Adam Nowak

Senior Software Engineer

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Warsaw, Poland

Experience

Jul 2021 - Dec 2025
4 years 6 months

Senior Software Engineer

Polarising

  • Owned delivery of a multi-tenant SaaS product with React and Next.js (SSR/ISR), standardizing data access patterns through GraphQL (Apollo) and improving UI consistency across modules.
  • Designed service boundaries and migrated monolithic workflows into containerized microservices using Python (Django/Flask), Node.js, Java (Spring Boot), and .NET Core to enable independent scaling and safer releases.
  • Implemented event-driven processing with Kafka and RabbitMQ for ingestion, notifications, and long-running jobs, using idempotency keys, retries, and DLQ patterns to ensure reliability under load.
  • Built applied AI capabilities (LLM/NLP) including summarization, classification, and semantic search; implemented RAG pipelines with embeddings and vector indexing using LangChain to improve knowledge discovery.
  • Created secure REST and GraphQL APIs with strict validation, pagination, rate-limiting, and consistent error contracts; reduced client over-fetching and improved perceived performance.
  • Developed a React Native mobile app for operational workflows, integrating Firebase authentication, push notifications, and offline-first synchronization to support field usage.
  • Implemented subscription billing with Stripe/Braintree, validating webhooks, handling proration and refunds, and maintaining clear reconciliation trails for finance operations.
  • Deployed services on AWS EKS using Docker and Kubernetes, standardizing environments and improving horizontal scalability; leveraged S3 for documents and CloudFront for edge delivery.
  • Improved p95 API latency through PostgreSQL indexing/query tuning and Redis caching; optimized MongoDB aggregation pipelines and reduced hot-path queries via targeted denormalization.
  • Built CI/CD pipelines with GitHub Actions and CodePipeline including automated testing, dependency scanning, and rollout gates; adopted blue/green deployments and fast rollback criteria.
  • Implemented OAuth2/JWT security with Cognito/Azure AD integrations, RBAC, and audit trails; encrypted sensitive data using KMS and enforced least-privilege access policies.
  • Added observability across services using OpenTelemetry tracing, Prometheus metrics, and dashboards/alerts (Grafana/CloudWatch), reducing incident triage time and improving SLO compliance.
  • Delivered Web3/blockchain integrations (wallet auth and smart-contract interaction for verification/audit use-cases) with secure signing flows and backend verification services.
  • Led code reviews, mentoring, and architecture reviews; introduced engineering standards (API design, testing strategy, runbooks) that improved delivery predictability and maintainability.
Aug 2018 - Jun 2021
2 years 11 months

Full Stack Engineer

data.ai (by Sensor Tower)

  • Delivered a data-intensive analytics SaaS platform using TypeScript/React on the frontend and Python/Node.js services on the backend to support enterprise reporting and dashboards.
  • Built ingestion and transformation services in Python and Java that processed high-volume telemetry, including schema evolution, validation, deduplication, and backfills.
  • Designed performant data access layers on PostgreSQL and Redis, tuning indexes and query plans; reduced expensive report execution time by up to ~30%.
  • Implemented asynchronous job orchestration for batch reports and scheduled analytics, keeping interactive APIs responsive during heavy processing windows.
  • Introduced GraphQL for complex read use-cases, improving frontend developer experience and reducing the number of client round trips for multi-entity views.
  • Developed reusable UI primitives and data-visualization patterns in React, improving accessibility and standardizing UX across product areas.
  • Implemented secure auth flows (OAuth2/JWT) and service-to-service access patterns; contributed to RBAC models used across internal tools and customer-facing portals.
  • Added ML-assisted enrichment (NLP tagging, entity resolution) to improve data quality; collaborated with data science teams to operationalize model outputs in production workflows.
  • Containerized services with Docker and standardized CI/CD with automated tests and linting; improved deployment safety and reduced configuration drift between environments.
  • Improved observability by adding structured logs, metrics, and health checks; partnered with SRE to define alerts and reduce MTTR for incidents.
  • Optimized API performance through caching and pagination strategies; reduced payload sizes and improved client rendering times for large tables.
  • Worked directly with product stakeholders to translate business questions into measurable KPIs and reliable data products, owning deliverables from design through launch.
Feb 2016 - Jul 2018
2 years 6 months

Software Engineer

Storyteq

  • Built enterprise content/marketing platforms using Java (Spring Boot/Spring Cloud), Python services, and Angular frontends, supporting multi-tenant configuration and enterprise RBAC.
  • Designed microservices around campaign orchestration, asset pipelines, and integrations, enabling independent releases and improved fault isolation.
  • Implemented real-time dashboards using WebSockets and event-driven backends to provide live operational visibility for support and marketing teams.
  • Built REST APIs with OpenAPI/Swagger documentation, consistent error models, and versioning strategies to reduce client breakage during iterative delivery.
  • Integrated third-party APIs and internal services using resilient patterns (timeouts, retries, circuit breakers) to improve reliability under dependency failures.
  • Standardized CI/CD with Jenkins/Azure DevOps pipelines, reducing manual deployment steps and improving release predictability.
  • Introduced centralized observability using OpenTelemetry instrumentation and Prometheus/Grafana dashboards to shorten detection time for performance regressions.
  • Optimized service performance through SQL tuning, caching strategies, and payload reduction; maintained stable response times during high-traffic campaigns.
  • Implemented security improvements including token lifecycle management, least-privilege access policies, and dependency hygiene to reduce high-severity findings.
  • Supported cloud migrations and containerized workloads; contributed to Kubernetes deployment manifests and environment standardization across staging/production.
  • Partnered with QA and product on acceptance criteria and test strategy; improved release confidence through targeted integration tests and smoke suites.
  • Provided on-call support and root-cause analysis; documented runbooks and preventive fixes to reduce repeat incidents.
Oct 2014 - Jan 2016
1 year 4 months

Full Stack Engineer

Attract Group

  • Designed and maintained websites and eCommerce platforms using PHP (Laravel/CodeIgniter) and JavaScript, implementing core business logic for catalog, checkout, and order workflows.
  • Built responsive, mobile-first UIs and reusable components with Vue.js, HTML5, and CSS3 to improve usability across devices and increase conversion.
  • Implemented secure payment integrations (Stripe/PayPal and custom gateways), ensuring safe callback handling, clear reconciliation, and protection against replay attacks.
  • Developed admin dashboards and CMS tools for non-technical operators (content blocks, media uploads, configurable pages), improving operational efficiency.
  • Created REST endpoints and server-side validation for transactional flows; improved reliability through robust error handling and logging.
  • Optimized MySQL/PostgreSQL schemas and queries with indexing and query tuning; improved page and API response times for high-traffic pages.
  • Introduced background processing for emails, exports, and long-running tasks to keep request latency low and improve user experience.
  • Improved SEO and performance via asset minification, caching headers, image optimization, and lazy-loading strategies; increased Lighthouse scores for key landing pages.
  • Standardized Git workflows and CI checks to reduce regression risk and support parallel feature development.
  • Worked closely with stakeholders to clarify requirements, estimate scope, and deliver pragmatic solutions under timeline constraints.
  • Supported production incidents with debugging and root-cause analysis; implemented preventive fixes and documentation to reduce repeat issues.
  • Contributed to code quality improvements through refactoring and peer reviews; maintained clear release notes for client-facing changes.

Summary

Senior Software Engineer with 10+ years of experience architecting and delivering high-performance, secure, and scalable full-stack products. Expert across Python, JavaScript/TypeScript, Java, C#, PHP, and Go, with modern frontend delivery using React, Angular, Vue.js, Next.js, and Nuxt.js. Proven track record modernizing monoliths into Docker/Kubernetes microservices, building REST/GraphQL APIs, and shipping applied AI features such as LLM-assisted workflows, NLP pipelines, RAG, and semantic search using LangChain. Strong focus on performance tuning, reliability engineering, CI/CD automation, and translating complex business requirements into maintainable system designs.

Selected highlights

  • Modernized legacy platforms into microservice and event-driven architectures using Python, Node.js, .NET Core, and Spring Boot, improving deployment frequency and reducing operational risk.
  • Built AI-powered product features (LLM/NLP, semantic search, RAG) with LangChain and vector indexing to automate knowledge workflows and accelerate user decision-making.
  • Delivered responsive web and mobile experiences with React, Next.js, Angular, and Vue.js, improving conversion and UX through performance and accessibility optimization.
  • Implemented cloud-native delivery on AWS with Docker, Kubernetes (EKS), Terraform, and CI/CD, supported by production observability (OpenTelemetry/Prometheus/Grafana).

Skills

Languages

  • Python
  • Javascript (Es6+)
  • Typescript
  • Java
  • C#
  • Php
  • Go
  • Sql
  • Bash

Frontend

  • React
  • Angular
  • Vue.js
  • Next.js
  • Nuxt.js
  • React Native
  • Html5
  • Css3
  • Tailwind
  • Bootstrap

Backend & Apis

  • Node.js
  • Django
  • Flask
  • Fastapi
  • Spring Boot
  • Spring Cloud
  • .Net Core
  • Laravel
  • Rest
  • Graphql (Apollo)
  • Grpc
  • Openapi/swagger

Ai / Data

  • Llm Integration
  • Nlp Pipelines
  • Langchain
  • Rag
  • Embeddings
  • Semantic Search
  • Vector Databases
  • Model-serving Via Api And Background Workers

Messaging

  • Kafka
  • Rabbitmq
  • Sqs/sns
  • Background Processing
  • Retries
  • Idempotency
  • Dlq Patterns

Datastores

  • Postgresql
  • Mysql
  • Mongodb
  • Redis
  • Elasticsearch
  • Indexing
  • Query Tuning
  • Caching Strategies

Cloud / Devops

  • Aws (Eks, Ec2, S3, Lambda, Rds, Cloudfront, Cognito, Kms, Cloudwatch)
  • Docker
  • Kubernetes
  • Terraform
  • Ci/cd (Github Actions, Codepipeline, Jenkins, Azure Devops)

Security / Quality

  • Oauth2
  • Jwt
  • Rbac
  • Secure Webhooks
  • Secrets Management
  • Soc 2-aligned Controls
  • Test Automation (Unit/integration)
  • Code Review Standards

Architecture

  • Microservices
  • Event-driven Architecture
  • Ddd
  • Cqrs
  • Clean Architecture
  • Observability (Opentelemetry, Prometheus, Grafana)

Languages

Polish
Native
English
Advanced

Education

Apr 2010 - Sep 2014

London Metropolitan University

Bachelor of Science · Computer Science · London, United Kingdom

Certifications & licenses

AWS Certified Developer

Azure Fundamentals

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