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tokens: based as closely as possible on standard physical principles. It includes winds and heating from young massive stars as well as feedback from SN explosions, the latter following the known physical processes that govern the different phases of SN remnants. We use the smoothed particle hydrodynamics (SPH) code SPHGal (Hu et al. 2014 ), an implementation that incorporates several improvements into the Gadget code (Springel 2005 ) to address some known SPH problems. Our approach is most similar to the stellar feedback in Agertz et al. ( 2013 ) and Agertz Kravtsov ( 2016 ), as well as the Feedback in Realistic Environment ( Fire ) project, presented in Hopkins et al. ( 2014 ) and used by Hopkins et al. ( 2012 , 2013 ), Muratov et al. ( 2015 ), and Su et al. ( 2016 ). We apply our stellar feedback to an isolated Milky Way-like galaxy within an isolated dark halo. The tools developed here are in use by the cosmological code in Choi et al. ( 2016 ). We break our approach into three parts: feedback from young, pre-SN stars, feedback from dying low-mass stars, and feedback from SN events. (1) We include the effects of stellar winds from young stars by transferring momentum to neighboring gas particles for the first few Myr. We also heat gas particles within the Strömgren sphere of young star particles, mimicking the effects of ionizing radiation from massive stars (see e.g., Renaud et al. 2013 ). (2) We transfer momentum from old, low-mass stars to the surrounding gas throughout several Gyr after a type II SN has occurred to imitate the slow winds from asymptotic giant branch (AGB) stars. (3) In our SN feedback model, we transfer SN energy to the closest gas particles to the SN event, each one receiving mass and energy according to a computed high-resolution evolution of SN remnants (SNR). Detailed very high resolution hydrodynamic simulations of SNR evolution (see Li et al. 2015 ), for details and a review) show that they pass through three successive phases: free expansion (FE), energy-conserving Sedov–Taylor (ST), and momentum-conserving snowplow (SP) (see also Kim Ostriker 2015 ; Martizzi et al. 2015 ; Walch Naab 2015 ). In our model, which we call the SP model, each neighboring gas particle receives energy following the physics governing the SNR phase in which the gas particles lie. If the gas particle lies within the radius of the ejecta-dominated FE phase, SN energy is transferred by conserving the ejecta momentum. If the gas particle lies outside the FE radius but within the radius of the adiabatic blast wave ST phase, SN energy is transferred 30% as kinetic energy and 70% as thermal energy. Finally, if the gas particle is beyond the ST radius and into the realm of the pressure-driven and momentum-conserving SP phase (Chevalier 1974 ), then part of the original SN energy is dissipated and only a fraction is transferred to the gas particle, with the thermal portion dissipating more quickly than the kinetic portion, following a prescription