composer requirements can't be met

[oschonrock]

php7.1

# composer install --ignore-platform-reqs
Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Installation request for composer/installers v1.0.22 -> satisfiable by composer/installers[v1.0.22].
    - composer/installers v1.0.22 requires composer-plugin-api 1.0.0 -> no matching package found.
  Problem 2
    - Installation request for yiisoft/yii2-composer 2.0.3 -> satisfiable by yiisoft/yii2-composer[2.0.3].
    - yiisoft/yii2-composer 2.0.3 requires composer-plugin-api 1.0.0 -> no matching package found.
  Problem 3
    - composer/installers v1.0.22 requires composer-plugin-api 1.0.0 -> no matching package found.
    - webfatorial/fuel-db-seeder dev-develop requires composer/installers ~1.0 -> satisfiable by composer/installers[v1.0.22].
    - Installation request for webfatorial/fuel-db-seeder dev-develop -> satisfiable by webfatorial/fuel-db-seeder[dev-develop].

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.

Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.

[cebe]

the composer.lock file is too old for your version of composer. i.e. it contains depdendencies on plugins that do not work with the latest version. you should try composer update instead.

[oschonrock]

Thanks. Made some progress with

composer update --ignore-platform-reqs

but then got

# composer install --ignore-platform-reqs
Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Nothing to install or update
Generating autoload files
> php oil r install
        Made writable: /usr/home/oliver/php-orm-benchmark/fuel/app/cache
        Made writable: /usr/home/oliver/php-orm-benchmark/fuel/app/logs
        Made writable: /usr/home/oliver/php-orm-benchmark/fuel/app/tmp
        Made writable: /usr/home/oliver/php-orm-benchmark/fuel/app/config

Fatal error: Uncaught Error: Call to undefined method Error::shutdown_handler() in /usr/home/oliver/php-orm-benchmark/fuel/core/bootstrap.php:77
Stack trace:
#0 [internal function]: {closure}()
#1 {main}
  thrown in /usr/home/oliver/php-orm-benchmark/fuel/core/bootstrap.php on line 77
PHP Fatal error:  Uncaught Error: Call to undefined method Error::shutdown_handler() in /usr/home/oliver/php-orm-benchmark/fuel/core/bootstrap.php:77
Stack trace:
#0 [internal function]: {closure}()
#1 {main}
  thrown in /usr/home/oliver/php-orm-benchmark/fuel/core/bootstrap.php on line 77
Script php oil r install handling the post-install-cmd event returned with error code 255

Looks like a php 7.1 problem?
Guess this code is getting a little dated for that?