The flag of the rusty red metal mailbox was up. Just like that, my end-of-day, wiped-out mood evaporated. I had been hot, tired and hungry five minutes agoor “hangry,” a word my daughter recently brought home from college. Swerving off the road and onto the shoulder, I anticipated carbohydrate rejuvenation.

In our rural neighborhood, mailboxes have multiple functions and signal codes. They’re neighborly drop boxes; if the flag is up on a Wednesday or Thursday afternoon, for instance, it means our mailbox is full of bread, rolls, buns or some unexpected kind of floury bonus. New mail carriers are often confused.

It’s not a home-delivery CSA. We have chickens, and our neighbors own a local bakery. It’s as simple as that. For nearly 30 years, we’ve been trading our eggs for their bread. When the kids were younger, we used to walk the trails between the houses, bearing these gifts. It was never just about eggs for bread. But the toddlers have become grown-ups, and our neighbors are about to become grandparents. The weekly mailbox exchange is pure barter efficiency.

On Thursday or Friday morning, I put aside our best dozen eggs and box them up to get them ready for a hike to the end of the road for Saturday morning mailbox delivery. (One rarely discussed concern of small-flock chicken farmers is the constant need for sturdy empty egg cartons. About every other full moon, a shopping bag of egg cartons appears on the front porch; you’ve got to love the next-door egg carton fairy, too.) On slow coop weeks, we might have to postpone our own weekend quiche or loaf of pound cake, as a deal’s a deal. We’re usually halfway through whatever goodies we just picked up when we deliver our eggs, anyway.

Some mornings, we’re slicing up challah bread or toasting beer bread, while sometimes we’re functioning as a test kitchen for a prospective new item on the menu. The darker and the more rustic the offering is, the better. There’s nothing wrong with day-old ciabatta, either. I think we even get a few new-employee, half-risen practice loaves, too. It’s all good.

Over the years, bread and eggs have had their panic moments, their own 15 minutes of infamy. Remember the Atkins Diet, the pox on carbohydrates? Recall the caution notices of too many egg yolks? But fresh is fresh and local is better, so we continue our exchangerain or shine, year in, year out, no matter what the day’s health trends dictate.

This week’s mailbox surprise might have been the best ever: A soft, chewy, fragrant loaf of chocolate babka made me scuttle dinner plans immediately. I slalomed down the driveway, digging my fingers into chocolaty, doughy bliss. I’ve got to tell the chickens that they might have to step it up for the weekend.