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.
What’s interesting about this project: * 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.
Note: The DevOps engineer will handle production infrastructure provisioning, CI/CD pipelines, and container orchestration (ECS/Fargate or similar). A solutions architect provides architecture guidance and technical leadership during the discovery phase.
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.
Requirements: * 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 * Accounting services * 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!
Please note: the review process may take up to 7 days. If your experience aligns with what we’re looking for, we’ll reach out to discuss the next steps. If not, we’ll hang onto your details and let you know if something relevant opens up.
