Backend Engineer, Data Platform & APIs at Halcyon

About Us

Halcyon is the industry’s first dedicated, adaptive security platform, combining multiple proprietary prevention engines with AI models focused on stopping ransomware. Founded by cyber veterans, we build products and solutions for mid-market and enterprise customers and operate as a remote-native, distributed team.

The Role

We are hiring a mid-level Backend Engineer to join our cloud team and help develop and evolve our data platform and public API services. You will primarily work on Scala services while helping shape selective migrations to C#, and support Python-based security analysis workflows. This role contributes to ingestion, transformation, enrichment, and serving of security data that powers internal and customer-facing features.

Responsibilities

• Develop features across the data platform and public APIs, including secure ingestion, transformation, and enrichment of security telemetry.
• Collaborate on architecture and system design with product and platform engineers to align dataflow and API contracts.
• Build, test, deploy, and monitor Scala-based backend services for reliability, performance, and security.
• Support migration efforts by helping transition selected APIs from Scala to C# while ensuring continuity and consistency.
• Maintain code quality through documentation, code reviews, testing, and operational best practices.
• Participate in incidents and post-incident reviews to improve reliability and observability.
• Support Python workflows for malware analysis, automated detection, and ML model pipelines.

Skills and Qualifications

• 5+ years of backend engineering experience, with recent work in a JVM-based codebase.
• Exposure to C# or willingness to learn it as part of an API migration path.
• Strong understanding of APIs, messaging systems such as Kafka, and modern data stores like Postgres, DynamoDB, and OpenSearch.
• Experience building cloud-native services, preferably on AWS.
• Working knowledge of containers and Kubernetes for deploying services at scale.
• Comfortable in a remote-first, asynchronous team environment and experienced in design discussions and code reviews.

Bonus Skills

• Familiarity with functional programming and idiomatic Scala patterns.
• Experience with Terraform, Helm, GitHub Actions, and observability stacks like Prometheus and Grafana.
• Prior experience building security products, data pipelines, or high-availability systems.
• Python experience for security analysis and malware tooling, familiarity with ML workflows, AutoML, MLflow, or binary analysis libraries such as LIEF, ssdeep, or TLSH.

Benefits

• Comprehensive healthcare including medical, dental, and vision, with premiums paid in full for employees and dependents.
• 401(k) plan with a generous employer contribution.
• Short and long-term disability coverage, basic life and AD&D insurance, and FSA options.
• Flexible PTO policy and parental leave.
• Generous equity offering and participation in Halcyon’s equity programme.

Compensation

Base Salary Range: $120,000 - $170,000. Bonus Target: 10%. This range is a reasonable estimate and actual pay may vary based on experience, skills, and location. The role may be eligible for additional discretionary bonuses or incentives.

About the Opportunity

This is a full-time, remote position. You will join a team building scalable, maintainable backend systems that serve a global security product. If you enjoy working with Scala, cloud platforms, and Python-based security workflows, we encourage you to apply.

Apply

To apply, submit your application via the job listing. We look forward to learning how you can contribute to Halcyon’s mission to stop ransomware.