Software Engineer (Early Career) at Phonely (S24)
$60K - $80K  •  
AI call centers
San Francisco, CA, US
Full-time
US citizen/visa only
Any (new grads ok)
About Phonely

About Phonely

There are billions of calls made every day which will soon be handled by AI. Today 70% of business customer support calls are outsourced to call centers and contact centers. These call centers are looking for a solution that they can build simulate, and deploy voice agents all in one platform. We are building this.

Through YC we grew at 22% week over week and went through demo day with the some of the top revenue in the batch. We already work with the largest contact centers in the world and are looking for people that want to build the future of AI phone support together.

About the role

About Phonely

Every day, billions of phone calls are made to businesses. AI will soon power the majority of them. Businesses need a way to build, simulate, integrate, and deploy voice AI agents—we are building this.

To create AI voice agents that can truly match human performance, we need 99.999% reliability. We’ve achieved this by building fine-tuned LLMs, real-time monitoring, Zapier-like automation, and robust infrastructure that can scale instantly.

We are scaling quickly—our company grew 22% week over week in YC, finishing in the top 5% of companies by revenue in our batch, closed a seed round, and haven’t stopped growing. We are now looking for a Forward Deployed Engineer to join us in San Francisco (or willing to relocate) and help our customers scale to millions of calls.


What You Will Do

  • Diagnose and debug issues across systems, including state inconsistencies, API failures, and AI behavior anomalies
  • Collaborate with senior engineers to execute QA workflows, design adversarial test cases, and stress-test our Voice AI models for robustness and reliability.
  • Use telemetry and metrics tools like Datadog to investigate production issues and support customer-facing incidents.
  • Work directly with customers to understand technical needs and build integrations.
  • Solve critical technical issues in real-time, troubleshooting infrastructure and API failures.

Competencies

Strong programming ability with experience in backend engineering, API integrations, or full-stack development.

Problem solver with a consultant mindset—able to diagnose issues and build solutions quickly.

• Clear communicator who can explain complex technical topics simply.

• High execution mentality—moves fast and takes ownership of outcomes.

• Ability to withstand long hours and eating whatever Yonge makes for dinner.


Why Join Us?

“I worked for IBM for the past 10 years. I started working for Phonely 3 months ago and I could never imagine going back. The growth of this company since I joined has been insane—I feel like I’m living in a movie.”

— Aidan Hallett, Founding Engineer

At Phonely, you’ll be working on the future of AI voice technology, solving problems that no humans have ever solved before, and changing the way people answer the phone forever.


Tech Stack

• Core Technologies: Python, Next.js, TypeScript

• AI Tools: OpenAI, Llama 3, Anthropic, Speech-to-Text, Text-to-Speech

• Infrastructure: AWS, Kubernetes, Datadog

Who Should Apply

  • You're a student or recent grad with a strong technical foundation and a passion for building real-world products.
  • You thrive in fast-paced, startup environments and are excited to learn by doing.
  • You take initiative, ask questions, and aren’t afraid to roll up your sleeves and figure things out.
  • You're curious about AI and eager to work on cutting-edge voice technologies.
  • You're excited by the idea of shaping the future of real-time, AI-powered voice interactions.
  • You’re down to work hard, move fast, and maybe stay up late solving interesting problems.

You want to learn from and collaborate with some of the most driven (and fun) people you’ve ever met.

Day to Day

At Phonely, no two days are the same. As a Software Engineer / Forward Deployed Engineer, you’ll be hands-on with real customers, real AI, and real impact from day one.

  • Dive into real customer calls, pull out insights, and help make our AI smarter
  • Build custom workflows and automations that power millions of calls
  • Dig through logs, debug weird edge cases, and solve problems that actually matter
  • Stress-test new features before they hit production
  • Work directly with clients—present findings, fix issues, and help them scale fast
  • Collaborate with the engineering team to ship improvements quickly

You’ll get a front-row seat to how voice AI is built and deployed at scale—and as we grow, this role naturally evolves into a full software engineering position. If you’re excited by fast feedback loops, real-world impact, and working with a sharp, driven team, you’ll thrive here.

It’s hard work, but you’ll learn a ton, move fast, and have fun doing it.

About the interview process


Step 1: 15 minute interview

  • A quick call to discuss your experience, skills, and interest in Phonely.

Step 2: Team Interview

  • Meet with key team members, learn about our culture, and discuss your potential role.

Step 3: Technical Project

  • A short real-world coding project relevant to your role.

Step 4: One-Week Live Co-Working Session

  • Join us on-site in San Francisco for a one-week trial period, working on real projects.
Technology

To achieve human-level performance with voice AI agents, we need 99.9% reliability across all verticals. Building a high-performing Voice AI solution requires a combination of key elements:

  1. Voice AI Infrastructure: Develop robust systems that can handle real-time conversations seamlessly.
  2. API Integrations: Connect with relevant software to ensure smooth interactions.
  3. LLM Testing, Simulation, and Evaluation: Validate models under various conditions to ensure accuracy.
  4. Performance Monitoring: Continuously track metrics to optimize system performance.
  5. Countless Other Tasks: From scaling infrastructure to managing edge cases, achieving this level of reliability is no small feat.

We’ve brought all of these elements together in one place so enterprises can integrate reliable and accurate voice AI into their offerings in minutes, not months.

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