Recommended expert
Jakub Song
Full-Stack Engineer
Experience
Jan 2023 - Present
3 years 1 monthFull-Stack Engineer
Bemlo
- Built and maintained advanced scheduling, staffing-pool, and worker availability features using React + TypeScript, focusing on complex UI logic, calendar-heavy views, and real-time state updates. These improvements reduced time spent by healthcare managers coordinating shifts and increased adoption among large hospital units.
- Designed efficient PostgreSQL schemas for worker preferences, staffing rules, labor law constraints, and unit-level coverage metrics. The new structure enabled dramatically faster lookups during scheduling operations and reduced overall query cost in heavy-load scenarios.
- Developed a distributed scheduling engine using Node.js, orchestrated with Redis queues, supporting parallel execution of rule checks, constraint evaluation, and conflict resolution across thousands of workers. This architecture improved generation speed by nearly 10× compared to the previous implementation.
- Implemented SSO (Azure AD), role-based access control, and detailed audit logging across all employer-facing modules, ensuring compliance with regional healthcare security requirements and simplifying onboarding for large organizations.
- Built real-time dashboards using WebSockets / pub-sub for conflict detection, coverage insights, and shift alerts. These updates enabled managers to respond to staffing gaps in minutes instead of hours.
- Deployed microservices using Docker + AWS ECS and automated the entire CI/CD lifecycle with GitHub Actions, improving release frequency and lowering deployment risk during critical scheduling periods.
- Created developer tools and observability dashboards that made debugging rule failures and schedule conflicts significantly easier for the engineering team.
Jan 2021 - Dec 2022
2 yearsSoftware Engineer
Ambience Healthcare
- Delivered major clinical workflow features using React + TypeScript, building complex UI flows for real-time transcription, chart review, and note editing. Focused on lowering cognitive load for clinicians and reducing manual documentation tasks.
- Integrated ML/NLP inference pipelines into backend workflows using Node.js, enabling real-time speech-to-text, summarization, and auto-generated structured data. Improved stability and latency for inference-heavy endpoints supporting medical visits.
- Designed and implemented GraphQL + REST APIs for clinical sessions, encounters, transcription processing, provider workspaces, and note management, ensuring consistent data flow between frontend, backend, and ML services.
- improved frontend performance by revamping state architecture with React Query, reducing unnecessary re-renders, stabilizing long forms, and improving perceived responsiveness during live transcription.
- Built secure data storage flows using PostgreSQL, encrypted fields, and RBAC-based access control to ensure HIPAA compliance. Worked closely with internal compliance teams to meet stringent healthcare data retention rules.
- Automated releases and environment scaling using Docker + GitHub Actions, supporting fast iteration cycles during customer trials and clinician onboarding.
- Collaborated with ML engineers to fine-tune model interfaces, optimize cold-start times, and improve reliability during high-load periods such as clinic peak hours.
Jan 2018 - Dec 2021
4 yearsFull-Stack Developer
Wunderdog
- Led development of full-stack features using React, Next.js, Node.js, FastAPI, working closely with client teams to deliver reliable user-facing experiences under tight project timelines. Focused on robust UI design, maintainable code, and predictable performance.
- Designed and implemented backend workflows, reporting dashboards, and automation tools across fintech and logistics systems. Leveraged PostgreSQL and MongoDB to optimize complex data relationships and reduce query overhead.
- Built secure identity and access flows using OAuth2, JWT, and RBAC, including multi-tenant support for enterprise clients with strict permission requirements.
- Integrated third-party services such as Stripe (payments), Mapbox (maps and routing), and internal analytics systems, ensuring smooth data flow and high uptime.
- Implemented CI/CD pipelines using Docker + GitHub Actions, introducing automated testing, artifact packaging, and multi-environment deploys that significantly accelerated release cycles.
- Worked directly with stakeholders to define architecture choices, prioritize features, scope MVPs, and transform requirements into technical plans. Helped teams avoid over-engineering by choosing simple, scalable patterns.
- Led debugging and optimization work on production systems, resolving performance bottlenecks, reducing response times, and improving reliability for users across Europe.
Jan 2015 - Dec 2018
4 yearsJunior Software Developer
Microsoft
- Built backend automation and orchestration tools using C#/.NET, enabling engineering teams to streamline deployment tracking, reporting, and workflow management. Focused on reliability, error handling, and high uptime.
- Developed interactive dashboards and internal UI components using JavaScript + enterprise UI frameworks, making large datasets more accessible to technical and non-technical stakeholders.
- Designed SQL Server queries, ETL pipelines, and API integrations for large engineering datasets, reducing latency and improving the accuracy of internal KPIs and metrics.
- Improved job performance and processing speed by refactoring service flows, optimizing I/O patterns, and redesigning long-running automation tasks.
- Implemented full test coverage using xUnit + MSTest, improving reliability of services deployed across multiple engineering teams.
- Integrated internal messaging, authentication, logging, and monitoring services to ensure compliance with Microsoft’s enterprise security standards.
- Collaborated with teams across multiple time zones, aligning roadmap decisions and delivering features under strict security and performance constraints.
Summary
Full-Stack Software Engineer with 9+ years of experience building AI-driven healthcare products, automated scheduling engines, and high-scale SaaS platforms. Strong across the full stack with React, TypeScript, Node.js, Python, PostgreSQL, Redis, Docker, and AWS, delivering features end-to-end from design to production. Hands-on experience integrating NLP/ML pipelines, real-time transcription, AI-generated clinical notes, and rule-based decision systems into production environments. Skilled at designing clean architecture, optimizing performance under heavy workloads, and building secure data flows for regulated industries. Focused on creating fast, reliable user experiences while scaling backend systems that support complex AI workflows and high-demand operational tooling.
Skills
Frontend
- Styled Components
- React
- Mui
- React Query
- Tailwind
- Next.js
- Typescript
- Redux
Backend
- Unix
- Python
- Django
- Fastapi
- Node.js
- Nestjs
- Express
- Go
- Rest Apis
- Graphql
- Websockets
Cloud & Infrastructure
- Aws Lambda
- Aws Ecs
- Aws Sqs
- Aws Sns
- Aws Dynamodb
- Aws S3
- Aws Api Gateway
- Aws Step Functions
- Aws Cloudwatch
- Docker
- Terraform
- Kubernetes
Databases
- Postgresql
- Mysql
- Mongodb
- Dynamodb
- Redis
- Data Modeling
- Query Optimization
Devops
- Github Actions
- Circleci
- Ci/cd
- Observability
- Monitoring & Alerts
- Performance Profiling
Others
- Stripe
- Nlp/ml Apis
- Openai
- Mapbox
Languages
English
AdvancedPolish
IntermediateEducation
Oct 2010 - Jun 2015
AGH University of Krakow
Bachelor of Science, Computer Science · Computer Science · Kraków, Poland
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