diff --git a/AGENTS.md b/AGENTS.md
index 497ebd1..ed865fc 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -54,6 +54,7 @@ RESTIC_PASSWORD=example-local-password
 RESTIC_PASSWORD2=example-b2-password
 B2_APPLICATION_ID=xxxx
 B2_APPLICATION_KEY=yyyy
+B2_EXECUTABLE_PATH=/opt/homebrew/bin/b2
 SATORU_RESTIC_B2_REPOSITORY=b2:bucket-name:repo-prefix
 ```
 
diff --git a/cmd/satoru/config.go b/cmd/satoru/config.go
index af78cae..b794c99 100644
--- a/cmd/satoru/config.go
+++ b/cmd/satoru/config.go
@@ -30,6 +30,7 @@ const defaultConfigBody = `# Satoru configuration file
 # Backblaze B2 credentials (application key format):
 # B2_APPLICATION_ID=your-application-key-id
 # B2_APPLICATION_KEY=your-application-key
+# B2_EXECUTABLE_PATH=/opt/homebrew/bin/b2
 #
 # B2 restic repository target:
 # SATORU_RESTIC_B2_REPOSITORY=b2:your-bucket:satoru-repo
diff --git a/cmd/satoru/scanner.go b/cmd/satoru/scanner.go
index 457399d..4e77cc4 100644
--- a/cmd/satoru/scanner.go
+++ b/cmd/satoru/scanner.go
@@ -17,25 +17,33 @@ import (
 )
 
 func (a *app) runtimeChecks() []webui.RuntimeCheck {
-	tools := []string{"restic", "rsync", "ssh", "b2"}
+	tools := []struct {
+		Name     string
+		ExecPath string
+	}{
+		{Name: "restic", ExecPath: "restic"},
+		{Name: "rsync", ExecPath: "rsync"},
+		{Name: "ssh", ExecPath: "ssh"},
+		{Name: "b2", ExecPath: b2ExecutablePath()},
+	}
 	out := make([]webui.RuntimeCheck, 0, len(tools))
 	for _, name := range tools {
-		path, err := exec.LookPath(name)
+		path, err := exec.LookPath(name.ExecPath)
 		if err != nil {
-			out = append(out, webui.RuntimeCheck{Name: name, Installed: false, Details: "not found in PATH"})
+			out = append(out, webui.RuntimeCheck{Name: name.Name, Installed: false, Details: "not found: " + name.ExecPath})
 			continue
 		}
 		details := path
-		if name == "b2" && a.b2ProbeNote != "" {
+		if name.Name == "b2" && a.b2ProbeNote != "" {
 			details = details + " | " + a.b2ProbeNote
 		}
-		out = append(out, webui.RuntimeCheck{Name: name, Installed: true, Details: details})
+		out = append(out, webui.RuntimeCheck{Name: name.Name, Installed: true, Details: details})
 	}
 	return out
 }
 
 func (a *app) runStartupB2Probe(ctx context.Context) {
-	if _, err := exec.LookPath("b2"); err != nil {
+	if _, err := exec.LookPath(b2ExecutablePath()); err != nil {
 		a.b2ProbeNote = "startup probe skipped: b2 cli not installed"
 		a.b2InitReady = false
 		a.b2InitRepo = ""
@@ -105,6 +113,10 @@ func clipDetail(v string, max int) string {
 	return v[:max-3] + "..."
 }
 
+func b2ExecutablePath() string {
+	return getenvDefault("B2_EXECUTABLE_PATH", "b2")
+}
+
 func runSSHHello(ctx context.Context, site store.Site) (string, string) {
 	target := fmt.Sprintf("%s@%s", site.SSHUser, site.Host)
 	cmdCtx, cancel := context.WithTimeout(ctx, 10*time.Second)