  We describe the new spectroscopic data reduction pipeline for the
multi-object MMT/Magellan Infrared Spectrograph. The pipeline is implemented in
idl as a stand-alone package and is publicly available in both stable and
development versions. We describe novel algorithms for sky subtraction and
correction for telluric absorption. We demonstrate that our sky subtraction
technique reaches the Poisson limit set by the photon statistics. Our telluric
correction uses a hybrid approach by first computing a correction function from
an observed stellar spectrum, and then differentially correcting it using a
grid of atmosphere transmission models for the target airmass value. The
pipeline provides a sufficient level of performance for real time reduction and
thus enables data quality control during observations. We reduce an example
dataset to demonstrate the high data reduction quality.
