UPD (Nov 30, 2023): I changed my mind, having understood the consequences and having gained a better understanding of the challenges this would present:

• multiple pip-compile runs with multiple python versions -> single requirements.txt #1326 (comment)
• Merge constraint contents for different envs #826 (comment)

Known closed and/or duplicate issues that may have some unique context/conversations:

• multiple pip-compile runs with multiple python versions -> single requirements.txt #1326
• Ability to Cross Compile #585
• Sync raises IncompatibleRequirements even when environment markers indicate the incompatible requirements to be irrelevant for the current platform #925
• Environment markers do not carry out to transitive dependencies #563
• Exclude package? #333
• pip-compile suffix numpy with +mkl #1471
• Using a combination of --generate-hashes, -c constraints.txt, --resolver=backtracking and --strip-extras doesn't currently work #1752
• platform_system not correctly respected #1793
• support multiple requirements in / txt  #532

I want to run pip-compile against the same set of requirements files under different envs (Python interpreters) and get a combined output.
Currently, it doesn't seem possible. Am I overlooking something?

Environment Versions

N/A

Steps to replicate

N/A

Expected result

resuling file is extended with extra entries

Actual result

resulting file is overridden