Summary

rtk proxy bun run lint preserves exit code and total size, but changes line ordering versus raw command output.

In repro below, Bun command echo line ($ eslint ...) moves from first line to near the end.

Environment

• rtk: 0.20.0
• bun: 1.3.9
• project: ~/Projects/pricedrop/apps/pricedrop
• checked on: 18 February 2026

Reproduction

cd ~/Projects/pricedrop/apps/pricedrop
bun run lint > /tmp/raw.log 2>&1
rtk proxy bun run lint > /tmp/proxy.log 2>&1

Both commands return exit 1 and same size (641 lines, 49523 bytes), but:

diff -u /tmp/raw.log /tmp/proxy.log | sed -n "1,20p"

shows first-line removal:

- $ eslint entrypoints src test *.mjs *.ts --ignore-pattern .output

and tail shows this line near the end in proxy output.

Expected

rtk proxy should keep raw output order (strict fidelity mode).

Actual

One Bun metadata line is reordered.

Impact

Low severity, but breaks strict byte or line-order parity assumptions for machine checks on proxy output.