Senior Software Engineer, Backend (.NET)

Job Description

Are you ready to revolutionize the advertising industry?

At Cognitiv, we are not just another AdTech company—we are industry trailblazers redefining media buying with our Deep Learning Advertising Platform. Since 2015, we have harnessed the power of cutting-edge deep learning technology and data science to transform how brands connect with their customers. Our mission? To bring intelligence to advertising and deliver unparalleled precision, relevance, and impact at scale.

With our innovative platform, advertisers enjoy unprecedented flexibility—whether it is activating Dynamic Deals through their preferred DSP, leveraging our managed service DSP, or utilizing our industry-first ContextGPT product. As a part of Cognitiv, you will be at the forefront of AI-driven advertising solutions, driving change and achieving remarkable growth in a rapidly evolving industry.

Now, we’re growing—and looking for passionate engineers to help shape the future.

The Role

We’re hiring a Senior Software Engineer (Backend) to join the team building our next-generation, pixel-less ad targeting systems. You’ll design, build, and scale systems that power cutting-edge AI-driven advertising products, while improving and evolving existing platforms to meet growing business needs.

What You'll Do

Design, build, and own backend services in .NET Core on AWS.

Lead development of new versions of high-growth systems in pixel-less ad targeting.

Modernize and scale one of our critical legacy systems (internet crawling).

Collaborate with a small, senior team (2 SDE IIIs, 1 SDE II, CTO, and more senior hires coming).

Take full ownership of systems end-to-end, from design to production operations.

Drive improvements in performance, scalability, and developer productivity across the team and the engineering organization.

Who You Are

Experienced senior engineer – This isn’t your first rodeo. You’ve successfully delivered complex systems end-to-end and know how to balance speed with scalability.

Technical depth & breadth – Strong in .NET and a major cloud provider (AWS, Azure, or GCP), with a track record of designing and delivering production systems.

Ownership mindset – You don’t just maintain; you improve. You proactively take responsibility for entire systems.

Resilient & gritty – You thrive in ambiguity, manage competing priorities, and push through obstacles.

Strong communicator – You collaborate effectively across technical and non-technical stakeholders and resolve conflicts productively.

In-person collaborator – You want to work onsite MTW in Bellevue, WA.

Bonus Points If You Have

Startup experience (fast-moving, lean environments).

AdTech background.

Hands-on experience with our stack: .NET Core, AWS, RDS, Clickhouse.

What You'll Find at Cognitiv

Festiv – We make work fun with cross-team games, events, and creative team bonding.

Responsiv – You’ll be close to clients and leadership, influencing real outcomes.

Inclusiv – Diversity and individuality are celebrated across all levels.

Inventiv – We reward curiosity and embrace bold ideas.

Transformativ – We support your growth with training, mentorship, and flexibility.

Collaborativ – We operate across coasts, connected by purpose and teamwork.

Location & Compensation

Location: Bellevue (hybrid: 3 days in-office, 2 days remote)

Compensation is based on experience, skills, and other factors. Base salary is just one part of your total rewards at Cognitiv—you’ll also receive equity and a comprehensive benefits package.

Highlights include:

Medical, dental & vision coverage (some plans 100% employer-paid)

12 weeks paid parental leave

Unlimited PTO + Work-From-Anywhere August

Career development with clear advancement paths

Equity for all employees

Hybrid work model & daily team lunch

Health & wellness stipend + cell phone reimbursement

401(k) with employer match

Parking (CA & WA offices) & pre-tax commuter benefits

Employee Assistance Program

Comprehensive onboarding (Cognitiv University)…and more!