Principal Sales Engineer - Solutions & Partner Enablement - Network APIs

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Location:

Bellevue, WA (Hybrid) – Onsite at least 3 days/week. This role is not remote.

T-Mobile's Network as a Service (NaaS) team builds innovative network API products that empower developers, partners, and enterprises to build their differentiated digital solutions. Our mission is to solve enterprise challenges with scalable, developer‑friendly solutions that tap into T‑Mobile's differentiated network capabilities.

As a Principal Sales Engineer, you'll be the technical leader driving developer and partner adoption and enablement for our NaaS platforms and APIs. You'll guide customers from first conversation through production‑shaping world‑class developer experiences, accelerating integrations, and ensuring successful deployments. You'll partner closely with Business Development and Product to turn network APIs into real business outcomes.

• Act as the bridge between Product and Business Development, ensuring customer needs align with product capabilities.
• Support presales conversations by understanding customer requirements and showing how our products deliver value.
• Educate customers on how to use our products effectively through demos, technical discussions, and proof‑of‑concepts.
• Serve as the main technical and product point of contact after the deal is signed, driving smooth onboarding and integration.
• Partner with product managers to create key materials such as presales decks, solution architectures, and technical documentation to support customer and partner engagement.
• Gather customer feedback to influence product roadmap and improve the overall experience.

• Deep expertise in APIs, SDKs, and developer platforms, with strong engineering fundamentals and integration skills.
• Sharp business context understanding to assess customer needs and align technical solutions with business goals.
• Strong product sense to translate complex capabilities into clear customer value.
• Hands‑on experience leading presales and post‑sales technical engagements for enterprise customers.
• Proven ability to manage complex projects and drive execution across product, engineering, and GTM teams.
• Excellent communicator who can bridge technical depth with business clarity and executive impact.
• Adaptive, agile, and growth‑oriented mindset—comfortable operating in ambiguity, shifting priorities, and driving continuous learning and improvement.

• Bachelor's degree in Engineering, Computer Science, or a related field (required).

• 10+ years in Sales Engineering, Solutions Engineering, or Product Management across APIs, developer platforms, or enterprise SaaS.
• Proven track record driving presales and post‑sales success through deep technical engagement and business alignment.
• Strong experience leading customer onboarding, partner integrations, and solution delivery at scale.
• Deep understanding of API management, SDK development, and cloud infrastructure.
• Hands‑on experience managing complex technical programs using Agile methods and iterative delivery.
• Exposure to AI‑ or automation‑driven developer tools and modern API lifecycle management (preferred).
• Demonstrated ability to influence product strategy and collaborate effectively with senior business and engineering leaders.

You’ll be the connector that turns T‑Mobile’s network capabilities into real customer and partner impact. This role blends product, engineering, and business—helping shape how customers understand, adopt, and succeed with our network APIs. You’ll operate like a startup inside a large enterprise: moving fast, solving ambiguous problems, and driving both strategy and execution. If you thrive at the intersection of technology,…