Junior / Intermediate Developer

United States Digital Space LLC; Greater London; On-site; GBP 40,000 - 50,000; Full time

Benefits offered by this job

Casual dress

Company pension

Central London office in Kings Cross /

Job summary

United States Digital Space LLC in London is seeking an intermediate software developer to join our engineering team. You will work across the full stack, including Next.js front ends, Fastify APIs, PostgreSQL and Prisma data models, and AWS Lambda background jobs.

This hands-on role gives you ownership of features from database schema through to UI, with code reviews from senior engineers and exposure to a broad stack. Clear written communication is important as we operate across time zones.

Qualifications

• 2 to 4 years of commercial software development experience.
• Strong TypeScript and JavaScript capabilities.
• Solid React experience with Next.js or a similar SSR framework.
• Experience building Node.js backend services and REST APIs.
• Comfortable with Git, PRs and code reviews.
• Able to write tests for own work.
• Clear written and spoken communication across time zones.
• Available to work full-time from Kings Cross / Camden office.

Responsibilities

• Build features across Next.js applications (admin shell, procurement, HR, commercial).
• Design REST endpoints in Fastify microservices with typed schemas.
• Model data in PostgreSQL via Prisma, extending a multi-tenant schema.
• Write AWS Lambda functions for background processing (invoice OCR and matching, PO validation, etc.).
• Integrate third party services including Stripe, Microsoft Graph, Pusher and Twilio.
• Work on AI assisted features such as document data extraction and invoice matching.
• Write unit, integration and end-to-end tests in Jest.
• Review code from across the team and contribute to internal packages.

Skills

TypeScript

JavaScript

React

Next.js

Node.js

SQL

Testing

Git

Communication

Tools

Prisma

PostgreSQL

Fastify

Job description

About us

StoneRise builds a multi-tenant ERP platform for the [construction / built environment] sector. It is a single product suite covering procurement, HR, commercial management, subcontractor payments, site management, health and safety, and training, used daily by teams running live projects.

You would be joining a mixed engineering team of onshore developers based in our London office and offshore developers working alongside us.

This is an office based role at our Kings Cross / Camden office, five days a week.

The role

We are looking for an intermediate developer to join our engineering team. You will work across the full stack, covering Next.js front ends, Fastify APIs, PostgreSQL and Prisma data models, and AWS Lambda background jobs.

This is a hands on role for someone comfortable owning a feature from database schema through to UI. You will get plenty of ownership, code review from senior engineers, and exposure to a broad stack.

As we work across time zones, clear written communication is important. That means good pull request descriptions, clear tickets, and flagging blockers early.

What you will be working on

• Building features across our Next.js applications (admin shell, procurement, HR, commercial) using the App Router, React and our shared component library


• Designing and building REST endpoints in our Fastify microservices with typed request and response schemas


• Modelling data in PostgreSQL via Prisma, extending a large multi-tenant schema


• Writing AWS Lambda functions for background processing, including invoice OCR and matching, purchase order validation, quotation matching, inbound email processing, accounting sync, and scheduled notifications


• Integrating third party services including Stripe for billing, accounting systems, Microsoft Graph, Pusher for real time updates, and Twilio


• Working on AI assisted features such as document data extraction and invoice matching


• Writing unit, integration and end to end tests in Jest


• Reviewing code from across the team and contributing to the shared internal packages used throughout the platform

Tech stack

Language and tooling

• TypeScript


• Node.js 24


• Turborepo monorepo with Yarn 4 workspaces


• ESLint, Prettier


• GitHub Actions for CI/CD across dev, test, staging and production

Front end

• Next.js 14 (App Router)


• React 18


• Tailwind CSS


• TanStack Query


• Shared in-house component library


• Heroicons


• PDF generation and preview, spreadsheet import and export

Back end

• Fastify 5 microservices with TypeBox schema validation


• Next.js API routes as a BFF layer


• JWT based authentication with role and permission based authorisation


• Multi-tenant architecture with tenant level data isolation

Data and infrastructure

• PostgreSQL


• Prisma ORM


• Redis (ioredis)


• BullMQ for job queues


• AWS Lambda, S3, SQS, SNS, DynamoDB, CloudWatch, CloudFront


• LocalStack and Docker for local development

AI and integrations

• Anthropic SDK and an in-house AI service layer


• Stripe


• Microsoft Graph


• Pusher


• Twilio


• Nodemailer


• Accounting system integrations

Quality and monitoring

• Jest for unit, integration, end to end, performance and security tests


• Sentry for error monitoring


• Structured logging


• OpenAPI and Apidog for API documentation

What we are looking for

Essential

• 2 to 4 years of commercial software development experience


• Strong TypeScript and JavaScript


• Solid React experience, and experience with Next.js or a similar SSR framework


• Experience building Node.js back end services and REST APIs


• Working knowledge of relational databases and SQL, ideally with an ORM such as Prisma, TypeORM or Drizzle


• Comfortable with Git, pull requests and code review


• Able to write tests for your own work


• Clear communicator in writing as well as in person, as you will be working daily with colleagues in other time zones


• Able to work full-time from our Kings Cross / Camden office

Desirable

• Strong understanding and experience using AI assisted coding such as Cursor


• Fastify, Express or NestJS


• AWS services, particularly Lambda, S3 and SQS


• Monorepo tooling such as Turborepo or Nx, or Yarn and pnpm workspaces


• Redis, message queues or other background job systems


• Tailwind CSS


• Multi-tenant SaaS


• Working with LLM APIs or AI assisted product features


• CI/CD pipelines and GitHub Actions


• Experience working in a distributed or partly offshore team


• Exposure to ERP, finance or construction software

What we offer

• £40,000 to £50,000 depending on experience


• Central London office in Kings Cross / Camden


• 20 days annual leave + public holidays + company Christmas/New Year shut down


• Company pension scheme


• Ownership of features from design through to production


• Broad exposure across front end, back end, cloud infrastructure and AI features


• Mentoring from senior engineers and a clear path to senior

Pay: £40,000.00-£50,000.00 per year

Benefits:

• Casual dress


• Company pension

Work Location: In person