Ava Chow states on her own site that she primarily works on, and is a maintainer of, Bitcoin Core and the Hardware Wallet Interface project, and that she is currently an engineer at Blockstream. Her focus is wallet functionality and interoperability between different wallet software, which is the seam where a signing device from one vendor has to work with a wallet written by someone else.
Among her listed work is the migration of Bitcoin Core's wallet from Berkeley DB to SQLite, a change that removed a long-standing and awkward dependency, and a Bitcoin DNS seeder written in Rust. She also performs Guix builds for Bitcoin Core, previously Gitian, and publishes the results from her own fork so that anyone can compare them.
She is one of three people whose PGP keys are published in the Bitcoin Core repository for reporting security vulnerabilities, alongside Michael Ford and Niklas Gögge. She moderates the development sections of Bitcointalk and the Bitcoin Stack Exchange, and livestreams her work on Bitcoin Core weekly.