Senior Software Engineer

Ontik; England; On-site; GBP 125,000 - 150,000; Full time

Job summary

A B2B financial operations platform in London is seeking a Senior Software Engineer for a full-time role. The position requires 5+ years of software engineering experience, expertise in .NET and React, and a proactive attitude. This hands-on role involves building and scaling the platform, collaborating with cross-functional teams, and owning critical features. The company values a high-performance culture and offers a competitive salary with equity opportunities. Join to make a tangible impact in a fast-growing startup.

Qualifications

• 5+ years of software engineering experience, preferably in startups.
• Proficiency in .NET and React for full-stack development.
• Experience with SQL, NoSQL, APIs, and web technologies.

Responsibilities

• Build and scale financial operations platform with clean, high-performance code.
• Collaborate with product managers and designers to solve complex problems.
• Own critical features and contribute to platform architecture.

Skills

Proactive attitude

Full-stack development

Cloud platform experience

Problem-solving skills

Collaboration

Excellent communication skills

Passion for software development

Job description

Senior Software Engineer

📍 Location: Onsite, London, United Kingdom

⌛ Type: Full-time

💰 Compensation: Negotiable (Competitive salary + equity)

About Ontik

Ontik is an ambitious, early-stage B2B financial operations platform designed to streamline and simplify complex financial workflows for heavy‑duty industries. We’re scaling rapidly and looking for top‑tier engineers to join our team. You’ll have the chance to work in a high‑performance, ownership‑driven environment, where you can make a direct impact on the product and help shape its future.

Role overview

As a Software Engineer (Full‑Stack) at Ontik, you’ll play a pivotal role in building and scaling our financial operations platform. This is a hands‑on, high‑impact position where you will be directly responsible for delivering clean, scalable, and high‑performance code. You will work closely with product managers, designers, and other engineers to solve complex problems and create intuitive solutions that help simplify financial workflows for our users.

You’ll have the opportunity to own critical features and contribute to the overall architecture of our platform. We’re looking for an engineer who thrives in a fast‑paced environment, embraces ownership, and is passionate about building software that makes a real difference. If you enjoy working with cutting‑edge technologies, solving challenging problems, and iterating quickly in a collaborative environment, we’d love to hear from you.

Essential experience

• 5+ years of experience in software engineering, ideally with some experience in a startup environment.
• A proactive, ownership‑oriented attitude with the ability to take initiative and drive projects forward
• Proficiency in full‑stack development using any object‑oriented language (we use .NET) and any modern JavaScript framework (we use React)
• Experience working with databases (SQL and NoSQL), APIs, and web technologies.
• Experience with cloud platforms (AWS, GCP, Azure)
• Solid understanding of software engineering principles, including clean code, testing, and version control (git).
• Strong problem‑solving skills and the ability to break down complex technical issues and deliver simple, effective solutions.
• A collaborative mindset, with the ability to work closely with cross‑functional teams to deliver high‑quality products
• Excellent communication skills to articulate technical concepts to both technical and non‑technical team members
• A passion for building robust, efficient software and a desire to continuously improve your skills and knowledge
• Familiarity with financial technologies, payment systems, or SaaS products
• Experience with continuous integration / continuous deployment (CI / CD) pipelines

Desirable

• Experience delivering challenging integrations with 3rd party systems
• Understanding of event‑driven system design

Why Ontik?

At Ontik, we embrace a high‑performance, ownership‑driven culture where every team member plays a critical role in our success. We move quickly, take responsibility for our work, and continually strive for excellence. As a Software Engineer, you’ll have the opportunity to take ownership of key features, work with brilliant colleagues, and make a tangible impact on the future of our platform. If you’re ready to solve challenging problems, build innovative solutions, and contribute to a fast‑growing startup, Ontik is the place for you.