the trace is:
error: while evaluating the attribute 'buildCommand' of the derivation 'home-manager-generation' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/pkgs/build-support/trivial-builders.nix:7:14:
while evaluating the attribute 'text' of the derivation 'activation-script' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/pkgs/build-support/trivial-builders.nix:7:14:
while evaluating 'mkCmd' at /home/zhenhao/.nix-defexpr/channels/home-manager/modules/home-environment.nix:395:17, called from undefined position:
while evaluating the attribute 'data' at /home/zhenhao/.nix-defexpr/channels/home-manager/modules/lib/dag.nix:91:37:
while evaluating the attribute 'data' at /home/zhenhao/.nix-defexpr/channels/home-manager/modules/lib/dag.nix:85:9:
while evaluating the attribute 'data' at undefined position:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:75:45, called from undefined position:
while evaluating the attribute 'value' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:336:9:
while evaluating the option `home.activation.checkFilesChanged.data':
while evaluating the attribute 'isDefined' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:373:5:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:362:9:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:456:7:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:28, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:17:
while evaluating 'dischargeProperties' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:415:25, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:349:62:
while evaluating the attribute 'value' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:234:44:
while evaluating 'concatMapStrings' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/strings.nix:31:25, called from /home/zhenhao/.nix-defexpr/channels/home-manager/modules/files.nix:213:12:
while evaluating the attribute 'home.file' at undefined position:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:75:45, called from undefined position:
while evaluating the attribute 'value' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:336:9:
while evaluating the option `home.file':
while evaluating the attribute 'isDefined' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:373:5:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:362:9:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:456:7:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:28, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:17:
while evaluating 'dischargeProperties' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:415:25, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:349:62:
while evaluating 'dischargeProperties' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:415:25, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:421:11:
while evaluating the attribute 'content' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:500:14:
while evaluating 'foldr' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/lists.nix:52:20, called from /home/zhenhao/.nix-defexpr/channels/home-manager/modules/programs/vscode.nix:91:9:
while evaluating 'fold'' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/lists.nix:55:15, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/lists.nix:59:8:
while evaluating the attribute 'extensions' at undefined position:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:75:45, called from undefined position:
while evaluating the attribute 'value' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:336:9:
while evaluating the option `programs.vscode.extensions':
while evaluating the attribute 'mergedValue' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:368:5:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:368:32, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:368:19:
while evaluating 'merge' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/types.nix:256:20, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:371:8:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/types.nix:257:35, called from undefined position:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/lists.nix:116:29, called from undefined position:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/types.nix:259:23, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/lists.nix:116:32:
while evaluating the attribute 'optionalValue' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:375:5:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:362:9:
while evaluating the attribute 'values' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:456:7:
while evaluating anonymous function at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:28, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:348:17:
while evaluating 'dischargeProperties' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:415:25, called from /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/modules.nix:349:62:
while evaluating the attribute 'value' at /nix/store/x8vj04ycchwckh0xqlhnrzx9k0g7m6ih-nixos-19.09.2229.d7843c8add6/nixos/lib/types.nix:263:40:
while evaluating anonymous function at /nix/store/8x90sd5m33zhz96z72zgydgy11nc6wb2-source/lib/customisation.nix:77:32, called from /home/zhenhao/.config/nixpkgs/home.nix:13:25:
while evaluating 'makeOverridable' at /nix/store/8x90sd5m33zhz96z72zgydgy11nc6wb2-source/lib/customisation.nix:67:24, called from /nix/store/8x90sd5m33zhz96z72zgydgy11nc6wb2-source/lib/customisation.nix:77:41:
anonymous function at /nix/store/8x90sd5m33zhz96z72zgydgy11nc6wb2-source/pkgs/misc/vscode-extensions/default.nix:1:1 called with unexpected argument 'scala-lang', at /nix/store/8x90sd5m33zhz96z72zgydgy11nc6wb2-source/lib/customisation.nix:69:16
I will try to install it via the OS to see if the overlay works