  We report on the design and first year of operations of the DEdicated MONitor
of EXotransits and Transients (DEMONEXT). DEMONEXT is a 20 inch (0.5-m) robotic
telescope using a PlaneWave CDK20 telescope on a Mathis instruments MI-750/1000
fork mount. DEMONEXT is equipped with a $2048\times2048$ pixel Finger Lakes
Instruments (FLI) detector, a 10-position filter wheel with an electronic
focuser and $B$, $V$, $R$, $I$, $g'$, $r'$, $i'$, $z'$, and clear filters.
DEMONEXT operates in a continuous observing mode and achieves 2-4 mmag raw,
unbinned, precision on bright $V<13$ targets with 20-120 second exposures, and
1 mmag precision achieved by binning on 5-6 minute timescales. DEMONEXT
maintains sub-pixel ($<0.5$ pixels) target position stability on the CCD over 8
hours in good observing conditions, with degraded performance in poor weather
($<1$ pixel). DEMONEXT achieves 1-10% photometry on single-epoch targets with
$V<17$ in 5 minute exposures, with detection thresholds of $V\approx21$. The
DEMONEXT automated software has produced 143 planetary candidate transit light
curves for the KELT collaboration, and 48 supernovae and transient light curves
for the ASAS-SN supernovae group in the first year of operation. DEMONEXT has
also observed for a number of ancillary science projects including Galactic
microlensing, active galactic nuclei, stellar variability, and stellar
rotation.
