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Jayesh Patel

Posted on Mar 27

Swiss Ephemeris PHP: A 1:1 FFI Wrapper for Astronomical Precision in PHP 8.3+

#php #astronomy #laravel #opensource

Swiss Ephemeris PHP: A 1:1 FFI Wrapper for Astronomical Precision in PHP 8.3+

If you have ever built an astrology, astronomy, or ephemeris-based feature in PHP, you probably know the common trade-offs: CLI wrappers, slow process spawning, text parsing, or incomplete pure-PHP approximations.

I wanted something better.

So I built Swiss Ephemeris PHP — a framework-agnostic FFI wrapper for the Swiss Ephemeris C library, designed for PHP 8.3+, with prebuilt binaries to make installation easier across platforms.

This package is meant to stay close to the original Swiss Ephemeris API. No unnecessary abstraction. No external CLI process. No text-output parsing. Just direct native function access through PHP FFI.

What is Swiss Ephemeris?

Swiss Ephemeris is one of the most widely used astronomical calculation libraries for planetary positions, sidereal calculations, house systems, eclipses, and more.

It is trusted for high-precision astronomical and astrological work, which is exactly why it is so valuable in software that needs reliable celestial data.

Why I built this package

Most PHP solutions for Swiss Ephemeris fall into one of these categories:

CLI wrappers that call a binary and parse output
Pure PHP implementations that do not match the native library’s accuracy
Compiled PHP extensions that are harder to install and distribute

I wanted a package that gives PHP developers:

Direct access to the C library
Better performance than CLI-based approaches
Easy installation through Composer
Support for modern PHP applications
Compatibility with frameworks and plain PHP projects

That is the purpose of this wrapper.

What this package provides

Swiss Ephemeris PHP focuses on:

Direct FFI calls to the Swiss Ephemeris C library
A 1:1 mapping of the underlying API
Support for astronomical and astrological calculations
Prebuilt binaries for easier setup
Framework-agnostic usage
Laravel-friendly integration where needed

Why FFI matters

PHP FFI allows PHP to call native libraries directly.

That means you can:

Load a compiled shared library
Map C types, pointers, and structs
Call native functions without writing a PHP extension
Keep the development workflow simpler than compiling custom modules

For Swiss Ephemeris, this is a strong fit because it preserves the native behavior of the library while still letting PHP developers use it cleanly.

Example use case

A typical flow looks like this:

$sweph = new SwissEphFFI();

$jd = $sweph->swe_julday(2000, 1, 1, 12.0, SwissEphFFI::SE_GREG_CAL);

$xx = $sweph->getFFI()->new("double[6]");
$serr = $sweph->getFFI()->new("char[256]");

$sweph->swe_calc_ut(
    $jd,
    SwissEphFFI::SE_SUN,
    SwissEphFFI::SEFLG_SPEED,
    $xx,
    $serr
);

echo "Sun longitude: " . $xx[0] . "°";

That style keeps the wrapper close to the original Swiss Ephemeris behavior.

Key highlights

1:1 FFI wrapper for Swiss Ephemeris
PHP 8.3+ compatibility
Framework-agnostic design
Prebuilt binaries for supported platforms
Direct access to native astronomical functions
Suited for astrology, astronomy, and ephemeris-based applications

Where this fits best

This package is useful for projects like:

Astrology engines
Planetary position calculators
Vedic or sidereal computation tools
Astronomy dashboards
Calendar and panchanga systems
Scientific or educational applications

Installation

composer require jayeshmepani/swiss-ephemeris-ffi

After installation, configure your environment according to your platform and FFI requirements.

Laravel support

Even though the package is framework-agnostic, it can also be integrated into Laravel with service providers or facades for a more convenient developer experience.

Closing thoughts

Swiss Ephemeris PHP is built for developers who want the native Swiss Ephemeris library in PHP without compromising on architecture or forcing a heavy installation process.

If your project depends on accurate celestial calculations, this wrapper is designed to give you a cleaner path into Swiss Ephemeris from PHP.

References

jayeshmepani / Swiss-Ephemeris-PHP

PHP 8.3+ FFI wrapper for the Swiss Ephemeris C library with 1:1 API coverage, prebuilt binaries, and Laravel support.

Swiss Ephemeris PHP FFI

A strict, 100% precise, exact 1:1 FFI mapping of the Swiss Ephemeris C library for PHP 8.3+.

This wrapper gives you the exact API surface, structs, macro constants, and FFI pointers as defined in the original swephexp.h. Zero tolerance for omissions or high-level abstractions: every single calculation, planet ID, house system, sidereal mode, and eclipse check is strictly preserved for maximum astronomical precision.