Senior Full-Stack Engineer (React/Node.js)

Our client builds post-quantum cryptography solutions that help enterprises assess and manage cryptographic risk. Their flagship platform inventories cryptographic assets (certificates, keys, algorithms) across enterprise infrastructure and analyzes vulnerabilities against post-quantum threats. The platform serves the government, finance, and utilities sectors where cryptographic security is critical.

We are looking for a Senior Full-Stack Engineer to join a migration project transforming the platform from single-tenant deployments to a multi-tenant, multi-cloud architecture. You’ll work on both React frontend and Node.js backend, implementing tenant isolation, hierarchical access control, and cloud-agnostic deployment patterns. This role requires in-depth backend expertise with a secondary front-end skill, focusing on containerized microservices, database architecture, and complex data migrations.

You’ll collaborate with a solutions architect, DevOps engineer, QA team, and the client’s development team to deliver a proof-of-concept by January 2026, followed by production migration over the remaining contract period. The project starts with discovery and architecture design in early December 2025, with hands-on development ramping up through the 6-month engagement.

Technical Details:

• Frontend: React (JavaScript), Nginx

• Backend: Node.js, Express, JavaScript

• Database: PostgreSQL (relational data, users, scoring rules), Elasticsearch (cryptographic facts, analytics)

• Authentication: OIDC/SSO (integration TBD), certificate-based service authentication

• Infrastructure: Docker (containerization), Docker Compose (local dev only), AWS EC2 (current single-tenant), ECS/Fargate (production deployment, DevOps-managed), multi-cloud target architecture

• Services: SSLyze (network probe), Bootstrap CA (internal PKI), SSL/TLS throughout

• Testing: Zeuz (integration tests), unit testing framework (TBD during restoration)

• CI/CD: GitHub (existing), deployment automation (TBD)

• Observability: TBD (logging, monitoring, error tracking)

Team composition: Tech Lead, 2 Software Engineers, QA Engineers, DevOps Engineer, Delivery Manager

Job Highlights:

• Architect and implement multi-tenant isolation patterns across Elasticsearch and PostgreSQL

• Work on platformizing a post-quantum cryptography product for scalable deployment (no cryptography expertise required — our focus is on multi-tenant architecture and deployment automation)

• Solve complex technical challenges: tenant-aware data segregation, multi-cloud portability, zero-downtime migrations

• Modern containerized microservices architecture with Docker, Elasticsearch, and certificate-based authentication

• Multi-tenancy implementation with architectural freedom and migration strategy ownership

• Collaborate directly with client CTO and lead developer on high-impact architectural decisions

What you'll work on

• Multi-tenant architecture implementation: Implement tenant isolation models for Elasticsearch (cryptographic facts) and PostgreSQL (users, scoring rules, metadata), design component-level solutions for tenant-aware queries and data segregation, and develop tenant ID propagation across all services.

• Full-stack feature development: Build React frontend features for partner–customer–user hierarchy management, implement Node.js backend APIs for multi-tenant CRUD operations, and develop tenant-scoped analytics and reporting interfaces.

• Authentication and access control: Integrate OIDC/SSO authentication, implement role-based access control (RBAC) for hierarchical tenancy (partners → customers → users), and build admin interfaces for user and access management.

• Data migration and transformation: Plan and execute migration from single-tenant to multi-tenant data models, implement zero-downtime migration strategies with rollback capabilities, and build data validation and integrity checks.

• Backend API development: Extend Node.js/Express REST APIs for tenant-aware operations and optimize query performance for multi-tenant Elasticsearch and PostgreSQL.

• Containerization and deployment support: Work with Docker to containerize services (backend, frontend, Postgres, Elasticsearch, SSLyze network probe), contribute to multi-cloud deployment architecture discussions, and ensure applications are deployment-ready for container orchestration platforms.

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Responsibilities

• Implement multi-tenant data isolation patterns in Elasticsearch and PostgreSQL, including tenant namespace conventions and data segregation across all service layers

• Build React frontend components for hierarchical tenant management (partners, customers, users) and tenant-scoped dashboards

• Develop Node.js backend APIs with tenant-aware routing, query filtering, and data segregation enforcement

• Implement OIDC/SSO integration and role-based access control (RBAC) for multi-level tenant hierarchy

• Create data migration scripts and zero-downtime migration strategies for existing single-tenant deployments with validation and rollback capabilities

• Ensure multi-tenant queries perform efficiently in Elasticsearch and PostgreSQL without degrading existing performance

• Implement automated testing (unit and integration) for tenant isolation and data segregation scenarios

• Work with Docker to containerize applications and ensure deployment readiness for production orchestration platforms

• Collaborate with the solutions architect on technical decisions, migration planning, architecture documentation, and component-level design proposals

• Conduct code reviews, ensuring tenant isolation security, query performance, and adherence to multi-tenancy patterns

• Partner with a DevOps engineer on container orchestration and cloud-agnostic infrastructure, and with the QA team on test case definition for cross-tenant data leakage scenarios

• Participate in sprint planning, daily standups, and weekly client syncs with leadership and the development team

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Qualifications

• 5+ years of full-stack development experience with React and Node.js in production environments

• Experience using AI-powered productivity tools (Cursor, VS Code with Copilot, or similar AI-enhanced IDEs) and LLMs for research and problem-solving (ChatGPT, Claude, etc.)

• Strong proficiency in React and modern JavaScript (ES6+) for building complex user interfaces

• Solid experience with Node.js and Express building REST APIs with authentication and authorization

• Deep understanding of PostgreSQL, including query optimization, indexes, migrations, and transaction management

• Hands-on experience with ElasticSearch, including index design, query DSL, aggregations, and performance tuning

• Strong knowledge of multi-tenant architecture patterns (schema isolation, row-level security, tenant namespacing)

• Experience with Docker and containerized microservices architectures in production

• Understanding of authentication patterns (OIDC, SSO, JWT, session management, RBAC)

• Experience with data migrations, including strategy design, validation, and rollback procedures

• Strong understanding of software design patterns and architectural principles for building maintainable, scalable systems

• Strong problem-solving skills and ability to work autonomously with minimal oversight

• Clear written and spoken English for async collaboration and documentation

Nice to Have

• Experience with multi-cloud deployments (AWS, Azure, GCP) and cloud-agnostic architecture patterns

• Familiarity with container orchestration platforms (ECS, EKS, Kubernetes)

• Knowledge of the Elasticsearch Painless scripting language

• Experience with cryptography concepts, PKI, certificate management, or security assessment tools

• Familiarity with certificate-based authentication and SSL/TLS security practices

• Background in migrating legacy single-tenant applications to multi-tenant SaaS architectures

• Experience with zero-downtime deployment strategies and blue-green migrations

• Familiarity with TypeScript (potential future migration from JavaScript)

• Knowledge of test automation frameworks for integration testing (experience with Zeuz is a plus)

• Understanding of post-quantum cryptography or cybersecurity domains

• Experience working with government, finance, or utilities sector security requirements

• Familiarity with partner/reseller SaaS models and hierarchical tenant structures

• Knowledge of observability tools (logging, monitoring, error tracking, APM)

• Background in architecture projects involving data model migrations

• GitHub-based workflows and conventional commits

Our benefits:

• No micromanagement

• Freedom to engage in decision-making and implementation

• Ability to work in a team of professionals (the ratio of middle and above specialists 80/20)

• Participation in the development of high-quality products

• Direct communication with clients on a partnership level

• Professional development opportunities ($600 education budget, well-managed processes, communities, internal library)

• Health insurance

• $600 extra for health care, sports, or mental health

• 20 paid working days off and 10 days sick leave

• Opportunity to work remotely

• Soulful team buildings and corporate events

  
  

Join us and be among those who care!

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