Implements the Indexer interface using Google's BTree library with full thread safety via sync.RWMutex. Provides ordered iteration (ascend/descend), range queries, and a custom iterator that supports forward/reverse traversal and seek. The implementation is clean, self-contained, and could be extracted as a reusable in-memory BTree index for any Go project needing ordered key-value storage with concurrent access.

Implements a Watcher with a fixed-capacity circular buffer (eventQueue) for buffering key change events. It provides thread-safe push/pop operations and a goroutine that sends events to a channel. The design handles overflow by overwriting oldest events. This is a generic, reusable event buffering pattern that can be extracted for any system requiring a bounded, non-blocking event queue with a consumer goroutine.

Provides efficient binary encoding and decoding of log records using variable-length integers (varint) for compact representation. Includes encodeLogRecord, decodeLogRecord, encodeHintRecord, and decodeHintRecord functions. The encoding is optimized for size and speed, with a fixed header size calculation. These functions are self-contained (depend only on standard library and a buffer pool) and can be reused in any project needing a compact binary record format for key-value pairs with metadata.

Exposes Go's internal runtime memhash function via //go:linkname, providing a fast, hardware-accelerated hash function for byte slices and strings. This is a non-obvious optimization trick that avoids the overhead of standard library hashers. The implementation is minimal and can be directly reused in any Go project requiring a high-performance hash function for in-memory data structures.