Lead Full-Stack Engineer (NestJS and React)

About the project:Our customer is a full quote-to-cash ERP/PSA used by field service companies (system integrators) that install and maintain physical equipment - AV systems, security cameras, fire alarms, HVAC. The platform covers:Sales: opportunities, quoting, orderingProjects: project management, resource schedulingService: dispatch, ticketing, field technician managementFinance: accounting, GL, invoicing, purchasing (the financial core is central to everything)Reporting: data sources, dashboards, report builderAll modules feed into a single financial core. The platform is sold as an all-or-nothing product today - no modular subscriptions.You will work closely with stakeholders to analyze the current solution, identify technical risks, document findings, and provide recommendations that will shape future development. This is an excellent opportunity for an experienced engineer who enjoys solving complex technical challenges, investigating legacy systems, and making architectural decisions.Requirements7+ years of commercial software engineering, with Backend and Frontend development using TypeScriptHands-on experience with NestJS and ReactHands-on experience with REST API and GraphQL protocolsProven track record leading engineering teams - technical mentorship, code reviews, architectural decisions.Strong experience working with complex backend systems (beyond CMS platforms or simple websites). Experience with ERP systems is a significant advantage.Solid understanding of distributed and microservices-based architectures.Strong expertise with relational databases (MySQL, PostgreSQL, or similar), including schema design, query optimization, and performance analysis.Experience working with stored procedures, database functions, and complex SQL is highly desirable.Experience with Apache KafkaExperience analyzing large legacy codebases and understanding complex business logic.Hands-on experience with reverse engineering existing systems is a strong plus.Experience participating in system design, architecture discussions, and technical decision-making.Strong analytical mindset and excellent problem-solving skills.Ability to work independently with limited project documentation.Hands-on experience with Azure CloudUpper-Intermediate or higher English level.Experience working in Agile / Scrum / KanbanPHP and MSSQL stored procedures experience is a significant advantage.Nice to HaveExperience with AI-assisted development tools (Copilot, Claude, Cursor)Background in SaaS, multi-tenant platforms, or large-scale B2B portalsResponsibilitiesLead technical delivery, owning architecture and code qualityDesign, develop, and review TypeScript code for backend and frontend systemsAlign with Client engineering leadership on technical direction and deliveryBreak down epics into technical tasks, drive estimation and sprint planningMentor engineers through pair programming, code reviews, and technical guidanceDrive AI adoption by onboarding teammates to AI tools and practicesIdentify and unblock technical risks early; escalate delivery concerns proactivelyParticipate in Agile ceremonies and Client governance cadenceContribute to Roadmap planning, risk identification, and dependency managementWe offer*:Flexible working format - remote, office-based or flexibleA competitive salary and good compensation packagePersonalized career growthProfessional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)Active tech communities with regular knowledge sharingEducation reimbursementMemorable anniversary presentsCorporate events and team buildingsOther location-specific benefitsnot applicable for freelancers