Senior Backend Cloud Engineer.

What we do:
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.

Who we are:
Halcyon was formed in 2021 by a team of cyber industry veterans after battling the scourge of ransomware (and advanced threats) for years at some of the largest global security vendors. Comprised of leaders from Cylance (now Blackberry), Accuvant (now Optiv), Fireye and ISS X-Force (now IBM), Halcyon is focused on building products and solutions for mid-market and enterprise customers.

As a remote-native, completely distributed global team, we recognize great talent can exist anywhere. We invite you to apply to a job you’re interested in and we'll work a plan to meet your needs.

The Role  

  

At Halcyon, we’re building a world-class anti-ransomware platform grounded in innovation and resilience. As part of that vision, we’re looking for a Senior Backend Engineer to join our cloud team. You’ll lead the development and evolution of our data platform and API services, working within a modern tech stack that blends 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.  

Skills and 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 Skills and 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. 

In accordance with applicable state and federal laws, the range provided is Halcyon’s reasonable estimate of the base compensation for this role. The actual amount may differ based on non-discriminatory factors such as experience, knowledge, skills, abilities, and location. Base pay is one part of the total package that is provided to compensate and recognize employees for their work, and this role may be eligible for additional discretionary bonuses/incentives, and equity in the Company.

We understand it takes a diverse team of highly intelligent, passionate, curious, and creative people to develop the exceptional product we are building. Our dynamic team has incredible perspectives to share, just as we know you do, and we take great pride in being an equal opportunity employer.