Update readme

README.md

@@ -8,19 +8,20 @@ Linux).
 
 ## Install
 
-Download the native binary for your platform from a release, or build from
-source:
+Download the pre-built binary for your platform and make it executable.
+
+Using **curl**:
 
 ```shell
-git clone https://github.com/JMR-dev/bootstrap_dev_env.git
-cd bootstrap_dev_env
-make build           # builds ./bootstrap_environment for the host
+curl -Lo bootstrap_environment "https://github.com/JMR-dev/bootstrap_dev_env/releases/latest/download/bootstrap_environment-$(uname -s | tr '[:upper:]' '[:lower:]')-$(uname -m | sed 's/x86_64/amd64/; s/aarch64/arm64/; s/arm64/arm64/')"
+chmod +x bootstrap_environment
 ```
 
-To produce native binaries for all four supported targets at once:
+Using **wget**:
 
 ```shell
-make build-all       # writes dist/bootstrap_environment-{linux,darwin}-{amd64,arm64}
+wget -O bootstrap_environment "https://github.com/JMR-dev/bootstrap_dev_env/releases/latest/download/bootstrap_environment-$(uname -s | tr '[:upper:]' '[:lower:]')-$(uname -m | sed 's/x86_64/amd64/; s/aarch64/arm64/; s/arm64/arm64/')"
+chmod +x bootstrap_environment
 ```
 
 ## Usage
@@ -42,3 +43,23 @@ Flags:
   that backs the `firecracker()` zsh wrapper.
 
 Package lists live in `packages.go`. Edit and rebuild.
+
+## Build from Source
+
+If you prefer to build the tool yourself, or if you are making custom modifications:
+
+1. Clone the repository:
+   ```shell
+   git clone https://github.com/JMR-dev/bootstrap_dev_env.git
+   cd bootstrap_dev_env
+   ```
+
+2. Build for the current host platform:
+   ```shell
+   make build           # builds ./bootstrap_environment for the host
+   ```
+
+To cross-compile binaries for all supported targets at once:
+```shell
+make build-all       # writes dist/bootstrap_environment-{linux,darwin}-{amd64,arm64}
+```

docs/future-state.md

@@ -0,0 +1,5 @@
+# Future State
+
+- which guard/check at end of binary
+- unit test suite
+- early program end if nothing found to do

pkgmgr.go

@@ -199,6 +199,11 @@ func resolveSystemPkgs(names []string) ([]string, []string) {
 
 // isSystemPkgInstalled queries the host package manager.
 func isSystemPkgInstalled(pkg string) bool {
+	// If 'which $pkg' returns a value, the package's command is available, so skip it.
+	if r, ok := probe([]string{"which", pkg}, 0); ok && r.ExitCode == 0 {
+		return true
+	}
+
 	switch pkgMgr {
 	case "dnf":
 		r, ok := probe([]string{"rpm", "-q", pkg}, 0)