Full Stack Developer (Mid-Level / Senior)

Avacone; Basel; On-site; CHF 120,000 - 180,000; Full time

Job summary

Avacone is seeking a Full Stack Developer to design, build, and maintain web applications for a banking client. You will work across frontend, backend, and data layers, collaborating with delivery teams and stakeholders to deliver secure, reliable software.

We’re hiring at mid-level and senior levels; your level reflects the scope of work and technical leadership you’ve demonstrated. On-site in Basel, with modern tech stack exposure.

Qualifications

• Production web apps experience across frontend, backend.
• Strong JS/TS and a modern frontend framework (React/Angular/Vue).
• REST APIs with Java/.NET/Node.js/Python.
• SQL and relational database expertise.
• Git, code reviews, tests, and CI/CD experience.
• Ability to diagnose issues across the stack using logs and tools.
• Understanding of secure development practices and data handling.
• Clear communication of technical decisions.

Responsibilities

• Design, develop, and maintain web apps, APIs, and data models in a banking environment.
• Clarify business requirements with client stakeholders and break work into testable increments.
• Write maintainable code, automated tests, review PRs, document decisions.
• Follow security, data protection, and change management processes.
• Support deployments, troubleshoot production issues, and improve performance.

Skills

JavaScript/TypeScript

React/Angular/Vue

REST APIs

Java

Node.js

Python

SQL

Git & CI/CD

Security best practices

Communication

Tools

CI/CD tools

Monitoring tools

Logging/Observability

Job description

About the role

We are an IT services company looking for a Full Stack Developer to build and maintain applications for one of our banking clients. You’ll work across the frontend, backend, and data layers, collaborating with our delivery team and the client’s business and technology stakeholders. You’ll take features from requirements through production and help ensure the applications are secure, reliable, and maintainable.

We’re hiring at both mid-level and senior level. Your level will reflect the scope and complexity of the work you’ve owned and the technical decisions you’ve led.

Responsibilities

• Design, develop, and maintain web applications, APIs, and data models in a banking environment.
• Work with client stakeholders and the delivery team to clarify business requirements, define acceptance criteria, and break work into increments that can be tested and released independently.
• Write maintainable code and automated tests, review pull requests, and document technical decisions and operational procedures.
• Follow the client’s security, data protection, and change management processes throughout development and release.
• Support deployments, troubleshoot production issues, and improve application performance and reliability.

Responsibilities

• Design, develop, and maintain web applications, APIs, and data models in a banking environment.
• Work with client stakeholders and the delivery team to clarify business requirements, define acceptance criteria, and break work into increments that can be tested and released independently.
• Write maintainable code and automated tests, review pull requests, and document technical decisions and operational procedures.
• Follow the client’s security, data protection, and change management processes throughout development and release.
• Support deployments, troubleshoot production issues, and improve application performance and reliability.

Required for both levels

• Professional experience building and maintaining production web applications, with hands-on contributions to frontend and backend development.
• Proficiency in JavaScript or TypeScript and experience with a modern frontend framework such as React, Angular, or Vue.
• Experience building and integrating REST APIs with a backend technology such as Java, .NET, Node.js, or Python.
• Working knowledge of SQL and relational databases, including data modeling and query troubleshooting.
• Experience with Git, code reviews, automated testing, and CI/CD workflows.
• Ability to diagnose issues across the stack using logs, monitoring tools, and debuggers.
• Understanding of secure development practices, including input validation, authentication, authorization, and the handling of sensitive data.
• Ability to communicate technical decisions clearly to engineers and business stakeholders.

Mid-Level

• Experience independently implementing, testing, and releasing well-defined features across the stack.
• Ability to clarify requirements, contribute to technical design discussions, and raise risks and dependencies early.

Senior

• Experience leading the technical design and delivery of complex features or systems through production rollout.
• Ability to evaluate architectural trade-offs, document decisions, and explain their implications to client stakeholders.
• Experience coordinating technical dependencies across teams and mentoring engineers through design discussions, pairing, or code reviews.

Preferred qualifications

• Experience in banking, financial services, or another regulated industry.
• Familiarity with audit logging, access controls, or formal change management processes.
• Experience integrating applications with enterprise systems or third-party services.
• Experience with cloud platforms, containers, or infrastructure as code.