Fullstack Developer for Legacy Platform Optimization
Budget: €750 – €1,500 EUR
NestJS, React, TypeScript — Legacy Platform Modernisation
ONLY APPLY IF
You are fluent in English
You have a suitable remote work setup
MacBook or equivalent development machine
HD webcam
Good microphone
Reliable internet connection
About the Role
We are looking for a Mid/Senior Fullstack Developer to help maintain, improve, and modernise an existing production platform built with NestJS, React, and TypeScript.
This is not a greenfield rebuild. You will be working on a real, established product with existing users, legacy decisions, technical debt, and production constraints.
We are looking for someone pragmatic who can understand an existing codebase, improve it safely, ship features, fix bugs, and help move the platform forward without over-engineering.
You’ll work closely with the CTO and product team to support ongoing development, stabilise core systems, and gradually improve the quality, maintainability, and performance of the platform.
Tech Stack
Frontend: React, TypeScript
Backend: NestJS, Node.js, TypeScript
APIs: REST and GraphQL
Database: PostgreSQL
Infrastructure: Cloud-based deployment, CI/CD
Tooling: GitHub, issue tracking, modern AI-assisted development tools
What You’ll Work On
Maintaining and improving an existing React application
Building and updating backend services in NestJS
Fixing bugs and production issues
Refactoring legacy code safely
Improving performance and reliability
Building new product features within the existing architecture
Improving API design and data flows
Adding and improving tests where needed
Supporting platform stability and long-term maintainability
Responsibilities
Work across frontend and backend systems
Understand existing code and make safe, incremental improvements
Build clean, maintainable features in React and NestJS
Debug issues across the stack
Improve technical debt without unnecessary rewrites
Write clear, practical TypeScript
Work with PostgreSQL and application data models
Review code and contribute to engineering standards
Communicate clearly in an async remote environment
Take ownership of tasks from investigation through to delivery
What We’re Looking For
Experience
4+ years of professional software engineering experience
Strong experience with TypeScript
Strong experience with React
Experience building APIs with Node.js
Experience with NestJS or similar backend frameworks
Comfortable working with PostgreSQL
Experience maintaining or improving legacy systems
Comfortable debugging production issues
Strong In
React
TypeScript
Node.js
NestJS
REST APIs
GraphQL APIs
PostgreSQL
Git workflows
Clean, maintainable code
Nice to Have
Experience with any of the following is a bonus:
Legacy platform modernisation
Large existing React codebases
Monorepos
CI/CD pipelines
Testing with Vitest, Jest, Playwright, or similar
Cloudflare, AWS, GCP, or similar cloud platforms
Performance optimisation
AI-assisted development tools such as Claude Code, Codex, Cursor, or similar
Mindset
We are looking for someone who is:
Pragmatic and product-focused
Comfortable working in an existing codebase
Able to improve systems incrementally
Clear and honest in communication
Reliable in a remote-first team
Comfortable asking questions when needed
Able to balance speed with quality
Not afraid of legacy code
Interested in long-term platform improvement
How We Work
Remote-first
Async-friendly
Small team
High ownership
Direct access to the CTO
Practical, product-led engineering
Focused on shipping useful improvements
Why Join Hablo
Work on a real production platform with active users
Help modernise and improve important core systems
Have direct influence over technical direction
Join a small, high-trust team
Own meaningful work end-to-end
Help move Hablo from legacy systems toward a stronger in-house engineering foundation
Compensation and Benefits
Competitive, location-based salary
Remote-first working
AI development tools covered where useful
Home office support
Learning and development budget
Flexible working environment
Important Note
This role is best suited to someone who enjoys improving existing systems, not someone who only wants to work on brand-new projects.
We need a developer who can understand what already exists, make it better, and help us move quickly without breaking production.
Hires remotely in
Europe
Remote work policy
Remote only
Company Location
London
Job type
Full Time
Visa sponsorship
Not Available
Preferred timezones
Coordinated Universal Time, Central European Time
Relocation
Not Allowed
Experience
5+ years
ONLY APPLY IF
You are fluent in English
You have a suitable remote work setup
MacBook or equivalent development machine
HD webcam
Good microphone
Reliable internet connection
About the Role
We are looking for a Mid/Senior Fullstack Developer to help maintain, improve, and modernise an existing production platform built with NestJS, React, and TypeScript.
This is not a greenfield rebuild. You will be working on a real, established product with existing users, legacy decisions, technical debt, and production constraints.
We are looking for someone pragmatic who can understand an existing codebase, improve it safely, ship features, fix bugs, and help move the platform forward without over-engineering.
You’ll work closely with the CTO and product team to support ongoing development, stabilise core systems, and gradually improve the quality, maintainability, and performance of the platform.
Tech Stack
Frontend: React, TypeScript
Backend: NestJS, Node.js, TypeScript
APIs: REST and GraphQL
Database: PostgreSQL
Infrastructure: Cloud-based deployment, CI/CD
Tooling: GitHub, issue tracking, modern AI-assisted development tools
What You’ll Work On
Maintaining and improving an existing React application
Building and updating backend services in NestJS
Fixing bugs and production issues
Refactoring legacy code safely
Improving performance and reliability
Building new product features within the existing architecture
Improving API design and data flows
Adding and improving tests where needed
Supporting platform stability and long-term maintainability
Responsibilities
Work across frontend and backend systems
Understand existing code and make safe, incremental improvements
Build clean, maintainable features in React and NestJS
Debug issues across the stack
Improve technical debt without unnecessary rewrites
Write clear, practical TypeScript
Work with PostgreSQL and application data models
Review code and contribute to engineering standards
Communicate clearly in an async remote environment
Take ownership of tasks from investigation through to delivery
What We’re Looking For
Experience
4+ years of professional software engineering experience
Strong experience with TypeScript
Strong experience with React
Experience building APIs with Node.js
Experience with NestJS or similar backend frameworks
Comfortable working with PostgreSQL
Experience maintaining or improving legacy systems
Comfortable debugging production issues
Strong In
React
TypeScript
Node.js
NestJS
REST APIs
GraphQL APIs
PostgreSQL
Git workflows
Clean, maintainable code
Nice to Have
Experience with any of the following is a bonus:
Legacy platform modernisation
Large existing React codebases
Monorepos
CI/CD pipelines
Testing with Vitest, Jest, Playwright, or similar
Cloudflare, AWS, GCP, or similar cloud platforms
Performance optimisation
AI-assisted development tools such as Claude Code, Codex, Cursor, or similar
Mindset
We are looking for someone who is:
Pragmatic and product-focused
Comfortable working in an existing codebase
Able to improve systems incrementally
Clear and honest in communication
Reliable in a remote-first team
Comfortable asking questions when needed
Able to balance speed with quality
Not afraid of legacy code
Interested in long-term platform improvement
How We Work
Remote-first
Async-friendly
Small team
High ownership
Direct access to the CTO
Practical, product-led engineering
Focused on shipping useful improvements
Why Join Hablo
Work on a real production platform with active users
Help modernise and improve important core systems
Have direct influence over technical direction
Join a small, high-trust team
Own meaningful work end-to-end
Help move Hablo from legacy systems toward a stronger in-house engineering foundation
Compensation and Benefits
Competitive, location-based salary
Remote-first working
AI development tools covered where useful
Home office support
Learning and development budget
Flexible working environment
Important Note
This role is best suited to someone who enjoys improving existing systems, not someone who only wants to work on brand-new projects.
We need a developer who can understand what already exists, make it better, and help us move quickly without breaking production.
Hires remotely in
Europe
Remote work policy
Remote only
Company Location
London
Job type
Full Time
Visa sponsorship
Not Available
Preferred timezones
Coordinated Universal Time, Central European Time
Relocation
Not Allowed
Experience
5+ years