Meaning:
“灰度” means “grayscale,” and “发布” means “release.” Often used in the scenario of releasing the new function or service of softwares, this term refers to a release process involving a smooth transition. During the transitional period, the original version is available, and a new version is deployed as a “canary” (As canaries are extremely sensitive to methane gas, mine workers used to carry them for timely detection of gas leaks). Also called “a canary release,” it is a deployment pattern where a small percentage of traffic is diverted to the canary version. This technique lets you test a release on a small subset of users, mitigating the impact of any given bug. Canary releasing also allows you to quickly roll back to a known good version in the event of an unexpected error.
Example:
A: 你们的新版软件上线了吗？
Nǐmen de xīnbǎn ruǎnjiàn shàngxiàn le ma？
Have you released the new version of your software?
B: 上周已经灰度发布了，还没正式上线。
Shàngzhōu yǐjīng huīdù fābù le，hái méi zhèngshì shàngxiàn。
We launched a grayscale release last week and are yet to release it officially.