third_party/sqlite/{sqlite3.c,sqlite3.h,sqlite3ext.h} is the public-domain SQLite amalgamation (version 3.45.0, from sqlite.org), vendored and committed — unlike FFmpeg below, it's small (~9 MB source, no binaries) and public domain, so there's no license or size reason to auto-download it instead. It backs cli/memory_store.{hpp,cpp} (DroidHost's persistent agent-turn history — see ARCHITECTURE.md's "Persistent memory" extension phase). Compiled straight into the droidcli executable target (not the portable droidcli_core library) since it's real file I/O — a host concern per AGENTS.md's Golden rule, not a src/ concern.

To update: download a newer amalgamation from https://www.sqlite.org/download.html and replace the three files.

Droidcli uses FFmpeg (LGPL 2.1+) for media probe and decode. For commercial software, use dynamic linking (DLLs on Windows) — do not statically link GPL-enabled FFmpeg builds.

When CMake configures and FFmpeg is missing, it automatically downloads a shared FFmpeg package and extracts it under third_party/ffmpeg/.

Config knobs:

• DROIDCLI_FFMPEG_AUTO_DOWNLOAD=ON|OFF (default ON)
• DROIDCLI_FFMPEG_URL=<archive-url>
• DROIDCLI_FFMPEG_ROOT=<existing-prefix>
• DROIDCLI_FFMPEG_ALLOW_INSECURE_DOWNLOAD=ON|OFF (default ON; retries download with TLS verification disabled when certificate validation fails)

Extract a shared/dev FFmpeg build into:

third_party/ffmpeg/
  include/     libavcodec/, libavformat/, libswscale/, libavutil/, ...
  lib/         .lib / .a import libraries
  bin/         avcodec-*.dll, avformat-*.dll, ... (Windows runtime)

1. Download a shared FFmpeg build with dev files (e.g. BtbN FFmpeg Builds — ffmpeg-master-latest-win64-gpl-shared.zip or an lgpl shared variant if you need stricter licensing).
2. Copy include, lib, and bin into third_party/ffmpeg/.
3. Reconfigure CMake and rebuild.

Install dev packages or point DROIDCLI_FFMPEG_ROOT at a prefix with include/ and lib/.

This directory is listed in .gitignore — nothing under third_party/ffmpeg/ is pushed to GitHub.