MeerFish implements a Fisher forecasting framework tailored to upcoming large-sky single-dish HI intensity mapping surveys such as those planned with the MeerKAT telescope and its successor within the SKAO project. The code models survey specifications and expected statistical uncertainties to compute Fisher matrices and forecast parameter constraints on cosmological observables derived from 21 cm intensity maps. It provides modules to define survey configurations, cosmological and nuisance parameters, and the associated signal and noise models needed for forecasting survey performance. MeerFish outputs predicted errors on power spectrum measurements and derived parameters, enabling quantitative assessment of survey design choices and scientific reach.

halomod calculates cosmological halo model and HOD quantities. It is built on HMF (ascl:1412.006); it retains that code's features and provides extended components for the halo model, including numerous halo bias models, including scale-dependent bias, basic concentration-mass-redshift relations, and several plug-and-play halo-exclusion models. halomod includes built-in HOD parameterizations and halo profiles, support for WDM models, and all basic quantities such as 3D correlations and power spectra, and also several derived quantities such as effective bias and satellite fraction. In addition, it offers a simple routine for populating a halo catalog with galaxies via a HOD. halomod is flexible and modular, making it easily extendable.