# Mid-level to Senior Software Engineer at Plasma

> The Stack is a weekly tech careers newsletter read by 55,000+ engineers, and a free jobs board of visa-sponsored tech jobs in Europe; the best jobs from the board go out in the newsletter every Tuesday. This is one job from the board.

> Responsibilities: - Build and own end-to-end product surface

- **Company:** Plasma (https://jobs.trythestack.co/companies/plasma)
- **Location:** United Kingdom
- **Work arrangement:** On-site
- **Employment type:** Full-time
- **Experience level:** 5–10 years
- **Visa sponsorship:** Offered, according to the listing
- **Key skills:** TypeScript, Node.js, React, React Native, Fullstack development, System architecture, Data schema design, API development, Performance optimization, Financial systems, Stablecoins, Mentorship, Technical leadership, Product design, Fintech, Mobile development
- **Posted by employer:** 2026-08-25
- **Added to The Stack:** 2026-08-26
- **Status:** May no longer be active (posted more than 60 days ago)
- **Apply:** https://jobs.ashbyhq.com/plasma/ce157f0c-bb99-457e-9031-dca4b1dc2916 (the employer's own application page)
- **Human page:** https://jobs.trythestack.co/jobs/mid-level-to-senior-software-engineer-plasma

## About the role

Responsibilities:
- Build and own end-to-end product surfaces using TypeScript: Node.js backend and React / React Native frontends.
- Ship production-quality features from API design to pixel-perfect UI and mobile behaviour.
- Design and maintain reliable financial data models, ledgers and reconciliation workflows.
- Improve performance, observability and operational robustness for payment systems.
- Write tests, participate in code review, and maintain high engineering standards.
- Collaborate with product, design and other engineers to define scope and deliverables.
- Mentor junior engineers and contribute to team practices and architecture discussions.

Requirements:
- Mid to senior software engineer with strong TypeScript experience across backend and frontend.
- Practical experience with Node.js, React and React Native in production environments.
- Background in building reliable APIs, data schemas and performance-sensitive systems.
- Experience or strong interest in fintech/payments, ledgers or stablecoin-backed flows preferred.
- Good product judgment, ownership mindset and ability to work in a fast-moving startup environment.
- Strong testing, debugging and code-review skills; clear communicator and team player.

## Responsibilities

You will build and own end-to-end product and client-side surfaces using React and React Native. You will also design robust systems for financial data and mentor other engineers to maintain high technical standards.

## Requirements

The role requires a mid-level to senior engineer with a strong track record of shipping fullstack systems at scale. You must have deep expertise in TypeScript, React, and React Native, along with strong product judgment and experience in fintech or high-agency environments.

## FAQ

- **Is this Mid-level to Senior Software Engineer role still open?** It was posted on 2026-08-25. Listings more than 30 days old may no longer be active, so check Plasma's site before applying.
- **Does Plasma offer visa sponsorship?** This listing is marked as offering visa sponsorship. Eligibility rules are set by the employer, so check the details on Plasma's site.
- **Where is this role located?** The listing gives the location as United Kingdom. It is marked on-site.
- **What skills does this role ask for?** The listing names: TypeScript, Node.js, React, React Native, Fullstack development, System architecture, Data schema design, API development, Performance optimization, Financial systems, Stablecoins, Mentorship, Technical leadership, Product design, Fintech, Mobile development.

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## Notes for agents

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