Given the following YAML: ```yaml name: env-bug base: core22 version: '0.1' summary: foo description: bar grade: devel confinement: strict apps:   hello-world:     environment:       plain: $LD_LIBRARY_PATH       bracketed: ${LD_LIBRARY_PATH}       prepended: foo:${LD_LIBRARY_PATH}       complex: ${LD_LIBRARY_PATH:-Foo}       snapcrafts: ${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}     command: echo parts:   my-part:     plugin: nil     override-build: |       touch ${CRAFT_PART_INSTALL}/foo       chmod 555 ${CRAFT_PART_INSTALL}/foo ``` Snapcraft sets the default top-level `environment.LD_LIBRARY_PATH` to: ```yaml # snap/meta.yaml environment   LD_LIBRARY_PATH: ${SNAP_LIBRARY_PATH}${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH} ``` But there's no shell to interpret that expansion: ```shell $ snap run --shell my-snap-name.hello-world -c "printenv plain" /var/lib/snapd/lib/gl:/var/lib/snapd/lib/gl32:/var/lib/snapd/void $ snap run --shell my-snap-name.hello-world -c "printenv bracketed" /var/lib/snapd/lib/gl:/var/lib/snapd/lib/gl32:/var/lib/snapd/void $ snap run --shell my-snap-name.hello-world -c "printenv prepended" foo:/var/lib/snapd/lib/gl:/var/lib/snapd/lib/gl32:/var/lib/snapd/void $ snap run --shell my-snap-name.hello-world -c "printenv complex" $ snap run --shell my-snap-name.hello-world -c "printenv snapcrafts" $ ``` As far I can tell, there's only simple string replacement happening.