Build arguments¶

The Dockerfile builds what its build arguments say. They are given to docker buildx bake with --set, or in a bake file, and castor gives them from a stack:

docker buildx bake --set default.args.PHP_VERSION=8.4.26                    # another PHP version
docker buildx bake --set default.args.EXTENSIONS="ctype tokenizer bcmath"   # other extensions
docker buildx bake --set default.args.TARGETS=node                          # only php-node.mjs and php-node.wasm

What to build¶

Argument	Default	What it is
`PHP_VERSION`	`8.5.12`	The PHP version to build.
`EXTENSIONS`	`calendar ctype dom mbstring simplexml xml xmlreader xmlwriter`	The extensions to build, separated by spaces (see Supported extensions). The libraries that they need (oniguruma for `mbstring`, libxml2 for the xml ones) are only built when an extension asks for them.
`TARGETS`	`web node`	The files to build: `web` for `php-web.mjs`, `php-web.wasm` and `php-sw.js`, `node` for `php-node.mjs` and `php-node.wasm`.
`MEMORY`	`128mb`	The memory of the WASM module, initial and maximum. `memory_limit` follows it, see Memory.
`ICU_DATA`	`all`	The data of ICU that intl links: `all` or `none` (see intl).
`OPCACHE`	`none`	When opcache compiles the PHP files, with PHP 8.5 and later: `none`, `runtime` or `precompiled` (see opcache).

What to embed¶

Argument	Default	What it is
`EMBED_AT`	empty	Where the embedded directory is in the WASM filesystem, `/app` for example. Nothing is embedded without it.
`WARMUP`	empty	A PHP file of the embedded directory, relative to it, and its arguments, separated by spaces: it runs when PHP is built, and what it writes in the directory is embedded too. For a cache that a framework makes with the paths of the WASM filesystem: `bin/console cache:warmup`.

The directory to embed is the embed named build context:

docker buildx bake --set default.contexts.embed=./my-app --set default.args.EMBED_AT=/app

The libraries¶

They are pinned, so that the same arguments always give the same build. The defaults are in docker/Dockerfile.

Argument	What it is
`EMSDK_VERSION`	The version of the Emscripten SDK that compiles everything, a tag of the emscripten/emsdk image.
`ICU_VERSION`	ICU, that intl uses, for example `78.3`.
`LIBICONV_VERSION`	GNU libiconv, that iconv uses, for example `1.19`.
`LIBJPEG_TURBO_VERSION`	libjpeg-turbo, that gd uses, for example `3.2.1`.
`LIBPNG_VERSION`	libpng, that gd uses, for example `1.6.59`.
`LIBSODIUM_VERSION`	libsodium, that sodium uses, for example `1.0.22`.
`LIBWEBP_VERSION`	libwebp, that gd uses, for example `1.6.0`.
`LIBXML_VERSION`	libxml2, that the xml extensions use.
`LIBZIP_VERSION`	libzip, that zip uses, for example `1.12.1`.
`ONIGURUMA_VERSION`	Oniguruma, that mbstring uses for regular expressions.
`OPENSSL_VERSION`	OpenSSL, that openssl uses, for example `3.5.9`.
`SQLITE_VERSION`	SQLite, that pdo_sqlite and sqlite3 use, for example `3.54.1`.
`SQLITE_YEAR`	The year of the release of `SQLITE_VERSION`, that is in its URL: for example `2026`.
`ZLIB_VERSION`	zlib, that zlib, libpng and libzip use, for example `1.3.2`.