Server setup in the app

cmd/byre/check.go

@@ -0,0 +1,101 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+
+	"g.fc.run/ai/byre/internal/tailscale"
+)
+
+const (
+	needRequired = "required"
+	needAgent    = "agent"
+	needOptional = "optional"
+)
+
+type check struct {
+	Name     string `json:"name"`
+	Need     string `json:"need"`
+	For      string `json:"for"`
+	OK       bool   `json:"ok"`
+	Fix      string `json:"fix"`
+	Blocking bool   `json:"blocking"`
+}
+
+func checks() []check {
+	return []check{
+		gitCheck(),
+		tailscaleCheck(),
+		command("claude", needAgent, "Claude models", "curl -fsSL https://claude.ai/install.sh | bash, then run claude once to sign in"),
+		command("codex", needAgent, "GPT models", "brew install --cask codex, then run codex once to sign in"),
+		command("agy", needAgent, "Gemini models", "brew install --cask antigravity-cli, then run agy once to sign in"),
+		command("npx", needOptional, "reviewers' Playwright browser tools", "brew install node"),
+		appCheck("Google Chrome", needOptional, "browser tools for agents and reviewers", "brew install --cask google-chrome"),
+	}
+}
+
+func gitCheck() check {
+	c := check{Name: "git", Need: needRequired, For: "worktrees, snapshots and merges", Fix: "xcode-select --install"}
+	path, err := exec.LookPath("git")
+	// /usr/bin/git is a stub that offers to install the Command Line Tools when they're missing.
+	c.OK = err == nil && (path != "/usr/bin/git" || exec.Command("xcode-select", "-p").Run() == nil)
+	return c
+}
+
+func tailscaleCheck() check {
+	problem := tailscale.Problem(context.Background())
+	return check{Name: "Tailscale", Need: needRequired, For: "the server's HTTPS address and identity", OK: problem == "", Fix: problem}
+}
+
+func command(name, need, purpose, fix string) check {
+	_, err := exec.LookPath(name)
+	return check{Name: name, Need: need, For: purpose, OK: err == nil, Fix: fix}
+}
+
+func appCheck(name, need, purpose, fix string) check {
+	_, err := os.Stat("/Applications/" + name + ".app")
+	return check{Name: name, Need: need, For: purpose, OK: err == nil, Fix: fix}
+}
+
+func markBlocking(cs []check) bool {
+	agentOK := false
+	for _, c := range cs {
+		agentOK = agentOK || (c.Need == needAgent && c.OK)
+	}
+	ready := true
+	for i, c := range cs {
+		cs[i].Blocking = !c.OK && (c.Need == needRequired || (c.Need == needAgent && !agentOK))
+		ready = ready && !cs[i].Blocking
+	}
+	return ready
+}
+
+func checkCmd() {
+	cs := checks()
+	ready := markBlocking(cs)
+	out, err := json.Marshal(struct {
+		Ready  bool    `json:"ready"`
+		Checks []check `json:"checks"`
+	}{ready, cs})
+	if err != nil {
+		fatal("encode checks", "err", err)
+	}
+	fmt.Println(string(out))
+}
+
+func requireChecks() {
+	cs := checks()
+	if markBlocking(cs) {
+		return
+	}
+	fmt.Println("byre can't run on this Mac yet. It needs git, Tailscale, and at least one of claude, codex and agy:")
+	for _, c := range cs {
+		if c.Blocking {
+			fmt.Printf("  %s: %s\n", c.Name, c.Fix)
+		}
+	}
+	os.Exit(1)
+}

cmd/byre/install.go

@@ -44,6 +44,7 @@ const plistTemplate = `<?xml version="1.0" encoding="UTF-8"?>
 `
 
 func installCmd() {
+	requireChecks()
 	exe, err := os.Executable()
 	if err != nil {
 		fatal("find executable", "err", err)

cmd/byre/main.go

@@ -16,6 +16,8 @@ func main() {
 		serveCmd(os.Args[2:])
 	case "install":
 		installCmd()
+	case "check":
+		checkCmd()
 	case "run":
 		runCmd(os.Args[2:])
 	default:
@@ -24,7 +26,7 @@ func main() {
 }
 
 func usage() {
-	fmt.Fprintln(os.Stderr, "usage: byre serve | byre install | byre run [--resume ID]")
+	fmt.Fprintln(os.Stderr, "usage: byre serve | byre install | byre check | byre run [--resume ID]")
 	os.Exit(2)
 }