tech, so I actually understand the business logic behind the systems I build.

My main arena is backend — Python, Perl, PHP, JS — with a heavy focus on finance integrations: EDI formats, dunning pipelines, SFTP transfers and OAuth handshakes. The kind of plumbing that has to work silently at 4 a.m.

Experience 8+ years
Speciality Finance Integrations
EDI Formats EDICOM · OIOUBL · SAF-T · SENDYS · SVEFAK · UBL
Location UA
Setup Linux, MacOS, Windows
Status Limited remote

// contact

Let's build
it solid.

Considering remote contracts, consulting, and interesting problems. Response guaranteed.