Senior Software Engineer

Experteer Overview As a Sr. Software Engineer at Billtrust, you will design and deliver complex features across our SaaS platforms, leveraging AI tools to accelerate development and ensure high quality. You’ll work within a domain-aligned cohort to influence architecture, mentor peers, and ship scalable solutions. Your work helps advance our AI-assisted development practices and supports a fast-growing fintech product. This role offers meaningful impact at the frontier of AI and fintech. Compensation / Benefits * Own end-to-end feature specification ensuring completeness and edge-case coverage * Collaborate with Product Manager to translate requirements into technical specs * Lead technical decisions and contribute domain expertise within the cohort * Drive AI-assisted implementation and review AI-generated code for correctness, security, and performance * Validate AI-generated tests and ensure broad test coverage for complex scenarios * Improve AI-assisted development practices (spec templates, prompt patterns, validation workflows) * Design scalable software with a DevOps mindset and implement REST APIs * Maintain both UI and backend services within the cohort domain * Mentor engineers on AI tool usage, spec writing, and code review; share knowledge across cohorts * Support and collaborate with cross-functional teams across the organization Tasks * 5+ years of relevant software engineering experience with scalable SaaS * Bachelor’s degree in Computer Science or equivalent * Proficiency in C#, C++, PHP, Java, Node.js or similar * Strong web tech skills: HTML5, CSS/Sass, Angular, React, TypeScript/JavaScript, REST APIs * Strong SQL and relational DB knowledge (SQL Server or MySQL) * Experience with AI coding assistants (Claude Code, Codex, Cursor) and code review skills * Collaborative and communicative, with mentoring experience * GIT or similar source control experience Key requirements * comprehensive health coverage * competitive retirement plan * generous PTO and parental leave * flexible work options * professional development investments * equity or variable incentives may apply

our templates, prompt patterns, validation workflows) * Design scalable software with a DevOps mindset and implement REST APIs * Maintain both UI and backend services within the cohort domain * Mentor engineers on AI tool usage, spec writing, and code review; share knowledge across cohorts * Support and collaborate with cross-functional teams across the organization Tasks * 5+ years of relevant software engineering experience with scalable SaaS * Bachelor’s degree in Computer Science or equivalent * Proficiency in C#, C++, PHP, Java, Node.js or similar * Strong web tech skills: HTML5, CSS/Sass, Angular, React, TypeScript/JavaScript, REST APIs * Strong SQL and relational DB knowledge (SQL Server or MySQL) * Experience with AI coding assistants (Claude Code, Codex, Cursor) and code review skills * Collaborative and communicative, with mentoring experience * GIT or similar source control experience Key requirements * comprehensive health coverage * competitive retirement plan * generous PTO and parental leave * flexible work options * professional development investments * equity or variable incentives may apply