Alexander Sokolov

Financial Systems Engineer · CFO background
Management accounting systems for fintech and e‑commerce: ledgers, reconciliation, balance sheet, P&L and cash flow reporting
Remote · UTC+7 · Full-time or contract

alsok@alsok.org · Telegram · GitHub · LinkedIn

Double-entry ledger engine, built from scratch, in production
AI agents in production, OpenAI, Claude, Gemini
Python, Django and FastAPI in production since 2021

Profile

Financial systems engineer: I design and build ledgers, reconciliation and financial reporting for fintech and e-commerce on Python (Django, FastAPI) and PostgreSQL. I combine backend engineering with hands-on accounting knowledge: I design the chart of accounts, period close and reporting myself, having set up management accounting as a CFO. In a financial system I care most about correctness, a traceable trail for every entry, and protection against double posting. I work with LLM APIs: OpenAI (since its early releases), Claude, Gemini; today, building AI agents for production.

Key Competencies

Double-entry ledger engines as the system of record: chart of accounts, period close, balance invariants.
Reconciliation of Shopify Payouts, Stripe and Amazon payouts against the ledger, to the cent.
Correctness and audit: idempotent processing of operations and webhooks, no double posting, a traceable trail for every entry.
Multi-currency: FX accounting with rate fixing, Realized FX Gain/Loss.
Financial reporting from the ledger: balance sheet, P&L and cash flow, by department and consolidated.

Experience

Fintech company (NDA) · Financial Systems Engineer · Dec 2025 - present

Production financial system. Company name withheld under NDA. Python, Django, PostgreSQL.

Built a double-entry ledger engine from scratch (Account, LedgerEntry, Operation, Period): debit/credit equality, zeroing of clearing accounts.
FX, cash and affiliate accounting with rate fixing and Realized FX Gain/Loss; balance sheet, P&L and cash flow reports by department and branch, and consolidated.
AI in production: a Grafana log agent via MCP (read-only) turns incidents into engineer tickets; MCP access to CRM and ledger databases over SSH for diagnostics.

VitalityNode · Financial Systems Engineer · May 2025 - present

E-commerce products and client projects. Django, Django-Ninja, PostgreSQL, Redis.

Pet Connector, a freemium Shopify app: Shopify Billing API, 7 Smart Fields with self-restoring metafields, Klaviyo, GDPR webhooks.
GMC Scanner (Risk Radar): risk analysis of Google Merchant Center feeds and Google Product Taxonomy category matching.
AI Shopify app: product titles, descriptions, tags and categories from product photos via OpenAI API. Was published on the Shopify App Store, now closed.

Yesim (contract) · Backend Laravel Developer · Jun 2026 - Sep 2026

B2B2C Shopify app for eSIM resale. PHP 8.2, Laravel 12, MySQL, Redis.

Merchant markup (fixed and percentage), revenue split between the eSIM supplier and the merchant.
Catalog sync of thousands of eSIM plans into Shopify products via metafields and bulk uploads.
Idempotent orders/paid webhook: eSIM activation and QR code emailed to the buyer.

Brif · Backend FastAPI Developer · Aug 2024 - May 2025

FastAPI backend for weather data (NetCDF, BUFR): multidimensional vectorized computation on NumPy and xarray.

InterPress IH · Backend Django Developer · Dec 2021 - Aug 2024

Production Django system: DRF REST API, integrations, middleware, Swagger.

Auroville Earth Institute · Full-Stack Django Developer · Feb 2021 - Dec 2021

Django information system, 30+ years of data migrated from Excel to PostgreSQL.

Mother’s flowers · Python Developer · Jan 2019 - Dec 2020

Data collection, cleaning and structuring on Python and MySQL.

Earlier. First Deputy CEO of CIEL, a manufacturing and distribution holding (finance, marketing, IT): management accounting from scratch, a cost model for hundreds of SKUs and thousands of components, ERP rollout (1C) and specifying work for developers. Before that, senior roles in banking and investment companies.

Skills

Backend: Python · Django · FastAPI · Celery · PHP 8.2 · Laravel 12 · PostgreSQL · MySQL · Redis · Docker
Integrations, data, AI: REST API · GraphQL · Shopify Admin API · Pandas · OpenAI · Claude · Gemini · MCP
Finance: management accounting, budgeting, COGS · 1C · Odoo · NetSuite · QuickBooks
Languages: Russian (native), English (technical reading and writing, async communication)

Education

Lomonosov Moscow State University, Mathematical Methods in Economics · Managerial Accounting Diploma, ICFM (UK)