At a Glance
- Tasks: Own features in C# and Java, from design to production, while improving systems.
- Company: Join Threecolts, a leading software suite for top consumer brands.
- Benefits: Enjoy a £90,000 salary, 25 days PTO, and remote work options.
- Other info: Collaborative environment with opportunities for growth and innovation.
- Why this job: Make a real impact on e-commerce solutions and solve practical problems.
- Qualifications: 5–8+ years in software engineering with strong C# and Java skills.
The predicted salary is between 90000 - 90000 £ per year.
About Threecolts
Threecolts is the leading software suite for online & offline consumer brands (Amazon, Walmart, Target, Shopify, eBay, etc.). We've built a powerful ecosystem of software solutions to help businesses grow smarter — from revenue recovery and retail finance, to multichannel operations and pricing optimization. With over 500 employees globally and strong backing, we're scaling fast across new markets and new partner channels.
We're a global team built for speed, trust, and impact. As an AI enabled company, AI is integrated across Threecolts from development through to operations, empowering teams to move faster, build better, improve quality, and make more informed decisions. We hire exceptional people from all backgrounds and give them the autonomy to move fast and the accountability to deliver, where you will wear multiple hats, take ownership of challenges, and proactively solve problems beyond your immediate scope. Change is constant, ambiguity is part of the deal, and clear, concise communication is how we stay aligned, so when in doubt, bring people in.
Key Responsibilities
- Take ownership of features across Inventory Lab's C# and Java-based systems, delivering them from initial design through to production.
- Design and build clean, scalable services, APIs, and components that are maintainable, well-tested, and performant.
- Operate independently within a defined scope, making sound technical decisions and balancing speed with long-term quality.
- Play an active role in improving the systems you work on, debugging production issues, identifying root causes, and implementing durable fixes.
- Contribute to technical discussions, help evolve architecture within your domain, and raise the bar through thoughtful code reviews.
- Collaborate closely with Product, QA, and DevOps to build features and improvements that deliver meaningful value to Inventory Lab customers.
Qualifications
- 5–8+ years of professional software engineering experience.
- Strong proficiency in C# and Java.
- Experience building and maintaining backend services, APIs, and scalable application components.
- Solid understanding of REST APIs, system design, and scalable application patterns.
- Experience working with SQL databases and data modelling.
- Familiarity with cloud infrastructure, ideally AWS.
- Experience debugging production systems and resolving issues independently.
- Comfortable working with Git, code reviews, and team-based development.
- Ability to work across an existing codebase and improve quality without over-engineering.
- Strong ownership mindset and consistently deliver high-quality work.
- Make pragmatic technical decisions, understanding when to prioritise speed and when to invest in scalability, reliability, and maintainability.
- Comfortable working in a product-led environment and care about the customer impact of what you build.
- Communicate clearly, work well with cross-functional teams, and look for ways to improve both the product and how the team operates.
In this role, you'll support Inventory Lab, a product used by ecommerce sellers to manage inventory, listing, accounting, and operational workflows. The work will suit someone who enjoys solving practical product problems, improving reliability, and building systems that support real customer use cases.
Compensation, Perks & Benefits
- Salary: £90,000 per year.
- 25 days PTO.
- Opportunity to join company-wide offsites.
- Regular rate reviews and bonus opportunities.
- Fully remote/hybrid working.
Senior Software Engineer - C# / Java in London employer: Threecolts LLC
Threecolts is an exceptional employer that fosters a dynamic and inclusive work culture, empowering employees to take ownership of their projects while collaborating with talented teams across the globe. With a strong focus on professional growth, employees benefit from regular rate reviews, generous PTO, and the flexibility of remote or hybrid working arrangements, all while contributing to innovative solutions that drive success for leading consumer brands. Join us to be part of a fast-paced environment where your contributions make a real impact and where change is embraced as a pathway to excellence.
StudySmarter Expert Advice🤫
We think this is how you could land Senior Software Engineer - C# / Java in London
✨Join Local Tech Meetups
Get out there and mingle with fellow developers by joining local tech meetups. It’s a fantastic way to meet people who might be working at Threecolts LLC or know someone who does. Plus, you can pick up some trendy tech skills and trends while you're at it!
✨Contribute to Open Source Projects
Show off your coding chops by jumping into open-source projects. Not only does this give you practical experience, but it also gets you noticed in the dev community. You'll create a killer portfolio that speaks volumes about your skills to Threecolts LLC.
✨Tap into Online Developer Communities
Don’t underestimate the power of online developer communities like GitHub, Stack Overflow, and even Reddit. Participate in discussions, share your projects, and build your visibility. We can often find opportunities through these channels that can lead to a full-time gig at companies like Threecolts LLC.
✨Explore Job Boards Specifically for Tech Roles
Keep your eyes peeled on job boards that focus on tech roles. Sites like TechCareers or Stack Overflow Jobs can often have listings for companies like Threecolts LLC that might not show up on broader job sites. Make it a habit to check these regularly, and don’t hesitate to apply directly through our website!
We think you need these skills to ace Senior Software Engineer - C# / Java in London
Some tips for your application 🫡
Show off your coding skills:When applying for a software engineering role, it's super important to showcase your coding skills. Make sure your CV includes your tech stack, any relevant programming languages you’re comfortable with, and examples of projects you've worked on. If you have a GitHub profile, link it up! We love to see code in action.
Tailor your portfolio:For a full-time role, we’d expect to see some solid examples of your work in your portfolio. Make sure to include at least two or three projects that highlight your problem-solving skills and your ability to work with different technologies. Focus on the projects that are most relevant to the position at Threecolts LLC.
Craft a killer cover letter:Your cover letter is your chance to stand out—make it personal! Explain why you want to work at Threecolts LLC and how your skills align with the role. Show us your passion for software development. We dig enthusiastic candidates who understand the value of collaboration and continuous learning!
Be clear and concise:When it comes to writing your CV and cover letter, clarity is key. Avoid jargon that could confuse us and stick to simple, direct language. Highlight your achievements with quantifiable results where possible, and keep everything easy to read. A well-organised application goes a long way!
How to prepare for a job interview at Threecolts LLC
✨Brush Up on Your Coding Skills
For a full-time software engineering role, it's crucial that we stay sharp with our coding abilities. Expect technical questions that might involve solving problems on the spot or discussing algorithms. Practise on platforms like LeetCode or HackerRank to get comfortable with the types of questions that often come up.
✨Know Your Tools and Frameworks
Make sure we’re well-acquainted with the tools and technologies listed in the job description. Familiarise ourselves with any specific frameworks or programming languages mentioned. If Threecolts LLC uses React or Node.js, for instance, be ready to discuss how we’ve used them in previous projects or coursework.
✨Showcase Your Projects
Bring along a portfolio that highlights our best work. This could be code samples, GitHub repositories, or any side projects we’ve built. Make sure we can talk through our thought process for each project, especially the challenges we faced and how we solved them—this shows our problem-solving skills in action.
✨Prepare for Behavioural Questions
While technical skills are key, full-time positions also require cultural fit. Be ready to discuss our previous experiences and how we handle teamwork, conflict, and deadlines. Brush up on the STAR method—Situation, Task, Action, Result—to clearly articulate our past experiences when discussing how we've contributed to a team.
