Prototype Manager Jobs in California (NOW HIRING)

Please note that we are unable to provide visa sponsorship for this position.
Recruiting agencies: Proper Voltage does not accept unsolicited candidate submissions. Please do not contact any employees directly unless you have an existing engagement with the company.
About Proper Voltage
Proper Voltage is unlocking the next generation of battery technology across robotics, data centers, and defense.
We're building intelligent battery systems that make advanced chemistries (sodium-ion, lithium-titanate, lithium-silicon) work in products that were never designed for them. Humanoid robots can upgrade power systems without redesigning their entire platform. Data centers get safer, cheaper backup power. Drones and autonomous vehicles get higher energy density without lengthy integration cycles.
If you want to work on hard engineering problems that matter this is the place.
Job Overview
The NPI Prototype Procurement Manager owns fast-turn prototype sourcing during new product development. When engineering needs a part quoted and built in days, not weeks, this role makes it happen, and makes sure the part we source for a prototype build doesn't quietly become a bad default for production.
This role reports to the Director of Supply Chain and works closely with engineering, our prototype contract manufacturers, and our production sourcing team. Prototype CMs are good at turning parts fast; they are not set up to decide which of those parts should become a real production supplier, or to catch when a rushed sourcing decision is costing us on markup or quality risk down the line. That decision needs a dedicated owner on our side.
We are building this role now because the gap is already showing up in real costs: parts moving slower than they should, and markups on prototype-CM-sourced parts that we're paying today without anyone tracking whether that's the right long-term call.
Scope
Fast-turn sourcing: for parts that are strategic, long-lead, or clearly headed toward production, you run the RFQ and sourcing decision directly rather than letting a prototype CM default-source it under time pressure.
Prototype-to-production tracking: for parts a prototype CM sources on our behalf, you track what was bought, from whom, and at what cost, and you flag early which of those should transition to a qualified production supplier instead of carrying forward by default.
Cost visibility: you own should-cost tracking on new parts as designs stabilize, flagging anything trending over target early enough to actually do something about it.
This role sits specifically in the handoff between early prototype builds and production. Production commodity strategy, supplier negotiation, and cost-out on qualified production parts stay with our sourcing team. Day-to-day material tracking and expediting once a part is in production stays with our materials team. This role owns the messy middle: prototype-stage sourcing decisions that determine what production inherits.
This role starts as an individual contributor working in close partnership with engineering.
Who this role is for
You have direct experience sourcing prototype and early-production parts in a hardware environment, working shoulder to shoulder with engineering while designs are still moving. You're comfortable quoting and placing an order on a part that might change again next week.
You think past the next build. When a prototype shop sources a part fast, you're the person asking whether that supplier, that price, and that quality level are good enough to carry into production, or whether it needs to change before it's too late to change cheaply.
You're comfortable working through and around a contract manufacturer's own sourcing team rather than owning a factory floor yourself. You know how to get a CM's buyer to move fast for you, and you know when to route around them and source directly.
You have a cost-conscious streak. You notice when a markup looks high and you're willing to do the work to find out if it's justified.
You are comfortable in early-stage environments where the playbook is still being written, and where this specific handoff between prototype and production sourcing hasn't had a dedicated owner before.
This role is not a fit for

• You are looking to own production commodity strategy or long-term supplier negotiation. That sits with our sourcing team.
• You are looking to own day-to-day material tracking and expediting once parts are in production. That sits with our materials team.
• You need stable designs and a locked BOM to work effectively. This role lives in the period before that's true.
• You would find a startup operating tempo frustrating.

What you'll do
Prototype sourcing

• Run quick-turn RFQs and place orders directly for strategic, long-lead, or clearly production-bound parts during prototype builds.
• Partner with engineering embedded in design reviews and build planning, understanding what's changing and what's stabilizing.
• Manage supplier relationships for quick-turn shops separate from our production supplier base.

Prototype-to-production handoff

• Track every part sourced by a prototype CM on our behalf: supplier, cost, and whether it's fit to carry forward.
• Flag parts that should transition to a qualified production supplier early enough to make the change before it's expensive.
• Hand off qualified parts and supplier context cleanly to our production sourcing team, with a clear paper trail rather than tribal knowledge.

Cost visibility

• Own should-cost tracking on new parts as designs stabilize, flagging cost overruns early.
• Identify where prototype CM markups are worth the convenience and where a direct sourcing decision would save real money.

Cross-functional partnership

• Partner with our production sourcing team on the handoff for parts moving from prototype to production.
• Partner with our materials team on build timing and part availability during prototype phases.
• Partner with engineering on design-for-sourcing input while parts are still changeable.

Required Qualifications

• 4+ years in procurement or sourcing supporting new product development in a hardware or industrial product environment.
• Direct experience with fast-turn/quick-turn sourcing (rapid prototyping shops, quick-turn machining or fab, low-volume electronics).
• Comfort working alongside a contract manufacturer's own sourcing team rather than owning a factory floor directly.
• Experience evaluating whether a prototype-sourced part or supplier is fit to carry into production.
• Ability to operate independently and build process where none exists yet.

Preferred Qualifications

• Experience in battery, energy storage, power electronics, or other hardware-adjacent categories.
• Should-cost or cost estimation experience on early-stage or immature designs.
• Experience transitioning parts from a prototype or contract manufacturer to a qualified production supplier.
• Early-stage startup experience.

Compensation & Benefits

• Base salary of $155,000 to $175,000, plus equity.
• Health, dental, and vision insurance.
• Flexible PTO with a generous holiday policy.
• Carlsbad, CA strongly preferred. Open to fully remote for the right candidate. Occasional travel to contract manufacturers.

Ready to work on power systems that matter? Let's talk.