Project Overview & Role Summary
I am seeking an experienced Senior Python Developer to take technical ownership of a core financial calculation engine for a debt modeling calculation engine.You will begin with an existing, functional Python codebase that models a wide array of complex debt structures, as well as a JSON file from which the calculation engine will get its parameters. This engine serves as the foundation of our product.Your primary objective is to partner with the founding domain expert to enhance, scale, and productionize this engine. This involves implementing new financial features based on detailed specifications, building a comprehensive automated testing suite from the ground up, and deploying the engine as a robust REST API.
Key Responsibilities
Own and Enhance the Calculation Engine: Take ownership of the existing Python calculation engine. Understand its architecture, refactor where necessary, and implement new financial features based on clear specifications provided by the domain expert.
Build a Comprehensive Testing Suite: Build out a robust, automated testing suite using a framework like pytest. This will involve writing unit tests for individual financial calculations and integration tests for end-to-end scenarios to guarantee accuracy and prevent regressions.
Develop and Deploy a REST API: Design, build, and deploy a clean, efficient REST API (e.g., using FastAPI) that serves as the public interface to the calculation engine. This API will accept a structured JSON payload (conforming to our defined schema), pass it to the engine for processing, and return the resulting cash flow data.
Collaborate on System Architecture & Schema Design: Work in a close-knit partnership with the founder. Your role will be to take high-level financial concepts and business rules and translate them into a robust, evolving JSON schema. You will then enhance the calculation engine to match the schema you helped design, providing technical feedback and architectural solutions along the way.
Ensure Code Quality and Reliability: Write clean, maintainable, and well-documented code. Implement robust error handling and logging to ensure the engine is production-ready.
Technical Requirements & Qualifications
Expert-Level Python: 5+ years of professional experience with a deep understanding of modern Python (3.8+), including dataclasses, enums, and object-oriented design principles.
API Development: Proven experience building, deploying, and maintaining RESTful APIs. Experience with frameworks like FastAPI or Flask is highly desirable.
Financial Data Handling: Experience working with Python's decimal library for high-precision financial calculations.
Automated Testing: A strong belief in the value of testing. Deep experience with testing frameworks like pytest, including writing both unit and integration tests.
Experience with financial libraries such as numpy-financial.A general familiarity with financial concepts (e.g., amortization, interest rates, present value). Experience integrating with third-party APIs, particularly LLM APIs (e.g., OpenAI).Familiarity with data validation libraries like Pydantic.