diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f26b108..2c25638 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,3 +29,17 @@ jobs:
       - name: Build
         working-directory: site
         run: pnpm run build
+
+  installer:
+    runs-on: ubuntu-latest
+    name: Installer Tests
+    steps:
+      - uses: actions/checkout@v7
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v7
+        with:
+          node-version: '24'
+
+      - name: Test install.sh
+        run: node --test 'tests/*.test.mjs'
diff --git a/site/public/install b/site/public/install
index dfdcd9b..9a18bd2 100644
--- a/site/public/install
+++ b/site/public/install
@@ -20,38 +20,45 @@ error() {
     exit 1
 }
 
-# Check if uv is installed
+# Install uv (it brings Python and pywire into each new project) if missing
+FRESH_UV=
 if ! command -v uv >/dev/null 2>&1; then
     info "uv is not installed. Installing uv..."
     curl -LsSf https://astral.sh/uv/install.sh | sh
-    
-    # Try to source the cargo env if it exists (standard rust/uv install location)
-    if [ -f "$HOME/.cargo/env" ]; then
-        . "$HOME/.cargo/env"
-    elif [ -f "$HOME/.local/bin/env" ]; then
+
+    # Pick up uv in this shell (standard uv install locations)
+    if [ -f "$HOME/.local/bin/env" ]; then
         . "$HOME/.local/bin/env"
-    else
-        # Fallback: add common install paths to PATH for this session
-        export PATH="$HOME/.cargo/bin:$HOME/.local/bin:$PATH"
+    elif [ -f "$HOME/.cargo/env" ]; then
+        . "$HOME/.cargo/env"
     fi
-    
+    export PATH="$HOME/.local/bin:$HOME/.cargo/bin:$PATH"
+
     if ! command -v uv >/dev/null 2>&1; then
         error "Failed to install uv or add it to PATH. Please install uv manually: https://docs.astral.sh/uv/getting-started/installation/"
     fi
     success "uv installed successfully"
+    FRESH_UV=1
 else
     info "uv is already installed"
 fi
 
-# Run create-pywire-app
+# Run create-pywire-app: it scaffolds the project and installs pywire into it.
+# @latest skips uv's cached copy of the scaffolder.
 info "Running create-pywire-app..."
+status=0
 # `curl | sh` feeds this script on stdin, so reattach the terminal for
 # create-pywire-app's prompts, but only if there is one (CI, containers and
 # agents have no /dev/tty).
 if [ -t 0 ]; then
-    exec uvx create-pywire-app "$@"
+    uvx create-pywire-app@latest "$@" || status=$?
 elif (exec < /dev/tty) 2>/dev/null; then
-    exec uvx create-pywire-app "$@" < /dev/tty
+    uvx create-pywire-app@latest "$@" < /dev/tty || status=$?
 else
-    exec uvx create-pywire-app "$@"
+    uvx create-pywire-app@latest "$@" || status=$?
+fi
+
+if [ -n "$FRESH_UV" ]; then
+    info "uv was just installed: restart your shell (or run: . \"\$HOME/.local/bin/env\") so uv is on your PATH."
 fi
+exit "$status"
diff --git a/site/public/install.ps1 b/site/public/install.ps1
index f286fd1..a3abb02 100644
--- a/site/public/install.ps1
+++ b/site/public/install.ps1
@@ -36,4 +36,4 @@ if (-not (Get-Command "uv" -ErrorAction SilentlyContinue)) {
 
 # Run create-pywire-app
 Write-Info "Running create-pywire-app..."
-uvx create-pywire-app @args
+uvx create-pywire-app@latest @args
diff --git a/tests/install.test.mjs b/tests/install.test.mjs
new file mode 100644
index 0000000..03e6de3
--- /dev/null
+++ b/tests/install.test.mjs
@@ -0,0 +1,124 @@
+// Tests for the `curl -fsSL https://pywire.dev/install | sh` installer.
+// Each test runs the real script under `sh` with a sandboxed HOME and a PATH
+// of fake `uv`/`uvx`/`curl` binaries that log how they were called.
+import { test } from 'node:test'
+import assert from 'node:assert/strict'
+import { spawnSync } from 'node:child_process'
+import { chmodSync, mkdirSync, mkdtempSync, readFileSync, existsSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+
+const PUBLIC = new URL('../site/public/', import.meta.url).pathname
+const SCRIPT = join(PUBLIC, 'install')
+const SYSTEM_PATH = '/usr/bin:/bin'
+
+function exe(path, body) {
+  writeFileSync(path, `#!/bin/sh\n${body}\n`)
+  chmodSync(path, 0o755)
+}
+
+// A fake uv: `uv tool run ...`/`uvx ...` log their argv and whether stdin is a TTY.
+function fakeUv(dir, log) {
+  const body = `printf '%s\\n' "$(basename "$0") $*" >> ${log}
+if [ -t 0 ]; then echo stdin=tty >> ${log}; else echo stdin=notty >> ${log}; fi
+exit \${FAKE_UV_EXIT:-0}`
+  exe(join(dir, 'uv'), body)
+  exe(join(dir, 'uvx'), body)
+}
+
+function sandbox() {
+  const root = mkdtempSync(join(tmpdir(), 'pywire-install-'))
+  const home = join(root, 'home')
+  const bin = join(root, 'bin')
+  mkdirSync(home)
+  mkdirSync(bin)
+  return { root, home, bin, log: join(root, 'calls.log') }
+}
+
+function calls(box) {
+  return existsSync(box.log) ? readFileSync(box.log, 'utf8').trim().split('\n') : []
+}
+
+// Like `curl -fsSL https://pywire.dev/install | sh -s -- ARGS`: script on stdin.
+function runPiped(box, args = [], env = {}) {
+  return spawnSync('sh', ['-s', '--', ...args], {
+    input: readFileSync(SCRIPT),
+    env: { HOME: box.home, PATH: `${box.bin}:${SYSTEM_PATH}`, ...env },
+    encoding: 'utf8',
+  })
+}
+
+test('is served at /install', () => {
+  assert.ok(existsSync(SCRIPT), 'site/public/install must exist')
+})
+
+test('with uv installed, launches the latest create-pywire-app and passes args through', () => {
+  const box = sandbox()
+  fakeUv(box.bin, box.log)
+  const r = runPiped(box, ['my-app', '--yes'])
+  assert.equal(r.status, 0, r.stderr)
+  assert.ok(calls(box).includes('uvx create-pywire-app@latest my-app --yes'), calls(box).join('\n'))
+})
+
+test('without uv, installs uv first and then launches create-pywire-app', () => {
+  const box = sandbox()
+  // The fake astral installer (fetched by curl) drops uv into ~/.local/bin.
+  const fakeUvDir = join(box.root, 'uv-dist')
+  mkdirSync(fakeUvDir)
+  fakeUv(fakeUvDir, box.log)
+  exe(
+    join(box.bin, 'curl'),
+    `echo "curl $*" >> ${box.log}
+cat <<'EOF'
+mkdir -p "$HOME/.local/bin"
+cp ${fakeUvDir}/uv ${fakeUvDir}/uvx "$HOME/.local/bin/"
+EOF`,
+  )
+  const r = runPiped(box, ['my-app'])
+  assert.equal(r.status, 0, r.stderr)
+  const log = calls(box)
+  assert.ok(log.includes('curl -LsSf https://astral.sh/uv/install.sh'), log.join('\n'))
+  assert.ok(log.includes('uvx create-pywire-app@latest my-app'), log.join('\n'))
+  // The new shell has no uv on PATH until it is restarted, so say how to get it.
+  assert.match(r.stdout, /restart your shell/i)
+})
+
+test('fails loudly when uv cannot be installed', () => {
+  const box = sandbox()
+  exe(join(box.bin, 'curl'), 'exit 22')
+  const r = runPiped(box)
+  assert.notEqual(r.status, 0)
+  assert.match(r.stdout + r.stderr, /docs\.astral\.sh\/uv/)
+})
+
+test('propagates the create-pywire-app exit code', () => {
+  const box = sandbox()
+  fakeUv(box.bin, box.log)
+  const r = runPiped(box, [], { FAKE_UV_EXIT: '3' })
+  assert.equal(r.status, 3)
+})
+
+test('works without a terminal (CI, containers, agents)', () => {
+  const box = sandbox()
+  fakeUv(box.bin, box.log)
+  const r = spawnSync('setsid', ['sh', '-s'], {
+    input: readFileSync(SCRIPT),
+    env: { HOME: box.home, PATH: `${box.bin}:${SYSTEM_PATH}` },
+    encoding: 'utf8',
+  })
+  assert.equal(r.status, 0, r.stderr)
+  assert.ok(calls(box).includes('stdin=notty'), calls(box).join('\n'))
+})
+
+test('reattaches the terminal when piped to sh, so the wizard can prompt', () => {
+  const box = sandbox()
+  fakeUv(box.bin, box.log)
+  // `script` gives the command a real controlling terminal; the installer
+  // itself still arrives on a pipe, exactly like `curl ... | sh`.
+  const r = spawnSync('script', ['-qec', `cat ${SCRIPT} | sh`, '/dev/null'], {
+    env: { HOME: box.home, PATH: `${box.bin}:${SYSTEM_PATH}` },
+    encoding: 'utf8',
+  })
+  assert.equal(r.status, 0, r.stderr)
+  assert.ok(calls(box).includes('stdin=tty'), calls(box).join('\n'))
+})