Principal Solutions Architect – Core & Signaling

Skylo; Mountain View (CA); Hybrid; USD 180,000 - 200,000; Full time

Benefits offered by this job

Equity program

Comprehensive benefits

Wellness allowance

Time off and holidays

Satellite network project

Job summary

Skylo is seeking a Principal-level Technical SME to own the end-to-end technical integrity of our Core and Signaling architecture, bridging Satellite NTN and terrestrial networks. This role is hands-on, not a PM, and you will lead deep-room sessions with MNOs and define definitive technical repositories.

You will own end-to-end call flows for NB-IoT over NTN, drive 3GPP interfaces, document ICDs and HLDs, and mentor engineers while ensuring NTN constraints like high delay and Doppler are

Qualifications

• Extensive experience in 4G/5G Core Networks and signaling architectures.
• Proven ability to debug signaling at the packet level.
• Experience with NB-IoT over NTN and satellite-terrestrial integration.
• Strong documentation and diagramming skills.

Responsibilities

• Technical Authority: design and validate end-to-end call flows (Attach, PDN, Handover).
• Lead protocol discussions for S1, NAS, S6a (Diameter).
• Bridge UE to eNB/gNB considering NTN constraints (delay, Doppler).
• Lead workshops with MNO Core networks and drive system integration (S8, T7).
• Create and maintain ICDs, HLDs, and detailed call-flow diagrams.

Skills

Telecom network expertise

Technical leadership

Problem solving

Documentation skills

Cross-functional collaboration

Education

Bachelor’s degree in a related field

Tools

Wireshark

QXDM

Job description

About Skylo

Skylo is helping redefine how the world stays connected. At Skylo, our mission is to extend reliable connectivity to people, vehicles, and devices wherever they operate, even in the most remote and hard-to-reach places.

Skylo is a global connectivity company serving customers and partners worldwide. We enable satellite-based connectivity for everyday devices, helping smartphones, vehicles, and machines stay connected beyond traditional cellular coverage. Today, Skylo’s services are live on millions of devices across five continents, supporting use cases across consumer devices, automotive, and industrial sectors.

This role is located in North Americafollowing a hybrid working arrangement, spending 1–3 days per week based on the role and team needs.

Summary Of How You Will Impact Skylo

Skylo is looking for a Principal-level Technical Subject Matter Expert (SME) to own the end-to-end technical integrity of our Core and Signaling architecture. This is not a project management role; it is a “boots-on-the-ground” technical leadership position. You will be the ultimate authority on 3GPP 4G/5G signaling, responsible for designing the complex call flows that bridge Satellite (NTN) and Terrestrial networks. You will lead the “deep-room” technical sessions with MNO architects and build the definitive technical repository for Skylo’s core capabilities

What the role will look like – Core Responsibilities

1. Technical Authority & Protocol Design

• Signaling Master: Own the design and validation of end-to-end call flows (Attach, PDN Connectivity, Handover, SMSC timers, SMS over NAS) specifically for NB-IoT over NTN.

• 3GPP Interface Mastery: Act as the lead for all protocol-level discussions involving S1, NAS, S6a (Diameter).

• Air Interface Bridge: Deep-dive into the interaction between the UE and the eNB/gNB, ensuring the Core Network correctly handles NTN-specific constraints like high propagation delay and Doppler shifts.

1. Customer Technical Leadership (Deep-Dive)

• The “Black Belt” Interfacer: Lead high-stakes technical workshops with MNO (Mobile Network Operator) Core Network teams. You are the person they call when the conversation moves from “What does it do?" to “Show me the packet trace."
• System Integration: Design the complex roaming and interconnect architectures (S8, T7 interfaces) required to integrate Skylo’s NTN Core with global MNO partners.

1. Knowledge Engineering & Repository Lead

• Technical “Source of Truth”: Build and maintain the Skylo Technical Repository. This includes authoring:

• Interface Control Documents (ICDs) and High-Level Designs (HLDs).

• Detailed Call Flow Sequence Diagrams for every supported service.

• Troubleshooting guides for signaling “corner cases” unique to satellite environments.

• Understanding of GSMA Member gateway and should be comfortable with creating of IR.21 and updating the documentation and be part of technical working group at GSMA to represent Skylo

• Internal Training: Distill complex 3GPP and NTN concepts into training modules for the broader engineering and field teams.

1. CDR & Data Integrity (Liaison)

• Billing Alignment: Partner with the Settlement Lead to ensure that the Charging Trigger Functions (CTF) in the 4G/5G Core are generating accurate data for CDR creation.

What We Look For

• 12 Years of Telecom Rigor: Extensive experience in 4G/5G Core Network architecture (EPC and 5GC). You should have spent years “in the logs” (Wireshark, QXDM) at a major vendor (Ericsson, Nokia, Huawei) or a Tier-1 MNO.
• Protocol Forensics: Ability to debug complex signaling issues at the packet level. You should be able to identify a missing Information Element (IE) in a NAS message that is causing a registration failure.
• NTN Awareness: While SatCom experience is a plus, you must have the technical curiosity and foundational physics knowledge to understand how Long RTT (Round Trip Time) affects standard 3GPP timers (e.g., T3410, T3412).
• Documentation Specialist: A passion for clarity. You take pride in creating diagrams and documents that are technically flawless and easy to navigate

What We Offer

With employees working across three continents, Skylo is proud to be an equal opportunity employer dedicated to building an inclusive and diverse workforce. Our worldwide and inclusive culture encourages a flexible approach to work, and we also offer an attractive range benefits such as:

• Competitive compensation packages including a stock option based equity program
• Comprehensive benefits plans
• Monthly allowances for wellness and education reimbursement
• A generous time off policy and holidays
• Once in a lifetime opportunity to be a part of developing and running world’s first commercial, live direct-to-device satellite network and service
• Access to world-class team and talent across tech domains: software, hardware, chipsets, telecom, satellite and network virtualization

Why Join Skylo?

Skylo is helping redefine how the world stays connected. By bringing satellite connectivity into everyday devices, we’re breaking through long-standing limits of traditional networks and enabling new possibilities for safety, productivity, and access worldwide.

We’re not just building connectivity — we’re creating the foundation for a more connected world, where communication works wherever life and work take place. The challenges we solve are complex, real-world, and high-impact, and our work is already making a difference at global scale.

At Skylo, your work won’t stay on a whiteboard. You’ll contribute to live services used around the world, collaborate with talented teams across functions, and grow your skills while tackling problems that truly matter. If you’re excited by meaningful challenges, continuous learning, and building something that extends far beyond borders, Skylo is the place to do it.

Additional information

The compensation range for this position is: $180,000 – $200,000 plus equity. This range reflects the low and high end of the range Skylo reasonably and generally expects to pay the hired candidate in this role.

EEO Statement

Here at Skylo we are passionate and committed to our people. Our aim is to build a diverse and inclusive moment: teams of forward-thinking people, with unique talents, skills, passion and experience.

Its talent that matters to us and we encourage everyone to join us, whatever your gender identity, race, ethnicity, sexual orientation, age, life, experience or background. So, please come as you are – we cannot wait to meet you. We’d be thrilled if you tick off all our boxes yet we also believe it’s just as important we tick off all of yours. And if you think you have most of what we’re looking