# walletkit-sqlite
Low-level encrypted SQLite support for WalletKit.
The crate provides safe Rust wrappers for connections, statements,
transactions, values, and sqlite3mc cipher operations. On native targets it
builds and statically links sqlite3mc; on WASM it delegates to
`sqlite-wasm-rs` and stores encrypted database pages in OPFS through the
SAH-pool VFS.
Browser hosts must run WalletKit in a dedicated worker and await
`walletkit_core::storage::initialize_persistent_storage()` before initializing
the credential store. The page key remains in Rust memory for the unlocked
store lifetime; persistent connections fail closed until the encrypted OPFS
VFS is installed.
## Native SQLite isolation
Native apps may also link system SQLite or another SQLite distribution. The
bundled sqlite3mc API has internal C linkage, and Rust uses only the
`walletkit_sqlite3_*` wrappers in `src/native_sqlite.c`. This prevents link
order from substituting the host engine for WalletKit's encrypted engine or
replacing the host engine with WalletKit's copy. New native FFI functions must
add a matching prefixed wrapper; visibility attributes alone do not isolate
symbols when linking static archives.
The amalgamation, cipher configuration, key encoding, and encrypted on-disk
format are unchanged. Cipher validation remains enabled. If a host previously
caused WalletKit to create a plaintext database, opening it read-write now
preserves its records and encrypts it in place with the supplied WalletKit key.
The migration checkpoints a plaintext WAL and switches to a rollback journal
because sqlite3mc cannot rekey in WAL mode; normal WAL policy is restored after
encryption. A read-only open fails without modifying plaintext data.