Build error - dependency problem while deploying to Heroku

System Information
  • Strapi Version: 3.4.5
  • Operating System: windows 10
  • Database:
  • Node Version: 14.15.4
  • NPM Version: 6.14.10
  • Yarn Version:

I’m trying to deploy an existing project to Heroku( using postgres). I follow all the instructions from the docs
but a have problems with dependencies. The original error is

npm ERR! While resolving: papageorgiou-website-strapi@0.1.0
       npm ERR! Found: pg@8.5.1
       npm ERR! node_modules/pg
       npm ERR!   pg@"^8.5.1" from the root project
       npm ERR! 
       npm ERR! Could not resolve dependency:
       npm ERR! peerOptional pg@"^7.18.2" from knex@0.20.15
       npm ERR! node_modules/knex
       npm ERR!   knex@"^0.20.15" from the root project
       npm ERR! 
       npm ERR! Fix the upstream dependency conflict, or retry
       npm ERR! this command with --force, or --legacy-peer-deps
       npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
       npm ERR! 
       npm ERR! See /tmp/npmcache.JAbfj/eresolve-report.txt for a full report.
       

I installed knex > 0.20.0 but I have other dependency problems then.

       npm ERR! Found: knex@0.21.17
       npm ERR! node_modules/knex
       npm ERR!   knex@"^0.21.17" from the root project
       npm ERR! 
       npm ERR! Could not resolve dependency:
       npm ERR! peer knex@"^0.20.0" from strapi-connector-bookshelf@3.4.5
       npm ERR! node_modules/strapi-connector-bookshelf
       npm ERR!   strapi-connector-bookshelf@"3.4.5" from the root project
       npm ERR! 
       npm ERR! Fix the upstream dependency conflict, or retry
       npm ERR! this command with --force, or --legacy-peer-deps
       npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
       npm ERR! 
       npm ERR! See /tmp/npmcache.HQE6r/eresolve-report.txt for a full report.
       
       npm ERR! A complete log of this run can be found in:
       npm ERR!     /tmp/npmcache.HQE6r/_logs/2021-02-04T06_33_28_188Z-debug.log
-----> Build failed

Any suggestions?

Solve it by checking here:
https://github.com/strapi/strapi/issues/8786

For some reason I couldn’t find this link yesterday,
I followed this instructions as posted by the last user → changing npm from >=6.0.0 to 6.14.9