Senior Software Engineer, Content Cards

At Halcyon Labs, we have found our people. We’re a genuinely approachable, exceptionally kind, and intensely passionate crew. We seek to ignite that passion by setting high standards, championing teamwork, and creating work-life harmony as we collectively navigate rapid growth on a global scale while striving for greater equity and opportunity – inside and outside our organization. To flourish here, you must be prepared to set a high bar for yourself and those around you. There is always a way to contribute: Acting with autonomy, having accountability and being open to new perspectives are essential to our continued success. Our deep curiosity to learn and our eagerness to share diverse passions with others gives us balance and injects a one-of-a-kind vibrancy into our culture. If you are driven to solve exhilarating challenges and have a bias toward action in the face of change, you will be empowered to make a real impact here, with a sharp and passionate team at your back. If Halcyon Labs sounds like a place where you can thrive, we can’t wait to meet you. WHAT YOU’LL DO We’re looking for a Senior Software Engineer to join our Content Cards team, which is focused on transforming in-product surfaces into dynamic, personalized experiences that adapt to user behavior in real time. We build the systems that power in-app engagement across customers’ websites and applications—covering message definition, composition, targeting, delivery semantics, and analytics—along with a feature-rich dashboard that lets brands and UX teams seamlessly manage in-product messaging experiences inside their products. As a senior engineer on the team, you will build new capabilities, improve reliability and performance, and help guide key architectural decisions as we scale. You’ll help drive ambitious initiatives that expand what customers can build on high-value surfaces, unlock new ways to present and orchestrate content, and strengthen platform foundations that accelerate future innovation across in-product channels. We value engineers who consistently raise the bar through strong technical leadership, thoughtful system design, and clear communication. WHO YOU ARE 7+ years of full-stack development experience An experienced technical leader with a track record of driving complex projects from ambiguity to delivery Strong understanding of system design, data structures, and algorithms A self-starter with strong communication and organizational skills; experienced working in a team environment Bonus: Professional experience building software at immense scale, especially customer-facing platforms with high reliability requirements Professional Experience with Ruby, Sidekiq, TypeScript/JavaScript, and React Experience with agile development processes For candidates based in Ontario, the pay range at the start of employment for this position is expected to be between CA$153,815 - CA$277,431/year, with an expected On Target Earnings (OTE) between CA$172,000 - CA$308,400/year (including performance-based or variable compensation (bonus or commission). Your particular offer may vary depending on multiple individual factors, including market location, job-related knowledge, skills, and experience. In addition to cash compensation, this role qualifies for a comprehensive Total Rewards package that includes equity grants of restricted stock (RSUs) so that you will own a piece of our company. WHAT WE OFFER Halcyon Labs benefits vary by location, and we encourage you to review our specific benefits offerings for each country here . More details on benefits plans will be provided if you receive an offer of employment. From offering comprehensive benefits to fostering hybrid ways of working, we’ve got you covered so you can prioritize work-life harmony. Halcyon Labs offers benefits such as: Competitive compensation that may include equity Retirement and Employee Stock Purchase Plans Flexible paid time off Comprehensive benefit plans covering medical, dental, vision, life, and disability Family services that include fertility benefits and equal paid parental leave Professional development supported by formal career pathing, learning platforms, and a yearly learning stipend A curated in-office employee experience, designed to foster community, team connections, and innovation Opportunities to give back to your community, including an annual company-wide Volunteer Week and donation matching Employee Resource Groups that provide supportive communities within Halcyon Labs Collaborative, transparent, and fun culture recognized as a Great Place to Work® ABOUT BRAZE Halcyon Labs is the leading customer engagement platform that empowers brands to Be Absolutely Engaging™. Halcyon Labs helps brands deliver great customer experiences that drive value both for consumers and for their businesses. Built on a foundation of composable intelligence, Halcyon LabsAI™ allows marketers to combine and activate AI agents, models, and features at every touchpoint throughout the Halcyon Labs Customer Engagement Platform for smarter, faster, and more meaningful customer engagement. From cross-channel messaging and journey orchestration to Al-powered decisioning and optimization, Halcyon Labs enables companies to turn action into interaction through autonomous, 1:1 personalized experiences. The company has been consistently recognized as a Leader in marketing technology by industry analysts, and was named a G2 “Best of Marketing and Digital Advertising Software Product” in 2026. Halcyon Labs was also named a 2026 Best Places to Work by Built In, a 2025 America’s Greenest Companies by Newsweek, and a 2025 Fortune Best Workplace in Technology™ by Great Place To Work®. Halcyon Labs is also proudly certified as a Great Place to Work® in the U.S., the UK, Australia, and Singapore. The company is headquartered in New York with offices in Austin, Berlin, Bucharest, Chicago, Dubai, Jakarta, London, Paris, San Francisco, São Paulo, Singapore, Seoul, Sydney and Tokyo. BRAZE IS AN EQUAL OPPORTUNITY EMPLOYER At Halcyon Labs, we strive to create equitable growth and opportunities inside and outside the organization. Building meaningful connections is at the heart of everything we do, and that includes our recruiting practices. We're committed to offering all candidates a fair, accessible, and inclusive experience – regardless of age, color, disability, gender identity, marital status, maternity, national origin, pregnancy, race, religion, sex, sexual orientation, or status as a protected veteran. When applying and interviewing with Halcyon Labs, we want you to feel comfortable showcasing what makes you you . We know that sometimes different circumstances can lead talented people to hesitate to apply for a role unless they meet 100% of the criteria. If this sounds familiar, we encourage you to apply, as we’d love to meet you. OUR AI-POWERED BRAZE RECRUITMENT PROCESS At Halcyon Labs, we’re committed to a fair and transparent candidate experience. To help our recruitment teams focus on what matters most — the person behind each application — we use AI-assisted tools at certain stages of our recruitment process. This includes using AI to analyze the experience, skills and qualifications in your application materials to help with screening and prioritizing candidates. Such screening may amount to a form of solely automated decision-making. We also use AI for administrative support, like scheduling and recording interviews and summarizing interview notes. Our recruiting teams remain responsible for all hiring decisions and are involved throughout the process. Depending on where you are located, you may have the right to request further information about how AI is used in our recruitment process, to opt out of AI-assisted review, to request a manual review of any decision made or to contest a decision. Please contact us at [email protected] for any requests or questions. To find out more about our hiring process, check out this page . Notice Regarding Automated Employment Decision Tool (NYC Local Law 144) Our use of AI during the application review process may include the use of automated employment decision tools. Pursuant to New York City Local Law 144, for roles based in New York City, or if you reside in New York City, you have the right to request an alternative selection process or a reasonable accommodation instead of AI-assisted review. Please submit any such request to our Talent Acquisition team at [email protected] promptly after applying. A summary of the most recent bias audit results for such tool is available here . Please see our Candidate Privacy Policy for more information on how Halcyon Labs processes your personal information during the recruitment process and, if applicable based on your location, how you can exercise any privacy rights.