Name

Pacer and Amazon Q autocomplete

In short

Amazon Q Developer CLI, now Kiro CLI, includes the autocomplete popover that came from Fig, together with an AI chat and agents, and it asks you to sign in. Pacer is only the popover. It started from the autocomplete code that Amazon released as open source, and it removes the sign-in and the AI.

Where they differ

Sign-in
Amazon Q and Kiro CLI need an account. Pacer needs none.
AI
Amazon Q and Kiro CLI add AI chat and agents. Pacer has no AI; its suggestions come from spec files and your own shell.
Network
Pacer makes no network calls while you type. Only pacer update and pacer doctor use the network, and only when you run them.
Local features
Pacer adds changed files first, branches with their last commit, ranking by what you run in each repo, a guard for risky commands, pacer stats, and pacer doctor.

Which to choose

If you use Amazon Q or Kiro CLI mostly for the popover, Pacer gives you that without an account. If you use their AI chat, keep them for that, but do not run both popovers in the same shell. The guide for moving from Kiro CLI or Amazon Q shows how to switch.