Senior Backend Engineer (Series A Backed)
Phonely
Senior Backend Engineer (Python) This role is in office 5 days a week in San Francisco. About the role We are building voice AI for businesses and want an experienced engineer to help design, build, and maintain the systems that drive real‑time conversations. The role is highly dynamic, requiring deep technical expertise and a hands‑on approach. Day to Day Responsibilities Build and maintain Python–based state systems that drive what the voice AI says and does across complex, real‑time conversations. Integrate and orchestrate multiple LLM providers, including prompt design, tool/function calling, routing, and fallbacks. Write clean, maintainable, high‑performance Python code, leveraging asyncio, OOP, and best practices. Write automated tests and validation suites to ensure correctness, resilience, and safe iteration of agent logic and state transitions. Monitor production systems, debug agent behavior, and continuously improve reliability and conversation quality. Implement comprehensive metrics, logging, and alerting to validate correctness, detect failures early, and maintain extremely high availability. Design database schemas, optimize queries, and operate both SQL and NoSQL databases in production. Build and operate authentication and authorization mechanisms with strong security guarantees. Design and build microservices‑based architectures. Qualifications 5+ years of experience writing Python, including async web apps using FastAPI and testing frameworks. Strong understanding of LLMs, APIs, cloud, and CI/CD pipelines. Comfortable interpreting technical specifications and designing sound architecture. Knowledge of security best practices in backend development. Excellent communication skills with great teamwork and collaboration. Experience with AWS and Kubernetes, and managing scalable infrastructure. Our Software Stack Backend: Python, microservices, async programming. Cloud & Infrastructure: AWS, GCP, Kubernetes, Redis. Databases: Firebase, Supabase. Observability & Monitoring: Datadog, logging, metrics, tracing. Telephony & Voice AI: SIP, voice APIs, real‑time call handling. Front‑end: Next.js. Other tools & practices: CI/CD, automated testing, resilient architecture. #J-18808-Ljbffr Phonely
- ...functions About The Role An emerging venture-backed firm is reshaping how companies... ...legacy constraints. They raised a $20M Series A and recently secured a Series B. You’ll collaborate with a focused group of engineers driving the development of a platform that...SeniorWork at officeRelocationFlexible hours
$250k
Acceler8 Talent is seeking a Senior Software Engineer in San Francisco, CA, to develop AI-powered backend workflows and scalable infrastructure. The ideal candidate... ...opportunity to work on cutting-edge AI infrastructure backed by Series B funding, with a competitive salary package...Senior$250k
Senior Software Engineer (Python) - San Francisco, CA A fast‑growing deep‑tech startup is building... ...I Be Doing? Building AI‑powered backend workflows and distributed systems.... ...and intelligent automation tooling. Backed by strong Series B funding with significant growth...Senior- Job Title Senior Backend Engineer Hiring Location San Francisco, USA Company Description Casa is a $27M Series A startup building the operating system for homeownership, backed by Forerunner Ventures, Sandberg Bernthal Venture Partners, and Travis Kalanick. Job Description...SeniorRelocation
$200k - $260k
...-site in San Francisco, CA Are you a senior backend engineer who takes pride in building reliable,... ...Netflix, and NASA depend on in production. Backed by top-tier investors, the team has... ...company before they raise their Series A, this is an outstanding opportunity....Senior$249k - $405k
...process. We recently raised our Series B and have grown 800% over the last 12 months. Engineering at us Engineers with us are... ...problems (and more) at scale, and our Backend Engineers make it possible. You... ...give these lawyers their lives back, and at us, that’s our mission....SeniorContract workWork at officeRelocationVisa sponsorshipRelocation package$210k - $285k
...Description Job Description Senior Backend EngineerAbout the Role We're hiring a Senior Backend Engineer to own and scale the core... ...and operational workflows. Backed by leading venture capital firms... ...Experience at a high-growth Series A/B startup or as a founding...SeniorFull timeH1bRelocationVisa sponsorshipFirstchoicedrivers
San Francisco, CA26 days ago$195k - $280k
...cutting-edge thinking with the long-term backing of leading insurer, State Farm.... ...insurance technology innovation company that engineers advanced risk prediction and prevention... ...quantifiable impact. The role We're seeking a senior backend engineer to build and enhance the...SeniorRemote jobExtra incomeLocal areaWork from homeHome officeFlexible hoursQuanata
San Francisco, CA25 days ago- ...We are looking for a talented and driven backend engineer with system design and architecture experience. This position entails complete... ...You are an active Web3 user. You have worked with time-series data and specialized databases: ClickHouse, TimescaleDB, etc....SeniorWork at officeRemote workWork from homeWorldwideRelocationRelocation packageFlexible hours
GrabJobs
San Francisco, CA7 days ago $210k - $240k
Postman is seeking a high-ownership infrastructure engineer in San Francisco to enhance their backend infrastructure, focusing on time-series network traffic. The role requires 7+ years of experience and involves collaborating with teams to address technical challenges...SeniorFlexible hours- A venture-backed Health-Tech company in San Francisco is seeking a Senior Backend Software Engineer to design and maintain their product suite. You will play a key role in all stages of the software lifecycle, collaborating with teams and mentoring junior engineers. Candidates...Senior
- EvenUp in San Francisco is seeking experienced software engineers to build impactful technology aimed at improving justice for injury victims... ...candidates will have considerable experience in front-end or back-end development and a passion for tackling complex challenges...SeniorWork at office
$163.5k - $284k
Superhuman, located in San Francisco, is seeking a Back-End Engineer to join their innovative team. This role offers a hybrid working model, allowing for both focused work and in-person collaboration. You'll be responsible for building and operating high-throughput production...Senior$160k - $210k
Ellipsis Health is seeking a Senior Backend Engineer to design, build, and scale core systems for their conversational AI platform. Located in San... ...the US. The ideal candidate should have over 5 years of back-end development experience, particularly with TypeScript and...SeniorRemote job- ...enterprises like Roblox. Complete is backed by Accel and YC. We're also lucky to count... ...point and we7;re looking for a Senior/Staff Engineers to help scale us to a $XXM+ in ARR. You... ...but have the caliber to scale: Python backend (primarily Django) with Postgres Clerk...SeniorWork at officeFlexible hoursWeekend workAfternoon shift
Complete
San Francisco, CA1 day ago $500 per month
...Dogpatch neighborhood. About Giga Giga has recently raised a $61M Series A and is working with Fortune 500 customers to deploy the... ...defines generational companies. The Role We’re looking for backend engineers to build the infrastructure and systems that power our AI agents...SeniorGiga
San Francisco, CA7 hours ago- A health-tech company based in San Francisco is seeking a Senior Backend Software Engineer. This role focuses on back-end architecture, involving designing scalable APIs and databases, and collaborating with different teams. Candidates should have 5-8 years of software...SeniorFlexible hours
$200k - $250k
Senior Backend Engineer - build the infrastructure behind a product that changes people's lives Are you a backend engineer who thinks as much... ...using it They’re based across San Francisco and New York, backed by strong investors, and scaling their engineering team off...SeniorH1bVisa sponsorship- ...experiences, and build a legacy that inspires future generations. Senior Backend Engineer Primary: Bay Area (San Francisco / Peninsula) | Secondary:... ...you design for scale and reliability with the metrics to back it up. Pragmatic: You balance short-term delivery against...SeniorTemporary workWork at officeRelocation packageFlexible hours2 days per week
Mrbeastyoutube
San Francisco, CA7 hours ago - ...Clarke are partnered with a high-growth VC-backed AI company operating at the intersection... ...Design, build, and operate backend services that support a rapidly growing... ...background: Degree in Computer Science, Engineering, or a related field, plus 5+ years of backend...Senior
$180k
...underserved markets. Our client has big plans for 2017 and is rapidly building out their engineering team to accomplish them all. They are looking to add a number of Junior Back End Engineers to the team immediately. Job Description The Role As a Back End Engineer (junior...SeniorImmediate start- ...on this job and more exclusive features. We’re looking for a senior backend engineer who can architect and scale core systems, take full... ...interviewing at Stealth AI Startup by 2x Get notified about new Back End Developer jobs in San Francisco Bay Area . Alameda, CA $...SeniorFull time
$140k - $200k
Join to apply for the Senior Backend Engineer role at HumanSignal HumanSignal is building the platform that powers the creation, curation, and... ...with background processing/queues (e.g., Celery/RQ/Kafka‑backed workers) and operational concerns. Clear written communication...Senior- We are seeking a brilliant engineer to help accelerate the build out of our client-facing content marketing platform. The candidate will... ...Responsibilities Autonomously deliver key new features for our back-end systems Improve performance, scalability, maintainability,...SeniorRemote job
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...was recently named to Fortune’s Future 50 list for 2025 and is backed by world-class investors including General Catalyst, Sequoia,... ...real-time access to patient data. We're looking for talented Backend Engineers to help us build our health-tech products. If you love...SeniorFull time- ...generative creativity. We're well-capitalized and looking for a founding engineer to own the back end of Variant. The ideal candidate: Has impactful experience at a company known for its sophisticated backend, contributed to a notable open source project, or has an impressive...Senior
$210k - $240k
...for a high‑ownership, product‑oriented infrastructure engineer to help us scale our product to bigger users. Postman... ...needs. What you’ll do Design, build, and scale our backend infrastructure to process time‑series network traffic, at large scale, in real‑time. Build...SeniorTemporary workFlexible hours- ...Archiving Solutions, raised a $20 million Series B funding round—bringing our total... ...run on. We want builders, not just users: engineers who have stood up an agentic framework end... ...would do differently. 6+ years building backend systems or distributed infrastructure at...SeniorWorldwideFlexible hours
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$140k - $220k
...,000.00/yr - $220,000.00/yr About Our Engineering Team: At David AI, our engineers build... ...generative audio models. About This Role As a Senior Backend Engineer at David AI, you’ll work... ...growth at one of the fastest growing Series A companies, within a new and booming industry...SeniorFull timeWork at officeFlexible hours
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