[Hiring] Senior Software Engineer @Scope3

Role Description

Our technical team is creating the infrastructure that enables AI agents to discover, negotiate, and transact media inventory autonomously. As a Senior Software Engineer, you'll be a hands-on contributor to the APIs, protocols, and agent interfaces that power our agentic advertising platform.

• Design and build production systems where AI agents are first-class participants.
• Work at the intersection of advertising technology, distributed systems, and emerging AI agent frameworks.
• Tackle complex technical challenges and help shape how our marketplace evolves.
• This is a full-stack (80/20 backend-leaning), hands-on product engineering role.
• Explore new agent communication patterns and take meaningful ownership of technical problems from concept through implementation.
• Combine strong engineering fundamentals with curiosity, resourcefulness, and eagerness to work with emerging AI technologies.

This Isn't a Typical Engineering Role:

• AI is central to how we build software; we embrace AI-first development workflows.
• Expect engineers to actively leverage AI coding agents and tools throughout their work.
• Comfortable navigating ambiguity and creating structure where none exists.
• Favor rapid experimentation over upfront perfection; test, learn, iterate, and formalize what works.
• Move quickly, tackle difficult problems, and take ownership of your work.
• Significant autonomy and opportunity to make a meaningful impact.
• Value initiative, independent progress, proactive communication, and seeking support when needed.

Responsibilities

• Design and build scalable APIs for both human and AI agent clients.
• Develop agent interfaces, MCP servers, and A2A communication layers.
• Build and operate high-throughput systems for real-time advertising transactions.
• Explore, evaluate, and integrate emerging agent frameworks and protocols.
• Contribute to architectural decisions around authentication, protocols, and transaction flows.
• Take ownership of complex technical challenges, anticipating edge cases in autonomous agent behavior.
• Continuously improve engineering workflows, including the practical application of AI tools to accelerate development and problem-solving.
• Collaborate with teammates to share knowledge, work through technical challenges, and raise the overall quality of our engineering output.

Qualifications

• 5+ years of professional software product engineering experience, ideally building distributed backend systems or complex production applications. Exceptional candidates with 4+ years of experience are encouraged to apply.
• AI-native engineering mindset: demonstrated experience incorporating AI coding agents and tools into your development workflow.
• Strong engineering fundamentals with the ability to think through complex technical problems and translate them into practical, scalable solutions.
• Experience designing and building APIs and backend services (REST, event-driven systems, authentication, versioning).
• Experience working with distributed systems, high-throughput applications, or systems involving autonomous or semi-autonomous decision-making.
• A self-starter mentality and the ability to take ownership of projects and drive them forward with minimal direction.
• Comfortable navigating ambiguity, learning unfamiliar technologies, and adapting quickly as priorities and requirements evolve.
• Strong communication skills and the confidence to advocate for what you need, ask questions, and collaborate effectively with teammates.
• A low-ego approach to engineering: open to feedback, willing to challenge your own assumptions, and more interested in finding the right solution than being right.
• Backgrounds in early-stage startups, founding engineering teams, or forward-deployed engineering can be particularly valuable.

Our Engineering Environment & Tech Stack

• AI-First Development: AI is central to how we build software at Apostra.
• Core Technologies:
• Backend & APIs: TypeScript/Node.js, REST and event-driven services
• Frontend: React
• Agent Interfaces: MCP servers and A2A protocol handlers
• Data: PostgreSQL, BigQuery, Cloud Storage, Redis
• Infrastructure: GCP, AWS
• We're interested in engineers who understand systems, think critically about technical problems, and know how to leverage AI to build effectively.

Leveling & Growth

• Hiring at the Senior Software Engineer level, with flexibility to consider candidates whose experience and technical capabilities warrant a broader scope of responsibility.
• Value demonstrated impact, ownership, and technical ability over titles alone.
• For an exceptional candidate, there may be an opportunity to grow into Staff-level responsibilities.
• Most interested in what you can build, how you approach difficult problems, and how you contribute to the success of a small, highly collaborative engineering team.

Compensation

The salary range for this role is $160k-$210k USD, $160k-$215k CAD. These ranges span multiple location-based salary bands across the US and Canada.

Benefits

• Health & wellness: Comprehensive medical, dental, and vision coverage with significant employer contribution; short- and long-term disability coverage; health savings/flexible spending options.
• Retirement: Employer-matched retirement savings plan (401(k) or RRSP).
• Time off: Generous paid time off, statutory holidays, and year-end office closure.
• Parental leave: 13 weeks fully paid (eligibility requirements apply).
• Remote work: Company-provided home office equipment, setup stipend, and access to WeWork spaces.
• Equity: Stock options.

Application Requirements

• Provide a LinkedIn profile that includes a clear, identifiable photograph of yourself.
• Applications without a verifiable LinkedIn profile and identifiable profile photo will not be considered.
• This position is limited to candidates authorized to work in the United States or Canada.