Observed /fund and /fund/snapshot failures after deploy: hledger-overview.hs crashed with 'mismatched interface file versions (wanted 9084, got 9066)' when run under web.service. Root cause appears to be inherited GHC_PACKAGE_PATH/GHC_ENVIRONMENT contaminating nix-shell runhaskell execution. Fix by sanitizing env for overview command invocation.
Ava verified: last comment from human author documents shipping/deployment with concrete evidence. Moving to Verified.
Fixed in Omni/Fund/Overview.hs by sanitizing env before nix-shell script execution: use env -u GHC_PACKAGE_PATH -u GHC_ENVIRONMENT LEDGER_FILE=ledger.journal nix-shell ... . Deployed with web store path /nix/store/2zalghi5minxhwglw6w3829f9avzsxg6-web and verified /fund + /fund/snapshot return 200.