Senior Fullstack Engineer

Lumnix

Location
Remote
Employment
Full-time
Level
Specialist
Category
Full-stack
Posted

Description

Role Overview

We are looking for a Senior Fullstack Engineer to help design, build, and evolve core product functionality across the frontend, backend, and data layers.

This is a hands-on role with real ownership. You will work closely with Product, QA, and other engineers to deliver features end-to-end, from API design and UI behavior to data correctness.

This is not a people-management role. It is focused on shipping high-quality software in a

complex, data-driven environment.

What You’ll Do

  • Design and build end-to-end product features, from the UI and backend logic to

database interactions.

  • Implement and evolve core workflows, including:

o Data ingestion and connector management.

o Metrics configuration and overrides.

o Time-based grouping across daily, weekly, monthly, quarterly, and yearly periods.

o Forecasting, reporting, and analytics views.

  • Build and maintain clean, well-structured APIs.
  • Work within a modular monolith backend, contributing to shared domain logic and

internal service boundaries.

  • Write efficient, readable SQL for data retrieval, aggregation, and validation.
  • Ensure the correctness of financial calculations and aggregations.
  • Collaborate closely with:

o Product on requirements and edge cases.

o QA on testability and bug resolution.

o Other engineers on architecture and code quality.

  • Review code and contribute to technical standards and best practices.
  • Participate in release planning and production readiness.

Required Skills and Experience

  • 5+ years of professional software engineering experience.
  • Strong experience building fullstack web applications.
  • Solid frontend experience with:

o React.

o TypeScript.

o Modern component-based UI patterns.

  • Strong backend experience with Node.js-based API services, including business logic and data validation.

Strong SQL skills, including:

o Writing complex queries.

o Working with aggregations and joins.

o Reasoning about data correctness and performance.

  • Experience working with relational databases. PostgreSQL is preferred.
  • Comfort working in production systems with real users and data.
  • Ability to reason about edge cases, failure modes, and data consistency.

Nice to Have

  • Experience with financial, analytics, or reporting platforms.
  • Experience working in early-stage or startup environments.
  • Exposure to Python is a plus, although the core backend is implemented in Node.js.

What Success Looks Like in the First 90 Days

  • You understand the platform’s data model and core product flows.
  • You ship multiple production features end-to-end.
  • Your code is readable, testable, and trusted by the team.
  • You proactively surface edge cases and data issues.
  • Product and QA rely on you for clarity and execution

Apply at the source

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View & apply on djinni.co ↗