Senior Software Engineer (AI)

Location: Remote in the United States or Canada. Limited to candidates authorized to work in the United States or Canada; employer-sponsored work authorization is not available.

Salary: $160,000–$210,000 USD or $160,000–$215,000 CAD annually, with location-based salary bands.

Company

Apostra is building an AI-native advertising marketplace where advertisers, media owners, and AI agents can discover, negotiate, and transact media inventory.

What you will do

• Design and build scalable APIs for 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.
• Evaluate and integrate emerging agent frameworks and protocols.
• Contribute to architecture for authentication, protocols, and transaction flows.
• Own complex technical challenges, improve engineering workflows, and apply AI tools to development and problem-solving.

Requirements

• 5+ years of professional software product engineering experience, ideally with distributed backend systems or complex production applications; exceptional candidates with 4+ years may apply.
• AI-native engineering mindset with demonstrated use of AI coding agents and tools in development workflows.
• Strong engineering fundamentals and ability to translate complex problems into scalable solutions.
• Experience designing and building APIs and backend services, including REST, event-driven systems, authentication, and versioning.
• Experience with distributed systems, high-throughput applications, or autonomous and semi-autonomous decision-making systems.
• Ability to take ownership, work independently, navigate ambiguity, learn unfamiliar technologies, and adapt quickly.
• Strong communication, collaboration, self-direction, and low-ego approach to engineering.

Nice to have

• Background in early-stage startups, founding engineering teams, or forward-deployed engineering.
• Experience working directly with customers or external partners.
• Experience with TypeScript, Node.js, React, PostgreSQL, BigQuery, Cloud Storage, Redis, GCP, AWS, MCP servers, or A2A protocol handlers.
• Potential to grow into Staff-level technical responsibilities.

Culture & Benefits

• AI-first development environment with active use of AI coding agents throughout the software lifecycle.
• Small, collaborative team with autonomy, rapid experimentation, proactive communication, and ownership.
• Medical, dental, vision, disability, health savings or flexible spending coverage, with details varying by location.
• Employer-matched 401(k) or RRSP, generous paid time off, statutory holidays, and year-end office closure.
• 13 weeks of fully paid parental leave, subject to eligibility requirements.
• Remote-work equipment, home-office setup stipend, WeWork access, and stock options.

Hiring process

• Applications must include an accessible, verifiable LinkedIn profile with a clear, identifiable photograph. Applications without these details will not be considered.