Python Engineer, Financial Data Platform & Integrations

Cardiff

27d•Remote

About The Position

Cardiff is seeking a Python Engineer to join their Financial Data Platform & Integrations team. This role is crucial for building and maintaining the integrations and services that handle credit and bank transaction data, which are essential for Cardiff's underwriting decisions. The goal is to accelerate funding turnaround times by ensuring data is fast, reliable, and compliant, and to support the expansion of ML-based decisioning and LLM-based workflows. The position starts as an ongoing contract with a clear path to full-time employment, offering significant ownership and the opportunity to work with AI platforms from day one.

Requirements

5+ years of Python backend engineering experience on data-intensive systems, with recent, demonstrable work.
Experience building and operating production backend services in a modern Python framework (FastAPI preferred; Flask or Django acceptable), including API design, authentication, testing, and async programming.
Proven experience with reliable third-party API integration (retries, idempotency, rate limits, partial failures, observability), ideally with financial APIs from credit bureaus, banks, or payment processors.
Substantial hands-on Snowflake experience in production, including loading, modeling, and large-scale querying.
Experience with AWS data services for pipeline orchestration (Glue, Athena, S3, Step Functions, Lambda), including data lake layouts and partitioning for cost-efficient querying.
Strong data modeling, schema alignment, and transformation skills.
Working knowledge of API authentication, encryption, and compliance requirements for regulated financial data.
Proficiency in SQL and Pandas.

Nice To Haves

Experience with credit decisioning, loan underwriting, or financial risk data.
Experience with LLM APIs (Claude, OpenAI, or equivalent) for extraction, classification, or summarization, including prompt design, evaluations, output validation, RAG, and embeddings.
Experience using AI-assisted development tools (Claude Code, Cursor, Codex, Devin) as a primary mode of building.
Experience with CI/CD pipelines.

Responsibilities

Design, build, and run FastAPI services that expose financial and credit data to internal consumers, including API design, authentication, versioning, pagination, and error handling.
Own the integration layer with external providers such as Experian, Plaid, and bank transaction sources, managing retries, backoff, rate limiting, credential handling, and graceful degradation.
Build pipelines to land provider data in Cardiff's systems, including Snowflake, using serverless ETL on AWS (Glue, Athena, Step Functions, S3 data lakes), supporting both batch and near-real-time ingestion.
Perform data modeling and schema mapping to ensure semantic consistency of disparate provider formats, collaborating with domain experts and analysts.
Build integrations that comply with Cardiff's security, privacy, and regulatory obligations, working with Legal, Compliance, and Security teams.
Apply LLM APIs for extraction and classification of unstructured documents, ensuring model outputs are validated before entering the pipeline.
Utilize AI tooling as part of the development process, reviewing and validating AI-generated output.
Maintain unit tests, integration tests, and documentation for all owned components.