Senior Software Engineer

Who are we? At Halcyon Labs, we believe that relationships are everything in business and in life. Founded by two former CEOs of S&P 500 companies and a former presidential press secretary, our premier information service is built for developing relationships that impact decisions in government, business, and media. Utilizing deep research expertise and cutting-edge technology, we help our clients win business and influence policy across various specialties and verticals. We are a close-knit team dedicated to helping each of our users make a difference. Halcyon Labs Canada (LCC) , a subsidiary of Halcyon Labs Inc., is our Canadian entity operating in the Quebec province. This opportunity requires an applicant to live and work within the Quebec province. About the Role We’re hiring a senior full-stack engineer to make a major contribution across the LCI platform. You’ll ship features end-to-end on our Ariadne product, strengthen the shared services and libraries that every team depends on, and help shape new greenfield initiatives. The work spans backend services in Kotlin/Spring Boot, a React/TypeScript frontend, and the cloud infrastructure that ties them together. You’ll own problems from fuzzy idea to production — designing, implementing, shipping, watching them run, and iterating. Core Functions of the Role Design, build, and maintain backend services and APIs that power our customer-facing applications. Build and evolve frontend features in React/TypeScript that surface those capabilities to end users. Contribute to and improve the shared libraries (API models, auth, messaging, AWS utilities) used across our microservices ecosystem. Take on greenfield work — propose architecture, build the first version, and iterate based on real usage. Collaborate across engineering, product, and design to define requirements, iterate quickly, and deliver reliable releases. Participate in planning, design, code review, deployment, and on-call rotation using Agile practices. Propose pragmatic solutions and improvements that directly influence product direction. Required Qualifications 5+ years of professional software engineering experience building and operating production systems. Strong backend fundamentals: API design, testing, debugging, performance, and operational thinking. Production experience in Kotlin or another JVM language (Java/Scala). Kotlin strongly preferred. Production experience with Spring Boot and the broader Spring ecosystem (or demonstrated ability to ramp quickly with equivalent framework experience). Demonstrated production experience with React and TypeScript Experience working in a real microservices architecture with cross-service communication. Experience with at least one authentication/identity system (JWT, SAML/SSO, OAuth, passwordless). Experience with event-driven systems and message brokers (RabbitMQ, SQS, Kafka, or similar) and the eventual-consistency trade-offs they imply. Experience building B2B SaaS, ideally multi-tenant. Solid understanding of relational databases (PostgreSQL preferred), data modeling, and query patterns. Comfortable working in a small team with high ownership and ambiguous problems. Preferred Qualifications Experience with Redis (caching, pub/sub) in production. Experience with Elasticsearch / OpenSearch in production. Experience with Hibernate / JPA, including audit-logging frameworks (e.g., Envers). AWS depth — S3, SQS, Secrets Manager, ECS, Lambda, CloudFront. Containerized deployment experience (Docker, ECS, CI/CD). Experience with SAML2 / SSO federation (e.g., OpenAthens, Okta, Azure AD). Experience integrating LLMs or AI workflows into production applications. Experience with Gradle (Kotlin DSL) and multi-module JVM builds. What Is It Like to Work Here? We foster an environment that encourages all our team members to excel by offering competitive compensation for top talent. We believe in creating a friendly and enjoyable workplace, with regular team-building events, happy hours, and more. Transparency is key within our company, and we hold monthly town halls led by our CEO to address questions regarding business plans, product direction, and company goals. In addition, we provide flexible PTO policies to ensure you can enjoy your time outside the office and focus on your personal life. Are you ready to join our dynamic team and build meaningful relationships that make a difference? Apply today! Benefits/Rewards: Awesome Extended Health Care Plan Dental Care Life & Disability insurance Health spending accounts Unlimited Vacation Leave 12 Paid Holidays $3,000 Employee Referral Program Employer contribution to VRSP Rewards and recognition programs If you’re excited about this role but don’t meet 100% of the requirements, we still want to hear from you! Halcyon Labs is committed to building a diverse and inclusive workforce where unique experiences are valued and everyone has the opportunity to contribute. Research has continuously sh