logger idea

api.go

package tlog

// import (...)

func WithTags(ctx context.Context, pairs ...string) context.Context {
	// turn these pairs into a bunch of [][2]string, shove into the Context
}

func Print(ctx context.Context, f string, v ...interface{}) {
	tags := fromContext(ctx)
	line := strings.Builder{}
	// build line...
	Output(2, line.String())
}

// etc...

type Logger struct {}

func New(...) *Logger {
	// use the functional options pattern because we're breaking compatability with everything, hard
}

func (l *Logger) Print(ctx context.Context, f string, v ...interface{}) {
	//...
}

func FromContext(ctx context.Context) *log.Logger {
	// close over the provided context and provide a very unconfigurable logger, like the stackdriver package.
	// A compatability niceity.
}

use.go

package main

func mydumbfunction(ctx context.Context) error {
	ctx := tlog.WithTags(ctx, "today", "tuesday")
	tlog.Println(ctx, "doing mydumbfunction")
	// ...
	return nil
}