Senior Java Developer · Monetech
03.2026 – 09.2026 · 7 mos
monetech.mx · Remote, Warsaw, Poland
Company exited the Mexican market; the entire team was laid off.
Achievements
- Built a greenfield BNPL (Buy Now, Pay Later) platform from scratch to production in 3.5 months.
- Designed the Conekta payment layer: card vaulting, 3DS, idempotent orders, signed webhooks.
- Built auto-debit scheduling aligned to paydays, with decline-aware retry logic. Fixing the retry window bug and classifying issuer declines raised the auto-debit success rate by ~15%.
- Automated PDF generation of 5 types of regulatory loan documents, including re-issue after partial refunds. Removed 100% of manual document preparation.
- Resolved 4 production incidents, including one that blocked 12 customers from paying. Average time to fix: under 1 business day.
- Worked spec-first (OpenSpec): 23 formal specs, 104 merged MRs, 37 DB migrations, ~90 Jira tickets.
- Integrated 5 external providers (Conekta, STP, Inbursa, Prelude, Resend).
Projects
- BNPL Platform. Checkout financing for online stores: OTP, KYC, credit bureau scoring, e-signed contracts, loan disbursement, installment schedules, auto-debit, prepayments, refunds, cashback, customer portal and backoffice.
Stack
- Kotlin
- Java 21
- Spring Boot 3
- PostgreSQL
- Liquibase
- Claude Code
- TypeSpec/OpenAPI
- Testcontainers
- WireMock
- Kubernetes
- GitLab CI
Senior Java Developer · IT grows
10.2022 – 02.2026 · 3 yrs 5 mos
itgrows.today · Remote, Warsaw, Poland | Belgrade, Serbia
Achievements
- Built 5 production microservices from scratch and owned them for 3+ years: payments, fiscal journal, billing, API gateway, hotel fiscalization. Main contributor across 8 repositories, 900+ commits.
- Designed a SoftPOS (Tap-to-Phone) payments backend: onboarding, purchases and refunds, retries, reconciliation.
- Decomposed a legacy monolith using the Strangler Fig pattern: built a gateway with DB-driven, API-version-aware routing and migrated ~30 of 48 routes.
- Modernized a 10-year-old platform and removed 100k+ lines of dead code. Released 14 API versions.
Projects
- POS Backend. Cloud backend for mobile cash registers: receipts, reports, fiscalization via certified control units (PosPlus, CleanCash, CCU), Swedish Tax Agency compliance.
- SoftPOS Payments. Tap-to-Phone card acceptance on Android devices.
- Billing & Fiscal Journal. Monthly PDF invoice specifications for software vendors, based on receipt fiscal data.
- Sea Freight Platform. Cost and CO₂ calculator for multimodal shipping (NestJS/TypeScript).
Stack
- Java
- Kotlin
- Spring
- Hibernate
- TypeScript
- Node.js
- React
- Kubernetes
- RabbitMQ
- PostgreSQL
- Testcontainers
- gRPC
- Prometheus
Technical Lead, Senior Java Developer · Domclick
04.2019 – 07.2022 · 3 yrs 4 mos
domclick.ru · Moscow, Russia
Achievements
- Developed payment microservices: one for payment processing and another for receiving refund requests, which increased the bank's profit from sales contracts.
- The services were used as platform services by 10+ product teams.
- Became the Tech Lead of a development team of 4 software engineers.
- Built the business process for digital mortgage registration in the state registry on a microservice architecture. Cut registration time from days to hours for thousands of mortgages per month.
Projects
- Digital Mortgage Registration. Services maintaining the business process for electronically registering a mortgage document in the official registry.
- United Front System. Management system for Mortgage Loan Officers in the bank.
Stack
- Java
- Kotlin
- Spring
- Spring Cloud
- Hibernate
- Kubernetes
- RabbitMQ
- Microservices
- ELK stack
- PostgreSQL
- SonarQube
- Testcontainers
- Grafana