Optomechanical systems, either naturally or through deliberate engineering, couple to multiple types of external stimuli, opening avenues to chip-scale sensor suites for many physical quantities. We are developing quantum optomechanical systems for primary sensing of temperature, pressure, and gas composition. The mass and intrinsic quantum noise of such systems provides embedded traceability to SI units. However, resolving quantum noise or molecular collision events with high precision in the presence of room-temperature thermal backgrounds remains an outstanding challenge. Overcoming this challenge requires both new nanophotonic optomechanical system designs and improved interrogation schemes. Postdoctoral researchers in our group will have the opportunity pursue either of these research avenues and explore new applications for our calibration-free, chip-scale sensors.