`pixi build --render-only`

[pavelzw]

Problem description

for debugging local builds, it would be nice to be able to pixi build --render-only. this is not yet possible, right @Hofer-Julian?

[Hofer-Julian]

Could you please clarify what this would do? With Rattler-Build, --render-only gives you the rendered recipe as JSON. Is that what you want here?

[pavelzw]

Exactly. This would have helped (a bit) debugging #5751

[pavelzw]

Tbh in rattler-build I would also like to have the "resolve dependencies step" only (human-readable) next to the json output

 ╭─ Running build for recipe: pixi-build-python-0.4.7-hb0f4dca_0
 │
 │ ╭─ Fetching source code
 │ │ No sources to fetch
 │ │
 │ ╰─────────────────── (took 0 seconds)
 │
 │ ╭─ Externally resolved dependencies recipe: pixi-build-python-0.4.7-hb0f4dca_0
 │ │ 
 │ │ Resolved build dependencies(pixi-build-python-0.4.7-hb0f4dca_0):
 │ │ ╭───────────────────────────────────┬───────────────┬─────────┬──────────────────────┬─────────────┬─────────────╮
 │ │ │ Package                           ┆ Spec          ┆ Version ┆ Build                ┆ Channel     ┆        Size │
 │ │ ╞═══════════════════════════════════╪═══════════════╪═════════╪══════════════════════╪═════════════╪═════════════╡
 │ │ │ gcc_linux-64                      ┆ gcc_linux-64  ┆ 15.2.0  ┆ h862fb80_21          ┆ conda-forge ┆   28.27 KiB │
 │ │ │ rust_linux-64                     ┆ rust_linux-64 ┆ 1.94.0  ┆ h185aabe_1           ┆ conda-forge ┆   11.05 KiB │
 │ │ │ _openmp_mutex                     ┆               ┆ 4.5     ┆ 20_gnu               ┆ conda-forge ┆   28.27 KiB │
 │ │ │ binutils_impl_linux-64            ┆               ┆ 2.45.1  ┆ default_hfdba357_102 ┆ conda-forge ┆    3.49 MiB │
 │ │ │ binutils_linux-64                 ┆               ┆ 2.45.1  ┆ default_h4852527_102 ┆ conda-forge ┆   35.45 KiB │
 │ │ │ gcc_impl_linux-64                 ┆               ┆ 15.2.0  ┆ he420e7e_18          ┆ conda-forge ┆   78.02 MiB │
 │ │ │ kernel-headers_linux-64           ┆               ┆ 6.12.0  ┆ he073ed8_6           ┆ conda-forge ┆    1.47 MiB │
 │ │ │ ld_impl_linux-64                  ┆               ┆ 2.45.1  ┆ default_hbd61a6d_102 ┆ conda-forge ┆  710.94 KiB │
 │ │ │ libgcc                            ┆               ┆ 15.2.0  ┆ he0feb66_18          ┆ conda-forge ┆ 1017.37 KiB │
 │ │ │ libgcc-devel_linux-64             ┆               ┆ 15.2.0  ┆ hcc6f6b0_118         ┆ conda-forge ┆    2.94 MiB │
 │ │ │ libgomp                           ┆               ┆ 15.2.0  ┆ he0feb66_18          ┆ conda-forge ┆  589.12 KiB │
 │ │ │ libsanitizer                      ┆               ┆ 15.2.0  ┆ h90f66d4_18          ┆ conda-forge ┆    7.72 MiB │
 │ │ │ libstdcxx                         ┆               ┆ 15.2.0  ┆ h934c35e_18          ┆ conda-forge ┆    5.58 MiB │
 │ │ │ libstdcxx-devel_linux-64          ┆               ┆ 15.2.0  ┆ hd446a21_118         ┆ conda-forge ┆   19.71 MiB │
 │ │ │ libzlib                           ┆               ┆ 1.3.2   ┆ h25fd6f3_2           ┆ conda-forge ┆   62.14 KiB │
 │ │ │ rust                              ┆               ┆ 1.94.0  ┆ h53717f1_0           ┆ conda-forge ┆  170.16 MiB │
 │ │ │ rust-std-x86_64-unknown-linux-gnu ┆               ┆ 1.94.0  ┆ h2c6d0dc_0           ┆ conda-forge ┆   35.18 MiB │
 │ │ │ sysroot_linux-64                  ┆               ┆ 2.39    ┆ hc4b9eeb_6           ┆ conda-forge ┆   40.10 MiB │
 │ │ │ tzdata                            ┆               ┆ 2025c   ┆ hc9c84f9_1           ┆ conda-forge ┆  116.34 KiB │
 │ │ │ zstd                              ┆               ┆ 1.5.7   ┆ hb78ec9c_6           ┆ conda-forge ┆  587.28 KiB │
 │ │ ╰───────────────────────────────────┴───────────────┴─────────┴──────────────────────┴─────────────┴─────────────╯
 │ │ Resolved host dependencies(pixi-build-python-0.4.7-hb0f4dca_0):
 │ │ ╭───────────────┬───────────────────────────────────────────┬─────────┬─────────────┬─────────────┬─────────────╮
 │ │ │ Package       ┆ Spec                                      ┆ Version ┆ Build       ┆ Channel     ┆        Size │
 │ │ ╞═══════════════╪═══════════════════════════════════════════╪═════════╪═════════════╪═════════════╪═════════════╡
 │ │ │ libgcc        ┆ libgcc >=15 (RE of [build: gcc_linux-64]) ┆ 15.2.0  ┆ he0feb66_18 ┆ conda-forge ┆ 1017.37 KiB │
 │ │ │ _openmp_mutex ┆                                           ┆ 4.5     ┆ 20_gnu      ┆ conda-forge ┆   28.27 KiB │
 │ │ │ libgomp       ┆                                           ┆ 15.2.0  ┆ he0feb66_18 ┆ conda-forge ┆  589.12 KiB │
 │ │ ╰───────────────┴───────────────────────────────────────────┴─────────┴─────────────┴─────────────┴─────────────╯
 │ │ Resolved run dependencies(pixi-build-python-0.4.7-hb0f4dca_0):
 │ │ ╭────────────────────────┬───────────────────────────────────────╮
 │ │ │ Name                   ┆ Spec                                  │
 │ │ ╞════════════════════════╪═══════════════════════════════════════╡
 │ │ │ Run dependencies       ┆                                       │
 │ │ │ libgcc                 ┆ >=15 (RE of [build: gcc_linux-64])    │
 │ │ │ pixi-build-api-version ┆ >=4,<5                                │
 │ │ │                        ┆                                       │
 │ │ │ Run constraints        ┆                                       │
 │ │ │ __glibc                ┆ >=2.17 (RE of [build: rust_linux-64]) │
 │ │ ╰────────────────────────┴───────────────────────────────────────╯
 │ │
 │ ╰─────────────────── (took 0 seconds)

[Hofer-Julian]

Having --render-only sounds good to me. For the output at stderr, let's discuss this first on the rattler-build side

[pavelzw]

prefix-dev/rattler-build#2363