Upgrading PHP 7.4 to PHP 8.0 for Zephir Parser (Unable to initialize module)

php -v yeilds the following output:

PHP 8.0.28 (cli) (built: Feb 14 2023 18:32:57) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.28, Copyright (c) Zend Technologies
    with Zend OPcache v8.0.28, Copyright (c), by Zend Technologies

ls -l /etc/alternatives/*php* yeilds the following output:

lrwxrwxrwx 1 root root 15 Apr 17 20:51 /etc/alternatives/php -> /usr/bin/php8.0
lrwxrwxrwx 1 root root 22 Apr 17 20:51 /etc/alternatives/php-config -> /usr/bin/php-config8.0
lrwxrwxrwx 1 root root 38 Apr 17 20:51 /etc/alternatives/php-config.1.gz -> /usr/share/man/man1/php-config8.0.1.gz
lrwxrwxrwx 1 root root 31 Apr 17 20:51 /etc/alternatives/php.1.gz -> /usr/share/man/man1/php8.0.1.gz
lrwxrwxrwx 1 root root 18 Apr 17 20:51 /etc/alternatives/phpize -> /usr/bin/phpize8.0
lrwxrwxrwx 1 root root 34 Apr 17 20:51 /etc/alternatives/phpize.1.gz -> /usr/share/man/man1/phpize8.0.1.gz

Following the documentation on Github, I run the following:

/etc/alternatives/phpize
./configure --with-php-config=/etc/alternatives/php-config
make
make install

This creates the SO in the ./modules directory and places it into the /usr/lib/php/20200930 directory.

I then vim /etc/php/8.0/cli/php.ini and add extension=zephir_parser.so before saving and closing.

Running php -v now gives me:

PHP Warning:  PHP Startup: zephir_parser: Unable to initialize module
Module compiled with module API=20190902
PHP    compiled with module API=20200930
These options need to match
 in Unknown on line 0
PHP 8.0.28 (cli) (built: Feb 14 2023 18:32:57) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.28, Copyright (c) Zend Technologies
    with Zend OPcache v8.0.28, Copyright (c), by Zend Technologies

I have PHP 7.4 installed on the target machine but its not picking up the PHP 8 config? Any help appreciated.

Update: Truncated output of the make install:

libtool: install: cp ./.libs/zephir_parser.so /home/someuser/zephir

/php-zephir-parser/modules/zephir_parser.so
libtool: install: cp ./.libs/zephir_parser.lai /home/someuser/zephir/php-zephir-parser/modules/zephir_parser.la
libtool: finish: PATH="/root/.nvm/versions/node/v18.7.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/sbin" ldconfig -n /home/someuser/zephir/php-zephir-parser/modules
[...]
Installing shared extensions:     /usr/lib/php/20200930/
Installing header files:          /usr/include/php/20200930/

Even putting the absolute path to the SO throws the same build version error:

extension=/usr/lib/php/20200930/zephir_parser.so

php -v

PHP Warning:  PHP Startup: zephir_parser: Unable to initialize module
Module compiled with module API=20190902
PHP    compiled with module API=20200930
These options need to match
 in Unknown on line 0
PHP 8.0.28 (cli) (built: Feb 14 2023 18:32:57) ( NTS )
Copyright (c) The PHP Group
Zend Engine v4.0.28, Copyright (c) Zend Technologies
    with Zend OPcache v8.0.28, Copyright (c), by Zend Technologies

source https://stackoverflow.com/questions/76038932/upgrading-php-7-4-to-php-8-0-for-zephir-parser-unable-to-initialize-module