<p>Reclaimed timber often exhibits warp and deformation that compromise conventional CAD-driven joinery workflows. Existing scan–register–cut routines correct global pose but leave the joint geometry fixed, forcing nominal interfaces onto non-nominal material and producing misfits in form-fitting connections. These workflows also depend on time-consuming full registration and manual CAD re-modeling, where each correction propagates across the assembly—an impractical step in real fabrication environments. This paper introduces Fit by Feedback, a robot-centric adaptive fabrication framework that integrates sensing, geometric analysis, and machining in a continuous loop. The system performs fast, minimal scanning, completing full acquisition in under 10 s, derives a scan-informed CAM model, and morphs joint operations directly to the measured geometry of each beam and its neighbors. Rather than editing CAD models, the workflow adapts the toolpaths themselves, allowing each connection to conform to the as-found material. Experiments show millimeter-level accuracy in groove following, pocket compatibility, and joint engagement across moderately warped beams. The results demonstrate that closed-loop toolpath adaptation can restore joint precision and assembly fit without heavy registration, re-modeling, or reconditioning, offering a practical pathway for integrating warped reclaimed timber into robotic fabrication.</p>