Skip to main content

Embedded C Developer – OpenSync/ WiFi Gateway-OnSite

00070343081

Embedded C Developer – OpenSync/OpenWrt WiFi Router with Cellular Backup

About the Role

We're looking for an Embedded C Developer to work on next-generation residential gateway platforms that combine DOCSIS/fiber WAN connectivity with LTE/5G cellular backup. You'll be developing and maintaining firmware on OpenWrt-based hardware running the OpenSync framework, with direct impact on millions of deployed customer premises equipment (CPE).

Responsibilities

• Design, develop, and debug embedded C software for Linux-based residential gateway platforms (ARM/MIPS SoC)

• Develop and maintain OpenSync managers — event-driven daemons that interact with OVSDB for cloud-managed configuration and state reporting

• Implement and optimize LTE/5G cellular failover and fallback logic including modem management, route arbitration, and WAN healthchecks

• Develop LED state machine logic to provide accurate device status indication across complex multi-WAN scenarios

• Interface with cellular modems via AT commands, QMI/MBIM, USB, and PCIe (MHI) protocols

• Work with WiFi drivers (Qualcomm/Broadcom/Atheros) for 2.4GHz, 5GHz, and 6GHz radio configuration

• Debug kernel-level issues including PCIe enumeration, USB device management, network driver crashes, and kernel panics

• Implement and maintain secure communication channels using TLS with mutual authentication and tunneling protocols

• Analyze and resolve field issues using device logs, crash dumps, and remote diagnostics

• Develop init scripts, UCI configuration handlers, and persistent storage management for OpenWrt

• Write unit tests and participate in code reviews via GitLab merge requests

• Collaborate with hardware teams, QA, cloud platform engineers, and service provider partners

Required Skills

• 5+ years of embedded C development on Linux-based platforms

• Strong proficiency in C programming — pointers, memory management, IPC, event-driven architectures

• Experience with OpenWrt build system, package management, UCI configuration, and JFFS2/SquashFS overlay filesystems

• Familiarity with OpenSync or similar cloud-managed CPE frameworks (OVSDB, protobuf, MQTT telemetry)

• Experience with cellular modem integration — AT commands, QMI, network interface management (rmnet/wwan)

• Strong understanding of Linux networking — routing tables, metrics, netfilter, bridge interfaces, IPv4 and IPv6 dual-stack, neighbor discovery, DHCPv4/DHCPv6, SLAAC, and prefix delegation

• Understanding of TLS handshake with mutual authentication using X.509 certificates, certificate chain validation, and secure provisioning

• Knowledge of security and tunneling protocols — GRE tunneling, IPsec, VPN overlays, and secure encapsulation for cloud-managed traffic

• Experience with event loop frameworks (libev, libuv, or similar)

• Proficiency with debugging tools — GDB, strace, tcpdump, kernel logs, serial console

• Familiarity with Git, GitLab CI/CD, cross-compilation toolchains

• Understanding of WiFi standards (802.11ax/be) and wireless driver configuration

Preferred Skills

• Experience with Qualcomm IPQ series SoCs (IPQ5018, IPQ9574) and NSS/PPE data path

• Experience with Broadcom BCM series chipsets (BCM4908, BCM6750, BCM63178) and Memory Direct Engine (MDE) / hardware acceleration

• Knowledge of Atheros/QCA/BCM wireless chipsets and CFG80211/mac80211 driver architecture

• Knowledge of DOCSIS cable modem interaction and WAN interface management

• Experience with PCIe and USB subsystems in embedded Linux (device enumeration, power management, error recovery)

• Familiarity with eSIM/eUICC provisioning (LPA, GSMA SGP.22)

• Experience with carrier aggregation, NR5G NSA/SA, and multi-band cellular configurations

• Understanding of TR-069/TR-369 (USP) device management protocols

• Basic understanding of TR-181 data model for CPE device management and service configuration

• Experience with Kconfig-based build configuration

• Knowledge of flash storage considerations — wear leveling, persistent partitions, factory reset flows

• Familiarity with thermal management and power management (battery-powered CPE)

Tools & Technologies

• Languages: C, Shell scripting (sh/bash), Python (test automation)

• OS/Platform: OpenWrt (Linux 5.x/6.x kernel), ARM Cortex-A53/A73

• Frameworks: OpenSync, OVSDB, libev, protobuf-c, jansson (JSON)

• Chipsets: Qualcomm IPQ, Broadcom BCM, Atheros/QCA

• Networking: iproute2, iptables/nftables, ovsdb-server, hostapd/wpa_supplicant, GRE, IPsec

• Security: OpenSSL/mbedTLS, X.509 certificates, mTLS, certificate management

• Cellular: Qualcomm QCM/SDX modems, MHI, qcserial, AT+QENG/AT+COPS

• Protocols: IPv4, IPv6, DHCPv4/v6, DNS, MQTT, GRE, TLS 1.2/1.3

• Build: Make, Kconfig, OpenWrt feeds, cross-compilation (musl/glibc)

• Debug: GDB, valgrind, serial console, logpull analysis

• VCS/CI: Git, GitLab, merge request workflows

Nice to Have

• Experience working directly with ISP/MSO/OEM partners

• Exposure to hardware bring-up and board support package (BSP) development

• Experience with Agile/Scrum in a firmware development context

• Familiarity with SCTE/DOCSIS standards

• Understanding of TR-181 data model parameters for WAN management, WiFi configuration, and device monitoring

• Experience with GRE tunnel implementation for backhaul traffic in managed WiFi deployments

What You'll Work On

• Cellular failover/fallback state machines with sub-second transition handling

• LED indication logic for multi-WAN connectivity states

• Modem health monitoring and subsystem restart/recovery

• Internet reachability healthcheck frameworks

• Cloud-managed device configuration and telemetry reporting via MQTT

• Secure cloud connectivity using mTLS with X.509 certificate-based mutual authentication

• GRE tunnel management for cloud-redirected traffic

• Factory reset, firmware upgrade, and persistent storage management

• IPv4/IPv6 dual-stack network configuration, routing, and failover across DOCSIS and LTE interfaces

• WiFi radio configuration and performance optimization across Qualcomm / Broadcom platforms

• Kernel crash analysis and driver-level bug resolution

About Cognizant’s IoT Practice:

Intelligent, IoT-enabled products will soon result in the proliferation of data and disrupt virtually all industries. To be successful, both large and small companies must leverage IoT capabilities by designing modern products that fundamentally connect people with processes. Within Cognizant IOT, we engineer industry-aligned, IoT-enabled products that merge industry needs with human drivers. Our intelligent products will revolutionize experiences and result in exciting, transformative outcomes. Without human-centered thinking, connected products are just standalone things—but with it, our modern connected products facilitate a unified way of life enjoyed by all.

*Please note, this role is not able to offer visa transfer or sponsorship now or in the future*

  • Applications will be accepted until Aug31 , 2026
  • LI#- #LI-SC6

Compensation & Benefits

$104,000– $118,000 per year + Cost of Living Allowance

Bonus + Comprehensive Benefits

Additional Information

  • Onsite role
  • ⚠️ Visa sponsorship is not available now or in the future. Candidates requiring sponsorship will not be considered.

Benefits: Cognizant offers the following benefits for this position, subject to applicable eligibility requirements:

• Medical/Dental/Vision/Life Insurance

• Paid holidays plus Paid Time Off

• 401(k) plan and contributions

• Long-term/Short-term Disability

• Paid Parental Leave

• Employee Stock Purchase Plan

About Cognizant: 
Cognizant (Nasdaq: CTSH) is an AI Builder and technology services provider, bridging the gap between AI investment and enterprise value by building full-stack AI solutions for our clients. Our deep industry, process and engineering expertise enables us to build an organization’s unique context into technology systems that amplify human potential, drive tangible outcomes and keep global enterprises ahead in a fast-changing world. See how at cognizant.ai or @cognizant.

Additional employment information
Compensation information is accurate as of the date of this posting. Cognizant reserves the right to modify this information at any time, subject to applicable law.

Applicants may be required to attend interviews in person or by video conference. In addition, candidates may be required to present their current state or government issued ID during each interview.

Cognizant is an equal opportunity employer. Your application and candidacy will not be considered based on race, color, sex, religion, creed, sexual orientation, gender identity, national origin, disability, genetic information, pregnancy, veteran status or any other characteristic protected by federal, state or local laws.

Benefits that help you thrive and grow

Our benefits program is built with you in mind—so you can enjoy a fulfilling, balanced and healthy life.

a blue line drawing of a plant with leaves

Financial wellbeing

We regularly review market data to ensure compensation reflects the value you bring. Your benefits extend beyond pay and may include retirement plans, financial education, etc.

Stay Healthy Midnight Blue RGB

Physical and mental health

We empower you to prioritize your wellbeing through paid time off, flexible working where possible, healthcare plans, counselling, our Mental Health Allyship program and more. 

Build The Career You Want Midnight Blue RGB

Your career, your way

With 350,000+ roles at Cognizant, you’ll have opportunities explore new technologies, industries and locations—and build the skills you need to grow your career.

Making A Meaningful Impact Midnight Blue RGB

Real-world impact

Think about the biggest brands you rely on. Chances are, they rely on us to help strengthen their business. Here, you’ll turn bold ideas into solutions that improve lives everywhere.

Your path to Cognizant

Here’s what you can expect from our hiring process. Please keep in mind that it may vary by role and location. Explore our FAQs to learn more.

a person sitting at a table using a laptop

Step 1: Apply to the right opportunity

Find an open role that matches your skills and career goals and show us why you’re the person for the job. Don’t see the right opportunity? Consider joining our Talent Community.

a person holding a tablet and talking on the phone

Step 2: Connect with your recruiter

If one of our recruiters sees a fit, they’ll set up a short intro call to learn more about you and how your experiences and skills match the role.

a person smiling at a table with a laptop

Step 3: Show off your skills

If you and our team would like to continue the process, you’ll interview with our hiring team. Some roles may also require technical assessments and/or client interviews.

a group of people sitting around a table

Step 4: Decision time

Our team will then review each candidates’ potential to succeed in the role. This step may take some time because we want to find the right fit for both you and us—but you can count on us to keep you updated.

EMEA Alin
Over my 11-year Cognizant career, I’ve grown from being a Jr. Developer to an Engineering Director. With support from Cognizant and my mentors, I’ve also explored mobile development, data and AI. The opportunities here are endless.
Alin Turcu Engineering Director
CAN Brigitte
Cognizant is great for those wanting to make the world a better place, as we create solutions with top technology partners to address complex problems for our clients.
Brigitte Roy Director of Strategy Alliances
2
Cognizant offers me more than a job; it offers a community. We support each other, collaborate across borders and celebrate wins together. If you’re looking for a culture that values flexibility, diversity and growth, this is the place to be.
Laura Reynaud Lead Counsel
EMEA Elena
My managers and mentors have always been there to guide me, challenge me and give me the space and confidence to grow. When you have the right people around you, work becomes fun.
Elena Becerril Engagement Delivery Lead

Haven't yet found the right opportunity?

Get the latest updates on job opportunities, recruitment events and company news—tailored just for you!

Be in the know