Show HN: DateTimeMate: A Golang lib and CLI for advanced date/time manipulation (github.com)

1 points by jftuga 1y ago ↗ HN

DateTimeMate is a new open-source Golang package and CLI tool I've developed to tackle common date and time manipulation challenges. It's designed to provide a robust, flexible solution for developers working with temporal data in Go or directly from the command line.

Key features:

* Precise duration calculations between arbitrary dates/times

* Date/time arithmetic with support for complex durations

* Periodic calculations with customizable repetition

* Flexible unit conversion for durations

* Date/time reformatting

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The CLI tool, dtmate, offers commands that mirror these core functionalities:

diff: Calculate time differences

dur: Perform date/time arithmetic

conv: Convert between duration units

fmt: Reformat date/time strings

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What sets DateTimeMate apart:

Intuitive syntax: The CLI accepts human-readable duration formats like "1 year 2 months 3 days 4 hours" as well as brief formats like "1Y2M3D4h".

Relative date shortcuts: Supports keywords like "now", "today", "yesterday", "tomorrow" for quick calculations.

Flexible unit handling: Converts between various time units, including sub-second precision (milliseconds, microseconds, nanoseconds).

Consistent year definition: Uses 365.25 days per year for accurate long-term calculations.

Dual-purpose design: Functions both as a standalone CLI tool and an importable Go package.

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CLI Example:

$ dtmate diff "2023-01-01 12:00:00" "2024-03-15 18:30:45"

1 year 2 months 14 days 6 hours 30 minutes 45 seconds

$ dtmate dur today "1Y 2M 3W 4D 5h 6m 7s" -a

2025-10-19 17:06:07

$ dtmate conv 4321s123456789ns hms.msusns

1h12m1s123ms456us789ns

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I built DateTimeMate to address the complexities often encountered in date/time manipulation, especially when dealing with mixed units or long-term calculations. It's particularly useful for tasks like:

* Project timeline calculations

* Age computations

* Event scheduling and planning

* Log analysis and time-based data processing

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The project is open-source and available on GitHub: https://github.com/jftuga/DateTimeMate

I'm keen to hear thoughts from the HN community. What other date/time challenges do you face in your projects? How could DateTimeMate be extended to better serve your needs?