About Aries Aries is a rapidly-scaling, next-generation software group purpose-built to scale founder-led, mission-critical SaaS companies at the heart of the $50B cloud ecosystem. We unify niche B2B SaaS businesses under Aries' AI and Growth Platform - unlocking visibility, velocity, and value across our portfolio. With a permanent capital base and ~$200M invested annually, we’re building a new model for software scale focused on long-term value. The Role: Senior Software Engineer As a Senior Software Engineer on the core Aries engineering team, you’ll play a key role in designing and building the foundational systems that power our platform — enabling fast iteration, deep visibility, and scalable growth across our SaaS portfolio. This is a hands-on role for a technical builder who’s excited to solve high-leverage challenges, prototype experimental tools, and contribute meaningfully to our engineering culture. You’ll work alongside a small, senior team and collaborate closely with product, data, and AI functions. What You’ll Do: Build Core Infrastructure: Design and develop internal tools, APIs, and agents that integrate data, systems, and workflows across our SaaS group. Prototype with Purpose: Quickly turn high-level ideas into working products and iterate based on business feedback. Engineer Growth Systems: Build tools that support GTM agents, automate workflows, and enable better decision-making at scale. Collaborate Cross-Functionally: Work closely with product managers, data scientists, and AI engineers to deliver real business impact. Integrate & Stitch Systems: Connect 3rd-party APIs and internal services via clean interfaces and stateful pipelines. Champion Code Quality: Write clean, maintainable, well-tested code while mentoring others on engineering best practices. What We’re Looking For: 4 years of experience building backend systems, AI agents, APIs, or infrastructure in modern programming languages (Python, Ruby-on-Rails, TypeScript, Go, etc.) Comfortable working in fast-paced environments with shifting priorities and high autonomy Experience building integrations, internal tools, or platform services Strong product sense: you care about what you’re building and how it helps the business Solid understanding of system design, async workflows, and cloud infrastructure (bonus: experience with agent-based architectures or state machines) Enthusiastic about learning, growing, and collaborating across disciplines Why This Role? Join an elite founding engineering team with massive ownership and impact Build real systems used across a portfolio of profitable SaaS companies Work at the frontier of product, data, AI, and growth — all in one environment Help shape the culture and direction of a fast-moving, well-funded platform business Let’s Build If you’re excited by the idea of building from 0→1, solving real-world problems, and shaping a world-class engineering org — we’d love to hear from you. Apply now or reach out for an informal chat.