# [`silk-env(1)`](/silk/docs/man/silk-env.1/) — Print `silk` CLI Environment

> NOTE: This is the Markdown source for the eventual man 1 page for `silk env`. The roff-formatted manpage should be generated from this content.

## Name

`silk-env` — print key environment variables consulted by the `silk` CLI.

## Synopsis

- `silk env [--json]`

## Description

`silk env` prints a list of key environment variables consulted by the `silk` CLI for configuration and debugging. The output is intended to be easy to paste into bug reports.

Use `--json` for tooling that needs the same environment facts without parsing
`NAME=value` lines.

## Output format

- One `NAME=value` entry per line.
- Unset variables are printed as `NAME=<unset>`.
- Variables set to an empty string are printed as `NAME=<empty>`.

JSON output is newline-terminated and contains `schemaVersion`, `command`, and
`vars`. Each variable entry includes `name`, `state` (`unset`, `empty`, or
`set`), and `value` (`null` when unset).

## Variables

The output includes, at minimum:

- `SILK_DEBUG_BACKEND` — enable backend debug output when set to a non-empty, non-`0` value.
- `SILK_DEBUG_BACKEND_ENUMS` — enable enum-lowering debug output.
- `SILK_STD_ROOT` — override stdlib root used to resolve `import std::...;`.
- `SILK_STD_LIB` — override stdlib archive used for linking (`libsilk_std.a`).
- `SILK_Z3_LIB` — override Z3 dynamic library path used for Formal Silk verification.
- `SILK_VERIFY_JOBS` — override the number of worker threads used for Formal Silk verification (default: auto; capped at 8).
- `SILK_PACKAGE_PATH` — package search path for bare-specifier imports and
 pathless manifest dependencies; dotted dependency keys map to slash
 directories. During package graph work, relative entries are resolved from
 the importing package root and then upward to the graph root.
- `SILK_SECURITY_PROVIDER` — default security provider mode for `silk build`,
 `silk check`, and `silk test` when `--security-provider` is omitted. Accepted
 values are `auto`, `platform`, and `builtin`.
- `SILK_GUIDE_DB` — override the guide database path used by [`silk guide`](/silk/docs/usage/guide-examples/).
- `SILK_GUIDE_PRINTER` — override the source printer command used by `silk guide --show` when `--printer` is not provided.
- `SILK_ELF_INTERP` — override the ELF `PT_INTERP` dynamic loader path used for `linux-x86_64` outputs when emitting dynamically-linked executables/shared libraries.
- `PREFIX` — installation prefix used for the system package search root (`PREFIX/lib/silk`) and as the default prefix for `silk build install` / `silk build uninstall` when `-p/--prefix` is not provided.
- `SILK_WORK_DIR` — override compiler work directory root (defaults to `.silk`).
- `SILK_CACHE_AUTO_HEAL` — enable/disable built-in healing of recognized managed cache entries during normal builds (default: enabled).
- `SILK_CACHE_AUTO_PRUNE` — enable/disable built-in pruning of recognized managed cache entries during normal builds (default: enabled).
- `SILK_CACHE_MAX_BYTES` — maximum size of recognized managed cache entries before size-based pruning runs (default: `2147483648`, or `2 GiB`; `0` disables size pruning).
- `SILK_CACHE_MAX_AGE` — maximum age of recognized managed cache entries before age-based pruning runs (default: `30d`; `0` disables age pruning).
- `SILK_CACHE_KEEP_RECENT` — preserve at least this many most-recently-used recognized managed cache entries during pruning (default: `64`).
- `SILK_REPL_HISTORY` — override REPL history path.
- `SILK_TEST_TIMEOUT_MS` — per-top-level-test process timeout in milliseconds (default: `30000`).
- `SILK_TEST_JOBS` — override the number of test processes run in parallel (default: `1`; `0` means auto; capped at 8). Overridden by `silk test --jobs`.
- `SILK_TEST_MAX_OUTPUT_BYTES` — maximum bytes of stdout/stderr captured per test process for diagnostics (default: `1048576`). Output beyond this limit is truncated.
- `SILK_RT_LIBDIR` — override search directory for bundled runtime archives (`libsilk_rt*.a`).
- `SILK_CC` / `CC` — select host C compiler for `silk cc` and `.c` inputs during `silk build`.
- `MANPAGER` / `PAGER` / `TERM` / `NO_COLOR` — paging and rendering configuration for `silk man` and diagnostic output.

## Examples

```sh
silk env
silk env --json
```

## See Also

- [`silk(1)`](/silk/docs/man/silk.1/)
- [`silk-cc(1)`](/silk/docs/man/silk-cc.1/)
- [`silk-build(1)`](/silk/docs/man/silk-build.1/)