Kodak D-76 Developer is a classic multi-use black & white film developer.

D-76 provides full emulsion speed and excellent shadow detail with normal contrast, and produces fine grain with a variety of continuous-tone black-and-white films.

For greater sharpness, but with a slight increase in graininess, you can use a 1:1 dilution of this developer.

It yields a long density range, and its development latitude allows push processing with relatively low fog.