BACKEND / Python Software Engineer (Senior)

Sadient; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Benefits offered by this job

Day 1 impact on product

Shape technical vision

Ground-floor opportunity

Job summary

Sadient in San Francisco is seeking a Senior Backend Engineer to lead core product development. Our backend powers REST APIs for iOS, Android, and Web frontends, using Python (FastAPI) with Postgres and Redis on AWS.

You will integrate with cryptocurrency wallet and banking providers, tackle real-money scale, and help shape architecture. The role offers Day 1 impact and potential leadership as the team scales.

Qualifications

• 5+ years building and shipping web apps in Python, Go, or Rust.
• Experience with Postgres, Redis, AWS in backend systems.
• Experience in financial technology.
• Full-stack capability to flex across the stack.

Responsibilities

• Lead core backend product development and API design.
• Integrate with wallet and banking service providers.
• Build a highly performant, secure, scalable backend.
• Evolve into a backend or engineering lead as we scale.

Skills

Python

Redis

Go

AWS

Rust

FastAPI

Job description

BACKEND / Python Software Engineer (Senior)

San Francisco, United States | Posted on 08/10/2026

Experience Required

5 years

Employment Type

Full Time

Skills

• Python
• Redis
• Go (Golang)
• AWS
• Rust
• FastAPI

We are hiring for a client in the social banking and digital wallet industry, driving innovation in consumer finance across emerging markets. The product focuses on building a joint virtual banking and cryptocurrency wallet platform, enabling users around the world to move seamlessly within a unified financial ecosystem with secure transactions, accessibility, and meaningful financial inclusion.

Our client is a well-funded, senior-only team based in San Francisco, led by founders with successful exits and supported by large global distribution partners. These roles offer high cash compensation and the chance to make an immediate Day 1 impact on a rapidly scaling product shaping the future of global consumer finance.

Job Description

We're seeking a Senior Backend Engineer to lead our core product development. Our backend serves a REST API that powers our iOS, Android, and Web frontends. You will integrate with cryptocurrency wallet and banking service providers, among other services for auth, ledger, payment rails, etc.

This is a financial services application with significant complexity handling real money at scale, internationally.

Our backend is a Python (FastAPI) monolith supported by Postgres and Redis on AWS. We are open to Rust and/or Go for any services that need to be broken out for performance.

This is a critically important role on our team. You'll be working directly with the technical founders to set standards and build a highly performant, reliable, and secure app from the ground up. This role may evolve into a backend or general engineering lead as we scale.

Requirements

• 5+ years building and shipping web applications in Python, Go, or Rust
• Experience generally across the backend: working with Postgres, Redis, AWS, etc.
• Experience in financial technology
• Full-stack engineering skillset and ability to flex across other parts of the stack

What We Offer

• Day 1 impact on partner products used by millions globally
• Shape technical vision and architecture as we scale
• Ground-floor opportunity in the rapidly expanding stablecoin ecosystem