Senior JavaScript Developer (Node.js / TypeScript)

3 873 - 5 809 USDNet per month - B2B
JavaScript

Senior JavaScript Developer (Node.js / TypeScript)

JavaScript
Sarmacka 22, Warszawa

Hypris

Full-time
B2B
Senior
Remote
3 873 - 5 809 USD
Net per month - B2B

Job description

Hypris is an AI-driven productivity and workflow automation platform that centralizes data, communication, and business processes in one system.


We are past the idea stage:

  • MVP in production,

  • paying customers from multiple industries,

  • ongoing onboarding and real-life implementations,

  • active fundraising process with advanced investor discussions.


Hypris is built as a modular, multi-tenant SaaS combining CRM, workflow automation, internal communication, and data management, with a strong focus on secure, scalable architecture and AI-assisted automation.

You will join the project at a critical scaling phase, where architectural, security, and organizational decisions have long-term impact.


Your role

As a Senior JavaScript Developer, you will play a key role in shaping both the technology and the product direction of the platform.

This role goes beyond standard development work. You will not only build core backend systems, but also have real influence on architectural decisions, technical standards, and future development direction.


Responsibilities

  • Design and develop scalable backend services in Node.js and TypeScript

  • Build and maintain secure REST APIs for web and mobile clients

  • Co-create and evolve the long-term backend and system architecture

  • Apply and promote security best practices across the platform (OWASP Top 10)

  • Identify and mitigate common security risks in web applications

  • Work with data-intensive, multi-tenant, workflow-driven systems

  • Integrate third-party services and internal platform modules

  • Define and uphold coding standards and best practices

  • Review code and mentor less experienced developers

  • Support CI/CD pipelines and Docker-based environments


Requirements (Senior level)

  • 5+ years of commercial experience in software development

  • Strong proficiency in JavaScript and TypeScript

  • Solid experience with Node.js backend development

  • Very good understanding of software architecture and system design

  • Practical experience with REST API design

  • Knowledge of SQL and NoSQL databases

  • Strong understanding of OOP and SOLID principles

  • Experience working on production systems with real users

  • Ability to work independently and take ownership of technical decisions

  • Good command of English (technical communication)

  • Practical knowledge of web application security best practices

  • Understanding of OWASP Top 10 and ability to apply it in real systems

  • Experience designing secure authentication and authorization mechanisms

  • Awareness of common vulnerabilities (XSS, SQL Injection, CSRF, IDOR)

  • Ability to safely handle sensitive data and secrets


Nice to have

  • Experience with mobile applications (React Native / Expo or similar)

  • DevOps experience:

    • CI/CD pipelines

    • Docker

    • cloud platforms (AWS / GCP / similar)

  • Experience with multi-tenant SaaS systems

  • Familiarity with AI / LLM-based integrations

  • Frontend experience with Vue.js or React.js


Technology stack

  • JavaScript / TypeScript

  • Node.js

  • Vue.js (web)

  • MongoDB + SQL

  • Docker

  • GitHub + CI/CD

  • Jest


Growth, impact & ownership

This role is designed for a developer who wants to actively shape a product, not just implement tasks.

You will have:

  • real influence on product and technology direction,

  • ownership of key technical areas (architecture, security, core backend modules),

  • involvement in building and mentoring the development team as it grows,

  • close collaboration with the founders and product owners,

  • insight into business, scaling and fundraising decisions.

For long-term cooperation, we plan to introduce a future equity / option program, tied to company growth and key milestones.


What we offer

  • High-impact role in a growing product with paying customers

  • Early-stage project with a clear scaling and investment roadmap

  • Fully remote work with occasional team meetups

  • Flat structure and fast decision-making

  • Modern stack, no legacy codebase

  • Access to modern tools (incl. Cursor)

  • Opportunity to naturally grow into a Lead / Principal engineering role


Recruitment process

  • Short technical call

  • Practical technical discussion (no LeetCode)

  • Fast decision process

Tech stack

    Polish

    C1

    English

    B2

    JavaScript

    master

    TypeScript

    master

    Node.js

    master

    Vue.js

    master

    MongoDB

    advanced

    Docker

    advanced

    Jest

    advanced

    DevOps

    advanced

Office location

Published: 08.01.2026

Senior JavaScript Developer (Node.js / TypeScript)

3 873 - 5 809 USDNet per month - B2B
Summary of the offer

Senior JavaScript Developer (Node.js / TypeScript)

Sarmacka 22, Warszawa
Hypris
3 873 - 5 809 USDNet per month - B2B
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