Founding Engineer (Client-Embedded, Full Stack)

Who we are
3KTree is a custom software development company headquartered in Columbia, SC. Since 2017, we have partnered with stakeholders across industries to deliver innovative solutions that drive business growth. We build design systems, responsive and progressive web applications, native and cross-platform mobile apps, and AI-infused integrations using technologies like Angular, React, Vue, ASP.NET, Flutter, and React Native. We partner with fast-growing technical companies as an embedded extension of their engineering teams, helping them scale their platforms, ship faster, and solve their hardest technical problems.

Who you are
3KTree is looking for a talented, driven Founding Engineer to embed directly within one of our fast-growing client's engineering teams. We care more about your skills, communication, and hunger to build than your years on a resume. If you are a sharp full stack engineer who learns fast, communicates clearly, and wants your work to directly shape a growing company's product and trajectory, this is for you.

About the role
As a Founding Engineer collaborating with our client's team, you will work side-by-side with their engineering and product leadership. You will not be an outside contractor handing off tickets, but a trusted technical contributor helping build their product from the ground up. Because the client is itself a fast-growing technical company, the pace is high, ownership is real, and your contributions will have direct, visible impact on their growth. You will be shipping core features, building foundational systems, and helping shape technical decisions early. This role requires excellent spoken and written English, as you will be operating as a near-permanent member of the client's team in planning sessions, architecture discussions, and day-to-day collaboration. Success in this role means earning trust quickly, taking ownership beyond your task list, and becoming someone the client's team genuinely wants to keep building with.

We look for people who are
Resourceful: who can pick up new stacks and problems quickly without hand-holding
Communicative: who keep both client and 3KTree stakeholders aligned
Accountable: who own outcomes, not just tasks

Responsibilities

Client Embedding and Collaboration
- Operate as a Founding Engineer embedded directly within the client's engineering team, contributing to early architecture and product decisions
- Help build core product features and systems from the ground up alongside the client's founding/early team
- Participate in the client's standups, planning sessions, and technical discussions as a core team member, not an outside vendor

Full Stack Development
- Design, build, and maintain front-end and back-end systems that support the client's rapid growth
- Build and iterate quickly on APIs and services as product requirements evolve
- Make pragmatic technical decisions under real startup and growth-stage pressure, balancing speed and quality

Security and Performance
- Build and operate within high-speed, secured network environments, applying secure coding and data-handling practices appropriate to the client's industry
- Identify and resolve performance bottlenecks as the product scales
- Implement solid authentication, authorization, and data protection practices from day one

Direct Business Impact
- Tie technical decisions to business outcomes, understanding how your work directly affects the client's user growth, product stability, and speed to market
- Bring creative, scrappy problem solving to ambiguous or fast-evolving requirements typical of an early, high-growth company

Required Qualifications
- Strong full stack development skills in front-end (e.g., React, Vue, Angular) and back-end (e.g., Node.js, .NET, or similar)
- Excellent verbal and written English communication skills, able to operate confidently as a trusted technical voice within a client's team
- Ability to design and build RESTful APIs
- Working knowledge of cloud platforms (AWS, Azure, or GCP) and secure network environments
- Self-driven, resourceful, and comfortable learning new stacks and tools quickly
- Creative problem solver who thrives in fast-paced, high-growth, high-ownership environments
- Strong collaboration skills and ability to work autonomously with minimal oversight

Preferred Qualifications
- Any prior experience contributing to an early-stage or fast-growing tech company or startup
- Familiarity with CI/CD pipelines, Docker, Kubernetes, and infrastructure-as-code
- Exposure to fintech, SaaS, or other fast-scaling verticals
- Agile and Scrum experience
- A personal project, open-source contribution, or portfolio that demonstrates initiative and technical range