FinTech and trading systems
Real-time market data, MT4/MT5 integrations, synchronized gRPC streams, SignalR, WebSockets, account and trading workflows, Kafka, Redis, failover, and production observability.
Senior .NET Backend Engineer | FinTech & Distributed Systems | Mexico City / Remote
Eugenia Tamasyan
I turn complex backend products into systems that are faster, safer, and easier to scale
10+years delivering production software
30%higher backend performance
50%lower application resource use
75%faster order processing
Best fit
Engineering the systems your product depends on
Bring me the system that is already valuable but slow to change, expensive to operate, difficult to debug, risky to migrate, or under pressure to scale. I connect business flow, code, data, integrations, infrastructure, and observability into one practical delivery plan.
Senior engineering range
Senior backend ownership from system design to measurable production outcomes
I work across architecture, hands-on implementation, performance, integration reliability, delivery planning, and the production feedback loop that keeps a valuable product dependable.
Architecture and modernization
DDD, CQRS, Event Sourcing, Clean Architecture, modular monoliths and microservices, Saga and Outbox patterns, API contracts, legacy modernization, and cloud-ready service boundaries.
Performance and reliability
C# profiling, SQL execution plans, distributed query optimization, resource analysis, caching, logging, Toxiproxy fault testing, health checks, and root-cause investigation.
Technical leadership
Discovery, requirements, architecture trade-offs, estimates, task decomposition, code reviews, mentoring, incident communication, delivery planning, and alignment with product and infrastructure teams.
Selected product work
Products built for real operational pressure
A selection of platforms and business domains I have contributed to through backend engineering, architecture, modernization, team leadership, or product implementation.
FinTech / Forex / Distributed Systems
High-performance trading platform
Product: A multi-market trading ecosystem with account operations, market data, trading tools, analytics, economic events, and mobile experiences.
Contribution: Backend services in C#/.NET, MT4 data retrieval, event subscription lifecycles, synchronized gRPC streams, REST integrations, Kafka, Kubernetes, Elasticsearch, and production troubleshooting.
30% faster core logic and 23% lower backend processing time.
C#.NETASP.NET CoreRESTgRPC streamingSignalRWebSocketsDDDCQRSEvent SourcingMT4 / MT5KafkaRedisMySQLMongoDBElasticsearchAWSDockerKubernetesArgoCDPrometheusGrafanaKibanaToxiproxy
Digital Assets / Payments
FinTech wallet and card experience
Product: A consumer finance product combining digital-asset balances, yield, cashback, global card spending, and mobile-first money movement.
Contribution: Product and integration thinking for secure account flows, balance operations, API-driven experiences, failure handling, and observable transaction workflows.
A clear, mobile-first product flow designed around trust and operational visibility.
C#.NETFinTech APIsRESTgRPCSignalRWebSocketsDDDCQRSEvent SourcingOutbox PatternKafkaRedisPostgreSQLWebhooksOAuth / OIDCSecurityDockerKubernetesOpenTelemetryObservability
SaaS / Device Management
Smartphone management SaaS
Product: A platform for payment reminders, device policy enforcement, customer communication, marketing widgets, and remote smartphone management.
Contribution: Backend development and team leadership across .NET 6 microservices, RabbitMQ workflows, relational databases, Hangfire jobs, integration stabilization, planning, and mentoring.
20% improvement in system stability across microservice integrations.
C#.NET 6ASP.NET CoreRESTSignalRWebSocketsDDDCQRSSaga PatternOutbox PatternRabbitMQMassTransitPostgreSQLMySQLMariaDBEntity FrameworkHangfireDockerAWSJenkinsPrometheusGrafanaReactGitLab
Enterprise Retail / Data Processing
Retail logistics and forecasting
Product: Business-critical systems for store ordering, goods distribution, inventory forecasting, perishable-product loss prevention, reporting, and ETL.
Contribution: Progressed from engineer and business analyst to Team Lead, designing calculation algorithms, SQL-heavy data workflows, reporting logic, and operational automation.
75% faster order calculations and 30% more reporting capability.
C#.NET FrameworkASP.NETSQL ServerTeradataADO.NETT-SQLETLWCFWPFWindows ServicesReportingData Warehousing
Blockchain / Product Engineering
Crypto mining pool product
Product: A mining-pool experience with balances, payouts, profitability reporting, fiat conversion, device monitoring, and customer support workflows.
Contribution: Product-oriented architecture and implementation work around financial data presentation, API workflows, reliability, responsive interfaces, and operational transparency.
Complex operational data translated into a clear customer-facing product.
C#.NETBlockchain APIsRESTgRPCSignalRWebSocketsEvent SourcingWebhooksFinancial DataSQLBackground JobsPayout WorkflowsMonitoringResponsive UI
AI Product / Web Platform
AI casting platform
Product: An AI-assisted casting concept for structured talent data, intelligent candidate matching, profile discovery, production partnerships, and workflow automation.
Contribution: Product packaging, responsive website implementation, service positioning, structured feature presentation, and AI-enabled workflow design.
A complex AI product translated into an understandable, conversion-focused experience.
AI WorkflowsLLM APIsStructured DataNext.jsReactTypeScriptResponsive UISEOProduct UXVercel-ready delivery
Consulting and delivery
Start with clarity and scale into implementation
Low-friction consultations help define the real problem before budget is committed. Fixed-price implementation is available for bounded, testable scopes.
From $40
.NET architecture consultation
30 min / 1 day summary
A focused review of architecture, service boundaries, stack choices, scalability risks, cloud direction, data and messaging options, or a modernization decision.
- Live technical session
- Written recommendations
- Risks and trade-offs
- Prioritized next steps
From $40
FinTech and trading consultation
30 min / 1 day summary
Architecture guidance for market data, MT4/MT5 integrations, real-time prices, Kafka/Redis responsibilities, WebSockets, wallets, failover, latency, and reconciliation.
- High-level data flow
- Reliability risks
- Latency review
- Implementation priorities
From $350
.NET codebase and architecture audit
3 business days
A senior review of one repository or service, focused on the problems that affect delivery speed, reliability, security, performance, and maintainability.
- Severity-based findings
- Technical-debt priorities
- Business impact
- Practical roadmap
From $550
Performance and SQL optimization
4 business days
Profiling and targeted optimization for a bounded API workflow, background process, database operation, or distributed data path.
- Baseline and bottlenecks
- Code or query changes
- Before/after comparison
- Monitoring advice
From $250
Production bug diagnosis and fix
2 business days
Root-cause investigation for reproducible C#/.NET defects, API failures, SQL issues, race conditions, background jobs, serialization, integrations, and production-only behavior.
- Root-cause analysis
- Source-code correction
- Validation
- Regression protection
From $450
API, AI, or business integration
4 business days
Reliable integration of an AI provider, email platform, CRM, Shopify, payment provider, document service, webhook, or another third-party API into a .NET product.
- Authentication and mapping
- Retries and errors
- Structured logging
- Setup documentation
Prices are starting points for the defined scope. Larger systems, multiple services, production access, or custom integrations are estimated after discovery.
Professional experience
Career evidence with product context
The role matters, but the product, operational constraints, and measurable result matter more.
Dec 2022 - Present
Software Engineer
ZFX / Traze / Zeal Group
A multi-brand fintech ecosystem spanning the ZFX brokerage platform, Traze web and mobile trading experiences, and Zeal digital-finance products. The product landscape includes market data, account and trading operations, economic content, analytics, integration services, and always-on production infrastructure.
- Build and optimize C#/.NET backend services used by broker-facing and customer-facing product flows across ZFX, Traze, and the wider Zeal product ecosystem.
- Work with REST and synchronized gRPC streams, Kafka, MySQL, MongoDB, Elasticsearch, Redis, AWS, Docker, Kubernetes, ArgoCD, and GitLab delivery pipelines.
- Designed MT4 data-retrieval logic with controlled event subscription/unsubscription, synchronized streaming, and safer lifecycle handling for real-time backend processing.
- Improved searchable production diagnostics through Elasticsearch, Prometheus, Grafana, and Kibana, and validated service behavior under dependency failures with Toxiproxy.
- Investigate production incidents and business-critical trading logic together with QA, infrastructure, product, and operational stakeholders.
Impact: 30% performance improvement, 23% faster backend processing, and more reliable failover validation.
May 2022 - Dec 2022
Senior Software Engineer
IBS / SUEK (Remote)
Enterprise modernization for SUEK: APIs, document-recognition pipelines, file-processing services, SAP-connected workflows, and ECM ingestion used inside a large industrial organization.
- Extracted legacy business logic into modern .NET 5/6 APIs and cross-platform services without interrupting established enterprise workflows.
- Worked on document recognition, file conversion, metadata processing, ECM ingestion, and integration paths connecting internal systems with SAP-related dependencies.
- Led Docker migration for platform-specific components including SAP, System.Drawing, and document-processing libraries, resolving Linux compatibility constraints.
- Coordinated CI/CD pipelines, environment partitioning, Kubernetes deployments, resource allocation, and release readiness with infrastructure engineers.
Impact: Reduced application resource consumption by 50% and lowered modernization risk through phased migration.
Jun 2021 - May 2022
Senior Software Engineer / Team Lead
7tech
A smartphone-management SaaS platform for payment collection, device policies, remote actions, customer communication, and marketing workflows.
- Delivered .NET 6 microservices with RabbitMQ, PostgreSQL/MySQL/MariaDB, Entity Framework, Hangfire, Docker, AWS, and Jenkins.
- Led refinement, estimates, task decomposition, delivery priorities, quality control, and integration stabilization.
- Mentored engineers through reviews, one-to-ones, technical guidance, and individual growth planning.
Impact: Improved system reliability by 20% while strengthening team delivery and product stability.
Sep 2020 - Jun 2021
Senior Software Engineer
Renaissance Insurance
Business-critical insurance workflows and supporting APIs with complex rules, integrations, and regression-sensitive behavior.
- Refined C#/.NET Core business logic, SQL Server data access, REST services, Docker workflows, Serilog/Seq diagnostics, and TeamCity delivery.
- Expanded NUnit/Moq unit and integration coverage around high-risk functionality and supported cross-team code reviews.
Impact: Improved performance by 7% and reduced regression risk through stronger automated coverage.
Feb 2020 - Sep 2020
Software Engineer
Renault Russia
An internal enterprise portal connecting business users, backend workflows, data, and operational services.
- Developed backend and frontend components with .NET Core/.NET Framework, ASP.NET MVC/Web API, Angular, SQL Server, and Docker.
- Translated stakeholder requirements into delivery-ready work and contributed to architecture and cloud migration planning.
Impact: Improved distributed query execution by 43% and helped reduce operational costs by 10%.
Aug 2014 - Feb 2020
Team Lead / Senior Software Engineer
MAGNIT
Large-scale retail ordering, logistics, distribution, forecasting, reporting, ETL, and perishable-loss-prevention systems.
- Designed C# and SQL-heavy algorithms for store ordering, goods allocation, inventory forecasting, and operational reporting.
- Led prioritization, task distribution, technical guidance, employee development, and hands-on delivery of critical work.
- Automated reporting and raw-data uploads to reduce manual work and improve data integrity.
Impact: Reduced order-processing time by 75% and increased reporting capability by 30%.
Technology depth
A broad stack organized around outcomes
Tools are useful when they support the right architecture, operating model, and business constraints. This is the range I can bring into that decision.
Backend and APIs
C#.NET / .NET CoreASP.NET CoreWeb APIMinimal APIsRESTgRPCgRPC streamingGraphQLSignalRWebSocketsMediatRMassTransitHangfireAsync / AwaitLINQNode.jsGoPython
Architecture and integration
Domain-Driven DesignDDDCQRSEvent SourcingClean ArchitectureHexagonal ArchitectureMicroservicesModular monolithDistributed systemsEvent-driven architectureSaga PatternOutbox PatternIdempotencyEventual ConsistencyCircuit BreakerAPI GatewayAPI designLegacy modernizationKafkaRabbitMQMT4 / MT5SAPECMWebhooks
Cloud and platform
AWSAzureYandex CloudDockerKubernetesHelmTerraformArgoCDFluxGitOpsGitLab CI/CDGitHub ActionsAzure DevOpsJenkinsTeamCityBambooHarborNexusArtifactory
Data and persistence
SQL ServerPostgreSQLMySQLMariaDBOracleTeradataMongoDBRedisElasticsearchEntity Framework CoreDapperADO.NETSQL tuningExecution plansCachingDistributed locks
Quality and observability
OpenTelemetryPrometheusGrafanaKibanaApplication InsightsJaegerSerilogNLogSeqZipkinHealth ChecksxUnitNUnitMSTestMoqTDDIntegration testingContract testingToxiproxyFault-tolerance testing
AI-assisted engineering
Claude CodeOpenAI CodexGeminiOpenAI APIAI integration designPrompt-assisted developmentCode reviewTest generationTechnical researchDocumentation workflows
About me in person
Calm ownership, direct communication, and genuine curiosity about the product
I am a Senior .NET Backend Engineer based in Mexico City, working comfortably with international and distributed teams.
I like understanding why a system exists before deciding how to change it: learning the business flow, listening to the people who operate the product, and making technical trade-offs visible without hiding them behind jargon.
Colleagues can expect a hands-on partner who stays composed around production problems, communicates progress clearly, reviews code with context, and helps other engineers become more independent. I am especially energized by fintech, trading infrastructure, data-intensive platforms, modernization, and practical AI-assisted engineering.
Mexico City; remote worldwide
10+ years in production systems
Engineering mentor and reviewer
English and Russian
Available for senior roles and consulting
Let's make the hard system understandable again
Senior .NET Backend Engineer, FinTech Engineer, Platform Engineer, Technical Lead, architecture consultant, or a focused partner for a critical technical problem.