Senior Backend Cloud Engineer - Halcyon

About Halcyon

Halcyon is the industry’s first dedicated, adaptive security platform that combines multiple proprietary advanced prevention engines along with AI models focused specifically on stopping ransomware.

Formed in 2021 by cyber industry veterans from Cylance, Accuvant, FireEye, and ISS X-Force, Halcyon builds products and solutions for mid-market and enterprise customers. We are a remote-native, completely distributed global team that recognizes great talent can exist anywhere.

The Role

At Halcyon, we’re building a world-class anti-ransomware platform grounded in innovation and resilience. We are looking for a Senior Backend Engineer to join our cloud team to lead the development and evolution of our data platform and API services, working within a modern tech stack blending Scala and Rust.

You’ll join a team focused on building scalable, maintainable backend systems that serve both internal and customer-facing functions. Your primary focus will be on Rust and Scala services, with opportunities to shape our transition to Rust where it makes sense. Python development experience is highly valued, particularly for supporting our security analysis platform which includes malware analysis engines, automated threat detection, and machine learning workflows.

Responsibilities

• Lead the design and delivery of features across our data platform and public API services, including ingestion, transformation, and enrichment of security data.
• Drive system design, architecture, and data flow decisions in partnership with product and platform engineering.
• Build, deploy, and own Scala-based backend services in production, keeping them reliable, secure, and performant.
• Help shape and execute our migration of selected APIs from Scala to Rust, ensuring consistency and continuity along the way.
• Set the bar for code quality, documentation, and operational excellence.
• Lead design reviews, code reviews, and take part in on-call and incident response.
• Support and enhance our Python-based security analysis platform, including malware analysis engines, automated threat detection, and machine learning model workflows.

Qualifications

• 5+ years of backend engineering experience, with recent experience in a JVM-based codebase.
• A track record of designing and owning distributed systems from start to finish.
• Experience with Rust, or a well-formed view of when it’s the right tool, and the ability to help guide a migration.
• Strong understanding of APIs, messaging systems (Kafka), and modern data stores (Postgres, DynamoDB, OpenSearch).
• Experience building services in a cloud-native environment, preferably AWS.
• Working knowledge of containers and Kubernetes.
• Comfortable working in a remote-first, asynchronous team environment.

Bonus Qualifications

• Familiarity with functional programming patterns and idiomatic Scala.
• Experience with Databricks and ClickHouse (or similar lakehouse and analytical/OLAP data stores).
• Experience with Terraform, Helm, and GitHub Actions.
• Familiarity with observability tools (Prometheus, Grafana, CloudWatch).
• Prior work on security products, data pipelines, or high-availability systems.
• Python development experience, particularly with security analysis tools and malware detection frameworks (YARA, PE analysis, binary analysis).
• Familiarity with machine learning workflows, AutoML, and MLflow for model deployment and management.
• Experience with binary analysis libraries (LIEF, ssdeep, TLSH) and security tooling integration.

Benefits & Compensation

• Base Salary Range: $120,000 - $170,000 (Base pay estimate based on experience, location, and skills)
• Bonus Target: 10% target bonus + generous company equity offering
• Healthcare: Comprehensive medical, dental, and vision with premiums paid in full for employees and dependents
• Retirement: 401(k) plan with generous employer contribution
• Insurance: Short & long-term disability, basic life, and AD&D coverage
• Flexible Spending: Medical and dependent care FSA options
• Time Off: Flexible PTO policy + paid parental leave