Heads-up: A single-line notice to let you know in advance

Today's English Expression 26/30 · Level: Meetings & Chat. All example sentences are created specifically for this post. They are not copied from actual repository comments, and the dates and versions are examples.

Table of Contents

• At a Glance
• 1. Meaning and Nuance
• 2. Example Sentences
• 3. Similar Expressions and Differences
• 4. Common Mistakes Made by Koreans
• 5. One-Line Practice
• Sample Answer
• Reference

At a Glance

1. Meaning and Nuance

Merriam-Webster defines the noun heads-up as "a message that alerts or warns someone to prepare for something." Originally, it was an exclamation shouted when something was falling from above, like "Watch your head!", but nowadays it is widely used in business to mean "this is coming soon, so please be aware".

The advantage of this expression is that it is a warning yet remains gentle. While Warning or Caution emphasizes danger, heads-up puts the consideration of "letting you know so you can prepare in advance" first. Therefore, it can be used for colleagues, maintainers, and users alike.

In open source, heads-up is frequently used in situations like these:

• When a large change to be merged soon might conflict with someone else's PR
• When default values or behavior change in the next release
• When you will be unable to reply for a while due to vacation or a business trip
• When the CI or test environment is temporarily unstable

Pay attention to spelling. When used as a noun, the hyphenated heads-up is the dictionary headword (a heads-up, thanks for the heads-up). When shouted as an exclamation of "Watch out!", it is written without a hyphen as Heads up!. Since Heads-up: used as a message heading is a noun, it is correct to include the hyphen.

2. Example Sentences

Situation 1: Slack Notice

Heads-up: I'm going to merge the API refactor tomorrow. If you have open PRs touching pkg/api, you'll probably need to rebase.

Situation 2: Announcing potential conflicts in a PR comment

Just a heads-up, #4100 changes the same function, so whichever lands second will need a rebase.

"whichever lands second" means "whichever one gets merged later." "land" will be covered in episode 29.

Situation 3: Giving advance notice of absence

Heads-up: I'll be offline next week. I'll pick up the remaining review comments when I'm back.

"pick up" means "to resume something that was paused."

Pairing Expression: The recipient of the notice

Thanks for the heads-up! I'll hold off on merging mine until yours is in.

"hold off on" means "to delay something."

3. Similar Expressions and Differences

• FYI (for your information): Meaning "letting you know for your reference," it is also used for information that does not require any preparation. Heads-up is better suited for upcoming events or things that may require action.
• PSA (public service announcement): An informal expression meaning an announcement to multiple people. Used when notifying an entire channel.
• Warning: ... Emphasizes the possibility of danger or loss. It is heavier, like a warning box in documentation.

4. Common Mistakes Made by Koreans

• Notice: Tomorrow I will merge the PR. Notice is a stiff heading, like an official document.
  • Corrected sentence: Heads-up: I'm planning to merge the PR tomorrow.
• I give you a heads up. The tense and article are awkward.
  • Corrected sentence: Just giving you a heads-up. Or Just a heads-up.
• Thank you for your heads up information. There is no need to add information.
  • Corrected sentence: Thanks for the heads-up.

5. One-Line Practice

Rewrite the following Korean sentence into a Slack message.

Just a heads-up. Starting with the next release, the default timeout will change from 30 seconds to 60 seconds.

Sample Answer

Heads-up: starting with the next release, the default timeout will change from 30s to 60s.

"starting with" means "from" and is frequently used before releases or versions. Writing "from the next release" also works fine.

TT's Word. Saying "I already told you" is much less pleasant to work with than "Let me let you know in advance."

Reference

• Merriam-Webster, "heads-up": https://www.merriam-webster.com/dictionary/heads-up