In software engineering, the term “heuristic” and “proxy” are sometimes used in similar ways. For example

• Expertise in algorithms is a proxy for overall coding proficiency
• We can use the object’s name as a heuristic for its category

I get the sense that heuristic is used more commonly when the association is not absolute, whereas proxy is used more commonly to indicate a more certain relationship between two properties.

I can’t find any definitions that support using “heuristic” in this way at all, though proxy has a relevant definition from OED: “a figure that can be used to represent the value of something in a calculation” (definition accessed via Google).

When it would be more appropriate to use one of these terms versus the other? Am I conveying the colloquial usage of these terms correctly?