Senior Software Engineer (Full-Stack)-Copenhagen, Denmark

Agsweltgermany; København; Hybrid; DKK 900,000 - 1,200,000; Full time

Job summary

Signifly in Copenhagen is seeking a Senior Software Engineer (Full-Stack) to join its Tech team. You will work across frontend and backend services, building AI-powered features and agentic integrations while owning architecture decisions and project direction.

Required are senior full-stack experience and strong skills in TypeScript, Next.js/React, and Node.js. AI-assisted development and client-facing ownership are emphasized.

Qualifications

• Solid experience as a senior full-stack developer.
• Strong skills in modern TypeScript, Next.js/React and backend development.
• Experience with Node.js, APIs and databases.
• Hands-on experience with AI-assisted and agentic development.
• Experience with Claude Code or similar tools.
• Curiosity about AI-assisted and agentic development.
• Experience building AI-native APIs and product features is a plus.
• Ability to understand client problems and propose technical solutions.
• Ability to support clients, PMs, developers and sales teams.
• Ability to take ownership of code and projects.

Responsibilities

• Take technical ownership of client projects and architecture decisions.
• Provide technical direction and ensure development quality.
• Collaborate with frontend, backend, and product teams to deliver features.
• Share knowledge and mentor peers to grow the team.

Skills

Senior full-stack

TypeScript

Next.js/React

Node.js

APIs & databases

AI-assisted development

Agentic development

Claude Code

Client problem solving

Project ownership

Tools

Claude Code

Job description

Job Description

Signifly is looking for a Senior Software Engineer (Full-Stack) to join its Tech team in Copenhagen. The role focuses on developing digital products with clients and working across frontend, backend services, APIs, and integrations. The core technology stack includes TypeScript, Next.js, and React, with backend development using Node.js, APIs, and databases.

The position places a strong focus on AI-assisted and agentic software development. Responsibilities include using AI coding agents in daily development, building AI-powered features and agentic systems such as MCP/LLM integrations and automations, and sharing technical knowledge with the wider team. The engineer will also take technical ownership of client projects, including architecture decisions, technical direction, and development quality.

Applicants should have solid senior-level full-stack development experience and strong skills in modern TypeScript, Next.js/React, and backend development. Hands-on experience with AI-assisted and agentic development is expected, while experience building AI-native APIs and product features is a plus. The role also requires the ability to understand client problems, propose technical solutions, support colleagues and clients, and take ownership of projects and professional development.

The position is full-time and based in Signifly's centrally located Vesterbro office.

Requirements

• Solid experience as a full-stack developer in a similar senior position
• Strong skills in modern TypeScript, Next.js/React and backend development
• Experience with Node.js, APIs and databases
• Hands-on experience with AI-assisted and agentic development
• Experience with tools like Claude Code or similar
• Curiosity about AI-assisted and agentic development
• Experience building AI-native APIs and product features is a big plus
• Ability to understand real-world client problems and propose technical solutions
• Ability to support clients, project managers, developer colleagues and the sales team
• Ability to take ownership of code and projects
• Willingness to contribute to the growth of people around you