Senior Software Engineer – Full-Stack & Cloud Infrastructure

Senior Software Engineer - Full-Stack & Cloud Infrastructure

Were looking for a senior engineer who likes owning things end to end.

• Take an idea from a whiteboard to a working proof of concept then through to a production system that people depend on.
• Move between rapid prototyping and production hardening as needed.
• Own infrastructure CI/CD observability and security alongside application development.
• Work directly with leadership in an environment with no separate DevOps handoff.

• Spec-driven development - write requirements design API contracts data models and correctness properties before coding.
• Rapid prototyping - turn a business idea into a working proof of concept quickly while keeping it structured enough to scale.
• Production delivery - harden prototypes provision infrastructure build pipelines promote through Dev QA Staging and Production and maintain stability after launch.
• Backend services - build REST APIs background workers data pipelines and integrations with Microsoft 365 Salesforce AI/LLM providers and payment systems.
• Cloud infrastructure - manage AWS resources written as Terraform across multiple environments.
• CI/CD pipelines - build automated build test scan deploy and rollback workflows.
• AI and LLM integrations - connect LLM APIs into product workflows including prompt design structured output handling confidence scoring and cost tracking.
• Agentic AI systems - design AI agents with multi-step reasoning tool use structured outputs human-in-the-loop checkpoints and graceful handling of uncertainty.
• Observability - implement structured logging custom metrics health checks and alerting.
• Frontend - work with React or TypeScript-based frontends as needed.

This is what the day-to-day work actually looks like so be honest with yourself about whether it fits.

• Backend: Strong in at least one backend language - Python or - and able to pick up the other when needed. Able to write production-grade code with async patterns strong typing explicit error handling structured logging and stable REST APIs with proper HTTP semantics and server-side auth enforcement.
• AWS: Experience provisioning and operating ECS Fargate RDS ALB ECR IAM Secrets Manager and CloudWatch in production. Able to manage Terraform with proper environment separation remote state and module structure.
• Containers and CI/CD: Experience building production Docker images with multi-stage builds non-root users health checks and image scanning plus CI/CD pipelines in GitLab CI or GitHub Actions with automated deployment rollback and no long-lived credentials.
• Agentic AI: Understands tool-calling or function-calling workflows structured prompting uncertainty handling and human-in-the-loop design especially in high-stakes environments like payments. Experience with LangChain LlamaIndex Strands or custom agent loops is relevant.
• Security: Comfortable with parameterized queries secrets managers least-privilege IAM and input validation at the API boundary.
• Testing: Writes meaningful unit integration and property-based tests that catch real regressions.
• Nice to have: Datadog APM and custom metrics enterprise OAuth2 integrations such as Microsoft Graph and Salesforce LLM API experience with Anthropic or OpenAI and OIDC-based CI/CD auth to AWS.

• Work spec-first by writing requirements designing solutions and agreeing on the approach before major feature development.
• Contribute directly to design docs and correctness thinking rather than only implementing handed-off work.
• Thrive in a small high-trust team with direct communication low ceremony and high autonomy.
• Raise concerns early give honest feedback and collaborate closely with leadership and teammates.
• Care about both speed and quality with a focus on software that works well and avoids future problems.
• Speak up when something should be done differently because individual opinions have real weight on a small team.

• Employment Type: Contract-to-hire
• Experience: 7 years in a professional software engineering role
• Location: Hybrid NYC based
• Compensation: Competitive based on experience