What was the yellow card about?

The yellow card just identifies you as a connecting passenger, so that downstream airport staff can direct you to the Connections CBSA booths. But, as discussed a bit upthread, YVR has no OSS, nor will it for a long time without renovations. If you have Nexus, there's no point to the connections process in YVR. We skip it, use Nexus, exit with YVR-destined passengers and go back in to domestic from the "Outside".

Of course, we never have checked baggage, so I'm not sure if that is a problem if you have checked baggage and don't go through the Connections hallway.

Thanks - I've never seen this before. I will be transiting YVR international-domestic in a few weeks, so this is useful information.

You'll find YVR employees at the top of the stairs near "connections" signs handing them out.

It seems that it has been fixed now lmao

Not only that, there are times you CANNOT use Nexus.

Bringing commercial goods across the border, for example

Even bringing chocolate. You go to the normal line, you are fine. Go to the nexus one and declare, they send you to secondary. And miss your connection at YYZ.

And yesterday at 9:30am (!!) in YYZ the lineup was still 30+ people deep with 2 agents. Went downstairs through the regular NEXUS lane and then re-cleared security (zero lineup) -- much faster than standing in the OSS line and then taking the bus. Also had the advantage of walking by the transfer desk so I could get myself on standby for an earlier flight to YOW.

I want this to work so much, and when it first opened and there was no lineup I was pretty excited about saving some time and security re-clear. But the setup they have at YYZ is such a disaster (too few agents, no NEXUS machine, bus instead of walking) they might as well shut it down and save the cost of operating it.

Meanwhile, last night in YUL, there were 4 agents waiting for me - zero people in line - and I went from a US gate to a domestic gate in less than 10 minutes.

Comments like yours and moos from others have me plotting to transit YUL instead of YYZ when flying to exotic Winter destinations like BOS. These trips are unfortunately necessary even though they violate one of my personal travel rules.

Yet another reason to avoid YYZ.

Not anymore. If you say Yes to food, they will process that right where all the customs agents are, so you can skip secondary

I am hoping/assuming that sooner or later, Nexus machines and a walkway will appear there. There is already one from Domestic to International. Does not seem so impossible to go back the other way

So nexus entry is different for each entry? I came back via YUL and used the machine for nexus and it never asked for food. It had a very generic question if I have anything to declare and I said no which would be the same as using the card. Am I missing something?

The Nexus machine asks if you are over your limit or have something to declare. It isn't food specifically but it will stop you.

I know in YYZ, there is the Nexus agent you flash your card when you pass. Last time I declared food (Chicago Pizza) I was processed before going down the escalator so I just walked out as per normal