[rn7s2]

Problem

make install fails on a machine without /usr/local/bin:

Need sudo to write to /usr/local/bin
Password:
install: /usr/local/bin/INS@bHQl6a: No such file or directory
install: /usr/local/bin/INS@MhPIrz: No such file or directory
ln: /usr/local/bin/evo: No such file or directory
make: *** [install] Error 1

Cause

The install rule creates $(PREFIX)/bin only in its unprivileged branch. That mkdir -p is also the test for whether the directory is writable, so when it fails for lack of permission the sudo branch is taken without ever retrying it:

if [ -w $(PREFIX)/bin ] || mkdir -p $(PREFIX)/bin 2>/dev/null && [ -w $(PREFIX)/bin ]; then
  ...
else
  echo "Need sudo to write to $(PREFIX)/bin";
  sudo install -m 755 build/evo-agent $(PREFIX)/bin/evo-agent;   # dir never created

install(1) needs the destination directory to already exist — it writes a temp file (INS@xxxxxx) beside the target and renames it. With no /usr/local/bin, that temp file's path does not exist, hence the INS@…: No such file or directory errors. The ln after it fails for the same reason, and the non-zero exit aborts make.

This is the common case on macOS: Homebrew on Apple Silicon installs to /opt/homebrew and leaves /usr/local an empty, root-owned directory. On such a machine a fresh checkout could never complete the README.md quick start (make install, "enter your password if prompted") — the sudo path was the only one available, and it was broken.

Fix

Create the directory in the privileged branch too:

 	  echo "Need sudo to write to $(PREFIX)/bin"; \
+	  sudo mkdir -p $(PREFIX)/bin; \
 	  sudo install -m 755 build/evo-agent $(PREFIX)/bin/evo-agent; \

BSD install on macOS has no -D, so an explicit mkdir is the portable fix.

Verification

Reproduced the exact failure with a stand-in sudo that runs the command as the invoking user against a read-only PREFIX, then confirmed the patched rule completes:

Need sudo to write to /tmp/rootsim2/bin
$ ls -la /tmp/rootsim2/bin
lrwxr-xr-x  evo -> evo-swarm
-rwxr-xr-x  evo-agent
-rwxr-xr-x  evo-swarm
$ /tmp/rootsim2/bin/evo --version
evo-swarm 0.1.0

The direct-write branch (writable PREFIX) was already correct and still works.

Co-authored-by: EvoAgent evo@ruiqilei.com