Senior Full Stack Engineer

PetsApp; Boston (MA); On-site; USD 170,000 - 180,000; Full time

Job summary

PetsApp is seeking a skilled Back End Engineer to join their team in Boston. This role focuses on optimizing the lending system, developing RESTful APIs, and leading technical architecture decisions. The position requires strong Python and Django skills, as well as experience with database optimization.

The expected salary range is between $170,000 and $180,000 based on qualifications. Applicants with any type of work authorization are welcome to apply.

Qualifications

• 5+ years of professional Python development experience.
• Strong expertise in the Django framework.
• Advanced knowledge of SQL and database optimization techniques.
• Proven experience in REST API design and development.
• Demonstrated ability to lead technical projects and mentor junior engineers.

Responsibilities

• Optimize and resolve performance bottlenecks in lending systems.
• Develop and maintain robust RESTful APIs.
• Refactor deal calculation library for efficiency.
• Optimize database queries and schema design.
• Lead and collaborate on architectural solutions.

Skills

Python development

Django

SQL

REST API design

Docker

AWS Infrastructure

Microservices architecture

Tools

Postgres

Airflow

React

Job description

About

Daylit is a leading AI agent platform for accounts receivable. Our platform automates the manual work of collecting and reconciling invoices so finance teams can scale credit and collections teams without adding headcount. Our customers trust Dayilt to deliver a complete view of portfolio health — surfacing at-risk accounts, predicting payment timing, and powering accurate cash flow forecasts. Companies with high invoice volume use Daylit to reduce DSO, eliminate repetitive work, and know exactly when cash will hit the bank.

The Role

We are seeking a highly skilled and motivated Back End Engineer to join our team and play a critical role in ensuring the stability, performance, and scalability of our core platform. This role will focus on optimizing our lending system, payment processing process, designing and implementing API improvements, and leading technical architecture decisions. The ideal candidate will have a strong background in Python and Django, a deep understanding of database optimization, and a proven track record of leading technical projects.

What You’ll Do

• Optimize and Scale Core Lending Systems: Identify and resolve performance bottlenecks, improve reliability, and ensure the security of our lending and payment processing infrastructure.
• Design and Implement API Routes: Develop and maintain robust and efficient RESTful APIs to support our growing product offerings.
• Refactor Deal Calculation Library: Improve the efficiency and maintainability of our deal calculation library, ensuring accurate and timely calculations.
• Improve Database Performance: Optimize database queries, schema design, and indexing to enhance overall system performance.
• Lead Technical Architecture Decisions: Collaborate with the team to define and implement scalable and maintainable architectural solutions.
• Contribute to code reviews, documentation, and participate in Agile development processes.

What You’ve Done

• 5+ years of professional Python development experience
• Strong expertise in the Django framework
• Advanced knowledge of SQL and database optimization techniques
• Proven experience in REST API design and development
• Demonstrated ability to lead technical projects and mentor junior engineers
• Experience with Docker and containerization technologies
• Experience in AWS Infrastructure, such as ECS, Lambda, RDS a plus
• Hands‑on experience with lending/payment processing systems a plus
• Experience with microservices architecture a plus
• Experience working with frontend team/React App CICD/testing framework a plus
• Familiarity with data science and engineering tools such as Pandas, scikit‑learn, Airflow, Hubspot, and Confluent a plus

Our Tech Stack

• Backend - Django, Airflow, Postgres
• Frontend - React
• Infrastructure - Docker, ECS, Airflow, Pulumi or Terraform, Github Action, Prometheus/Grafana
• CRM - Hubspot
• Others - Retool, Google Analytics

The expected salary range for this role is between $170,000 - $180,000, depending on qualifications and experience.

Note that this role is based in our Back Bay office in Boston. Daylit welcomes applicants with any type of work authorization.