cmd/enter/run.go (1)

30-33: ⚠️ Potential issue | 🟠 Major

Variable shadowing: err on line 31 shadows the err from the if-init on line 30.

Change the assignment on line 31 from := to = to use the outer error variable instead of creating a shadow:

Fix

 	if _, err := os.Stat(nixosMarker); err != nil {
-		err := fmt.Errorf("%v is not a valid NixOS system", opts.RootLocation)
+		err = fmt.Errorf("%v is not a valid NixOS system", opts.RootLocation)
 		log.Error(err)
 		return err
 	}

cmd/install/install.go (1)

550-552: ⚠️ Potential issue | 🟠 Major

Fix remaining variable shadowing issues: Lines 550 and 564 redeclare err instead of reassigning it.

Line 550 declares a new err variable that shadows the outer err declared at line 540. Line 564 does the same. Use assignment (=) instead of declaration (:=) to reuse the outer variable:

Line 550 fix

-		if err := installBootloader(s, mountpoint); err != nil {
+		if err = installBootloader(s, mountpoint); err != nil {
 			return err
 		}

Line 564 fix

-			err := setRootPassword(s, mountpoint)
+			err = setRootPassword(s, mountpoint)

cmd/activate/user.go (1)

79-83: ⚠️ Potential issue | 🟡 Minor

err on line 82 shadows the outer err declared on line 42.

The err := on line 82 creates a new variable that shadows the outer err from the function scope. While this doesn't cause a functional issue (the block immediately returns), it should be fixed for code clarity and to satisfy the Go shadowing linter.

Proposed fix

	if status == "timeout" || status == "failed" || status == "dependency" {
-		err := fmt.Errorf("restarting nixos-activation.service failed with status %s", status)
+		err = fmt.Errorf("restarting nixos-activation.service failed with status %s", status)
		log.Error(err)
		return err
	}

internal/system/ssh.go (1)

345-353: ⚠️ Potential issue | 🔴 Critical

Data race: goroutine writes to the shared err variable concurrently.

Line 348 assigns to the outer err (from Run on line 270) inside a goroutine that runs concurrently with session.Run(fullCmd) on line 355, which also assigns to err. Previously, := would have scoped a local err to the goroutine; now both paths race on the same variable.

Proposed fix — use a local variable inside the goroutine

 	go func() {
 		for sig := range sigCh {
 			if s := osSignalToSSHSignal(sig); s != "" {
-				if err = session.Signal(s); err != nil {
+				if sigErr := session.Signal(s); sigErr != nil {
-					log.Warnf("failed to forward signal '%v': %v", s, err)
+					log.Warnf("failed to forward signal '%v': %v", s, sigErr)
 				}
 			}
 		}
 	}()

cmd/option/option.go (1)

187-195: ⚠️ Potential issue | 🟠 Major

Use a local err variable in the evaluator closure to prevent data race when called concurrently.

The closure captures and mutates the outer optionMain scope's err variable. Since optnix's TUI can invoke EvaluatorFunc from multiple goroutines, concurrent writes to the shared err create a data race. The fix is straightforward:

Proposed fix

 var evaluator option.EvaluatorFunc = func(optionName string) (string, error) {
-	var value *string
-	value, err = nixosConfig.EvalAttribute(optionName)
+	value, err := nixosConfig.EvalAttribute(optionName)
 	realValue := ""
 	if value != nil {
 		realValue = *value
 	}
 	return realValue, err
 }