Find and understand the customer real problem, no just listen what say want, like Henry Ford say “if i hear what my customer want, i must make faster horses”
“Kiss Method”, is not a comertial method i learn it from my Fortran IV teacher sound a little agressive but i must say i agree, when i sit in my chair to begin a code i “ear” his words “kiss is the real solution” (Keep It Simple Stupid), i find a lot of code that is 5% solving the problem and 95% trash to make it look bigger and complex.
Usage of Filesystem like datastorage (in nonpublic places)
Webservices
BackEnd expert