Fractional CTO / Technical Co - founder

Fractional CTO / Technical Co-founder

Full Spectrum Imaging (FSI)

Remote, US-based | ~5-10 hrs/week | Equity Earning Founder level role

Read This First

We are pre-funding. This role is equity-only until our first government contract or partnership revenue

closes (Active pursuits in progress). If you need a cash salary now, this role is not for you and we want

to be honest about that upfront.

If you are a senior PhD student, postdoc, early-career staff scientist, or industry engineer who is

technically excited about spectral X-ray imaging and wants meaningful equity in a startup with real

DOD/DHS/NIH momentum, this role could be exactly the right fit. You don't need to be an expert in

everything. You need technical aptitude in the right areas and an entrepreneurial mindset.

About Full Spectrum Imaging

Full Spectrum Imaging (FSI) is a Department of Homeland Security spinout developing IDIA, a

Randomized Foil Mask and Compressed Sensing reconstruction system that adds full spectral

information to existing X-ray and CT detectors. Our technology mounts to detector panels that hospitals,

security screeners, and industrial inspectors already use, unlocking material discrimination capabilities

that today require multi-million-dollar specialty equipment.

Where we are: TRL 3, moving toward our first prototype build. Active interest from Multiple large OEM,

Imaging, and government partners. Government customer pipeline across NIH, DHS, and NSF. Small

team with strong commercial leadership (CEO and operations) and a consulting bench of senior PhDs.

What we need: a technical leader who can own the prototype roadmap, run the day-to-day technical

decisions, and reduce our dependence on consultants who are not always available when we need

them.

The Role

You will lead the technical work to take FSI from TRL 3 to a validated prototype. Specifically:

• Lead the design of the Randomized Foil Mask: material selection, geometry, foil thicknesses, and

manufacturing path

• Direct the Compressed Sensing reconstruction algorithm work, in collaboration with our senior

consulting experts

• Own the development and execution of the test plan

• Build the prediction-chain software pipeline (SpekPy, NIST data, detector models) that turns

physics into testable predictions

• Serve as the technical voice in proposals, partner conversations, and customer engagements

• Help shape FSI's technical narrative across government agencies and OEM partners

What We Need Technically

You should have strong technical aptitude in most of the areas below. You do not need to be an expert

in all of them. We care more about depth in some and curiosity about the rest.

Strongly preferred (you are working-fluent in most of these)

• X-ray or CT physics: tube spectra, attenuation, detector response, reconstruction methods

• Compressed sensing theory and practice: sparse signal recovery, measurement matrices, TV

minimization, learned reconstruction methods

• Coded aperture imaging or hyperspectral reconstruction in any modality (optical hyperspectral

counts if you're willing to translate to X-ray)

• Material science fluency: K-edge behavior, mass attenuation coefficients, foil-material selection

• Python proficient enough to build and run physics simulation and analysis pipelines

Bonus if you have any of these (none required)

• Direct experience with SpekPy, xraylib, GATE, or other X-ray modeling tools

• Time at a medical imaging detector vendor, OEM, or national lab

• SBIR or other federal R&D experience

• Hands-on experience operating clinical or industrial X-ray equipment

• Publications in spectral CT, photon-counting detectors, coded aperture, or computational

imaging

Who We Are Looking For (Profile, Not Resume)

• Entrepreneurial. You want to build something, not write a paper about it. You're comfortable

making decisions with incomplete information.

• Mission-aligned. You see why spectral imaging on existing X-ray equipment matters for medical,

security, and industrial applications. The vision excites you.

• Self-directed. We don't have layers of management. You take a problem, work it, and come back

with progress. We help where needed.

• Honest about what you don't know. The intersection of skills here is rare. We expect the right

person to know some of it cold and learn the rest fast.

• Long-haul thinker. Equity-only compensation means you are betting on the upside. We want

partners who see the multi-year arc, not consultants billing hours.

Candidate Profiles That Fit

• Senior PhD students or recent PhDs in medical physics, applied physics, electrical engineering, or

biomedical engineering, particularly from groups working on spectral CT, photon counting, or

coded aperture imaging

• Postdocs in academic medical physics groups (Stanford, Mayo, Wisconsin, Chicago, Hopkins,

Duke, Arizona, UCL, Emory, UIUC et al) or national lab radiation detection groups

• Early-career staff scientists at detector vendors (Varex, Detection Technology, Hamamatsu,

Analogic, Teledyne) or OEMs (Siemens, Philips, GE, Canon)

• Engineers or scientists with hyperspectral imaging or compressed sensing backgrounds in optical

or other modalities who are excited to translate their work to X-ray

• Former medical device industry technical leads looking for a more entrepreneurial environment

Compensation Equity-only until FSI's first government contract or commercial revenue closes. Specific equity terms negotiated based on candidate background and time commitment. Cash compensation introduced as funding allows, with equity vesting continuing on a defined schedule.

Time commitment: 5-10 hours per week, flexible. We are looking for someone who can engage

meaningfully on technical work but who also desires the freedom of a fractional role.

What This Role Is Not

• Not a salaried role. We are pre-funding.

• Not a passive advisor seat. We need someone doing the work, not just advising on it.

• Not a heads-down research role. The CTO is FSI's technical voice in customer and partner

conversations.

• Not a one-shot consulting engagement. We are looking for a partner in building the company.

How to Apply

Send the following to ***email_hidden***:

• CV, LinkedIn profile, and/or Google Scholar link

• A short note (one page or less) telling us: which of the technical areas above you are strongest

in, which ones excite you to learn, and why an equity-only fractional CTO role at a TRL 3 spectral

imaging startup is interesting to you right now

• One example of self-directed technical work you're proud of, with a brief description of what

you owned

We respond to every qualified applicant within one week. First conversation: 30-minute video call with

the CEO to align on fit and vision. Second: 60-minute technical conversation with our consulting bench.

We aim to make decisions within three weeks of first contact.

Full Spectrum Imaging welcomes candidates from all backgrounds. We particularly encourage applications from candidates whose career path may not have followed a traditional academic-to-industry route, and from candidates earlier in their careers who bring strong technical aptitude and entrepreneurial drive.