I completely understand the purpose of execline but for server systems, which allocates more than 1 GB RAM regulary and running on modern x86 CPUs, saving such resources is not needed for us(!). So the comfort of porting stuff from existing oneshots overweights the computer resource usage for us(!).
Allow me to insist on a commonly misunderstood point here. execline is a dependency of s6 because s6 uses it internally; it is also much easier to autogenerate execline scripts than shell scripts (which is what s6-rc does). And execline is a good language to use in the context of very simple run scripts. But it is by no means necessary for any user of s6 to actually use execline or even understand it. Save for building s6, it is totally possible to use s6, write run scripts, etc., without ever knowing what execline does or even that it exists. What language you use in run scripts, or to glue your s6 installation with your business needs, is entirely your choice. By no means will you ever have to use execline yourself, even if execline commands and concepts are being used by s6 under the hood. -- Laurent