We propose Check0-SSD, an intelligent SSD firmware to offer the best system-level fault-tolerance without performance degradation and lifetime shortening. Specifically, the SSD firmware autonomously removes transaction checkpointing, which eliminates redundant writes to the flash backend. To this end, Check0-SSD dynamically classifies journal descriptor/commit requests at runtime and switches the address spaces between journal and data regions by examining the host's filesystem layout and journal region information in a self-governing manner. Our evaluations demonstrate that Check0-SSD can protect both data and metadata with 89% enhanced storage lifetime while exhibiting similar or even better performance compared to the norecovery SSD.