Top Senior Software Engineer Jobs in Sacramento, CA

Design, build, and maintain scalable, reliable full‑stack systems. Contribute to API and architecture design, write testable code, debug complex issues, improve performance, automate deployments, and mentor junior engineers while collaborating with cross‑functional teams.

Lead design and development of Java/Spring and React applications for genomic variant identification and clinical reporting. Architect data models, APIs, and search strategies for large-scale variant data. Partner with scientific and clinical experts, drive technical direction, mentor engineers, troubleshoot production issues, and improve reliability, observability, and performance.

As a Billing & Analytics Software Engineer, you'll design and maintain the billing pipeline, integrate billing systems, and develop customer-facing analytics dashboards to support revenue recognition and operational observability.

Lead full‑stack design and delivery of customer-facing web experiences (Browse, Navigate, Preview). Own architecture, APIs, data models, rollouts, observability, on‑call readiness, and cross-team alignment, using approved AI-assisted workflows while ensuring technical quality and reliability.

Lead design and delivery of scalable customer-facing features, services, and APIs that process real-time data and AI-powered insights. Build web experiences, contribute to LLM/AI workflows, ensure reliability through observability and rollout practices, and collaborate cross-functionally with Product, Design, ML, and platform teams.

Lead development and maintenance of high-performance React Native apps across iOS and Android. Improve architecture, manage RN upgrades, debug native modules, own automated testing and CI/CD, optimize performance and stability, and mentor engineers within cross-functional product pods.

The role involves leading application performance improvements across multiple platforms, focusing on measurable metrics and driving engineering standards and workflow optimization, using both hands-on coding and strategic influence.

The Software Engineer will enhance Lending products for Cash App, focusing on building complex systems, APIs, and collaborating with multiple teams to support economic empowerment through accessible credit.

Lead UI architecture and design for responsive web applications; build reusable components with Angular/React/Vue and TypeScript/JavaScript; integrate UIs with RESTful microservices; enforce accessibility, security, testing, and CI/CD standards; mentor developers and collaborate with UX, backend, and DevOps teams in Agile environments.

Design and implement CIAM backend services for authentication and authorization. Integrate identity systems, manage secure flows, and automate infrastructure.

The Senior iOS Engineer will lead key engineering decisions, ship production code for the Speechify iOS app, and maintain complex app architecture while contributing to product discussions.

As a Senior Principal Engineer, you'll define and drive the technical strategy for customer experience platforms, lead architectural decisions, and mentor engineering teams to enhance customer and agent experiences.

Lead design and operation of Block's real-time, event-driven data systems. Build and run high-throughput streaming pipelines, turn Kafka event streams into low-latency data products, improve reliability and observability, mentor engineers, and define platform architecture and standards for projections, third-party data proxy, and graph data capabilities.

Build and maintain on-chain smart contracts and backend services for branded USDC-backed stablecoins. Own issuance, reserves, mint/burn, and rewards systems; drive architecture, security, and operational excellence; ship features with product and design partners and ensure well-tested, auditable production deployments.

Design, scope, and implement scalable backend and platform solutions for a reservations and waitlist product. Improve performance and usability, collaborate with Product and Design, identify high-impact opportunities, and contribute across the stack including APIs and front-end integration.

Lead technical strategy and architecture for Affirm Bank's cloud, data, vendor integrations, and operational tooling. Design, build, and operate high-stakes systems end-to-end, own incident response, vendor selection, and the Bank↔Affirm Inc integration boundary. Ensure examiner-ready documentation, compliance, reliability, and observability while mentoring engineers and pushing AI-assisted engineering practices to increase velocity and product safety.

Lead architecture, modernization, and development of Group Insurance applications. Modernize mainframe monoliths into Java microservices and micro-frontends on cloud, mentor distributed Agile teams, collaborate with enterprise architecture, product owners and infrastructure, and enable test automation and integrations. Approximately 10% domestic travel.

Design, build, and operate scalable, secure data platform infrastructure for ingesting, processing, cataloging, and accessing petabytes of data. Improve Spark/Databricks reliability and developer experience, build ingestion/replication systems, develop internal libraries and tooling (Go/Python), and collaborate with cross-functional teams to support analytics, ML, and customer-facing data products.

Lead design and build of scalable AWS cloud-based backend services and APIs powering web and mobile customer experiences. Own end-to-end feature delivery, improve grading and authentication workflows for scale and reliability, leverage AI tools to accelerate development, and provide technical leadership and mentorship across teams.

As a Senior Software Engineer, you'll design, develop, and maintain full-stack applications, utilizing TypeScript and modern frameworks while collaborating cross-functionally to enhance user experience and performance.

Design, build, and operate distributed ledger, transaction, settlement, and treasury systems. Develop durable ledgering APIs, emit trusted data for finance, maintain high-reliability services to SLOs, lead complex cross-team projects, mentor engineers, and integrate AI tooling across the development lifecycle.

The Software Engineer will design, develop, and maintain software solutions using C#, .NET, and React in diverse environments, ensuring compliance and optimal performance.

Looking for a Software Engineer to build financial products and tooling for Cash App's Lending team, ensuring quality and compliance while collaborating across domains.

Lead design and delivery of a reliability platform for production systems. Own quarterly goals, guide engineers through ambiguity, collaborate with PM/design/analytics, monitor and operate services (on-call), set quality and code standards, and mentor teammates. Integrate AI/LLM tooling to improve automation, debugging, and service health.

Lead delivery for the Batch Infrastructure team: design, build, and operate reliable, scalable compute platforms for scheduled and on-demand batch workloads. Collaborate with product/design/analytics, define technical plans, ensure availability (monitoring/on-call), set code and design standards, and mentor engineers to improve delivery and quality.