Custom 35-Key Mechanical Keyboard PCB + QMK Firmware Developer

We are developing a proprietary wired industrial numpad for commercial inventory counting applications. We are seeking an experienced PCB designer and firmware developer to deliver a fully functional, production-ready custom keypad. This is a paid contract engagement with potential for ongoing support relationship. HARDWARE SPECIFICATIONS 35-key layout (7x5 matrix) Key functions and legends to be defined collaboratively based on our workflow requirements Reference layout: similar in concept to DC 2.5 Datacomputer with additional keys Final keymap will be provided by client prior to PCB layout finalization Wired only — no Bluetooth, no wireless Standard USB-C port (USB HID interface) Mechanical switches — tactile preferred (Gateron Brown, Kailh Brown, or equivalent — open to contractor recommendation) Custom dye-sublimation PBT keycaps with dual legends (inventory-specific hotkeys including VOID, ZONE, and others TBD) Compact footprint — designed for waist-mount handheld device, not desktop use Physical dimensions to be finalized collaboratively during Milestone 1 FIRMWARE SPECIFICATIONS QMK-based firmware VIA or VIAL compatibility required (browser-based remapping, no software install) Default keymap reflecting our 35-key layout as shipped Multiple programmable layers for macro/hotkey support Plug-and-play on Android (primary platform), iOS, Windows, Mac No drivers required DELIVERABLES PCB schematic files PCB layout files (Gerbers, production-ready) 3-5 assembled prototype boards with switches and keycaps installed QMK firmware source files VIA/VIAL configuration files Flashing instructions Basic test/validation report (all keys register, layers function, Android confirmed) CONTRACT STRUCTURE Milestone-based preferred: Milestone 1: Collaborative session to finalize keymap, physical dimensions, mounting points, and connector placement in coordination with our parallel case design process Milestone 2: Schematic review and approval Milestone 3: PCB layout + Gerber files Milestone 4: Prototype boards delivered Milestone 5: Firmware delivered + validated on Android CASE DESIGN COORDINATION Our 3D-printed case is being developed in parallel by our internal team. Contractor is expected to collaborate on physical PCB dimensions, switch plate approach, mounting point placement, and USB-C port position during Milestone 1 to ensure PCB and case designs are mutually compatible before either is finalized. VOLUME CONTEXT Initial prototype run: 3-5 units Production target: 500+ units annually Production will be handled via PCBA service (PCBWay/JLCPCB or equivalent) — contractor to provide production-ready files compatible with standard PCBA services TIMELINE Target: prototype boards in hand within 8 weeks of contract execution Firmware delivery concurrent with or immediately following prototype delivery BUDGET Please provide itemized quote for: PCB design (schematic + layout) Firmware development Prototype fabrication and assembly (3-5 units) Optional: ongoing support retainer for production questions SUBMISSION Please reply with: Portfolio samples of relevant mechanical keyboard or industrial keypad PCB work Itemized quote Proposed timeline Any questions or clarifying needs before quoting