Flexible circuits mountable in a standoff region between a chip carrier, e.g., a ball grid array (BGA) component, and a printed circuit board (PCB) of a surface-mount package are described. In an example, a flexible circuit includes holes to receive pins, e.g., solder balls, of the BGA component, and one or more conductive leads electrically connected to respective solder balls within the holes. The conductive leads may interconnect several solder balls within the standoff region, and may be electrically accessible through a test pad located laterally outward from the standoff region. Electrical signals may be monitored or driven through the test pad, and thus, the flexible circuit may be used as a debug tool for detecting and or correcting a design fault of the surface-mount package.