Cannot find module './db.json'

[loudbirds]

yarn prod:start v1.24.5
$ cross-env NODE_ENV=production pm2 start lib/server && pm2 logs
[PM2] Applying action restartProcessId on app [server](ids: 0)
[PM2] server ✓
[PM2] Process successfully started
┌──────────┬────┬──────┬───────┬────────┬─────────┬────────┬─────┬───────────┬──────────┐
│ App name │ id │ mode │ pid │ status │ restart │ uptime │ cpu │ mem │ watching │
├──────────┼────┼──────┼───────┼────────┼─────────┼────────┼─────┼───────────┼──────────┤
│ server │ 0 │ fork │ 53589 │ online │ 105 │ 0s │ 0% │ 11.9 MB │ disabled │
└──────────┴────┴──────┴───────┴────────┴─────────┴────────┴─────┴───────────┴──────────┘
Use pm2 show <id|name> to get more details about an app
[TAILING] Tailing last 15 lines for [all] processes (change the value with --lines option)
/Users/ervinbosenbacher/.pm2/pm2.log last 15 lines:
PM2 | 2017-06-08 11:24:55: Starting execution sequence in -fork mode- for app name:server id:0
PM2 | 2017-06-08 11:24:55: App name:server id:0 online
PM2 | 2017-06-08 11:24:55: App [server] with id [0] and pid [53508], exited with code [1] via signal [SIGINT]
PM2 | 2017-06-08 11:24:55: Starting execution sequence in -fork mode- for app name:server id:0
PM2 | 2017-06-08 11:24:55: App name:server id:0 online
PM2 | 2017-06-08 11:24:55: App [server] with id [0] and pid [53511], exited with code [1] via signal [SIGINT]
PM2 | 2017-06-08 11:24:55: Script /Users/ervinbosenbacher/dev/gridsearch/frontend/lib/server had too many unstable restarts (16). Stopped. "errored"
PM2 | 2017-06-08 11:27:24: Starting execution sequence in -fork mode- for app name:server id:0
PM2 | 2017-06-08 11:27:24: App name:server id:0 online
PM2 | 2017-06-08 11:27:24: App [server] with id [0] and pid [53589], exited with code [1] via signal [SIGINT]
PM2 | 2017-06-08 11:27:24: Starting execution sequence in -fork mode- for app name:server id:0
PM2 | 2017-06-08 11:27:24: App name:server id:0 online
PM2 | 2017-06-08 11:27:24: App [server] with id [0] and pid [53594], exited with code [1] via signal [SIGINT]
PM2 | 2017-06-08 11:27:24: Starting execution sequence in -fork mode- for app name:server id:0
PM2 | 2017-06-08 11:27:24: App name:server id:0 online

/Users/ervinbosenbacher/.pm2/logs/server-out-0.log last 15 lines:
0|server | Server running on port 8000 (production).
0|server | Server running on port 8000 (production).
0|server | Server running on port 8000 (production).
0|server | Server running on port 8000 (production).
0|server | Server running on port 8000 (production).
0|server | Server running on port 8000 (production).

/Users/ervinbosenbacher/.pm2/logs/server-error-0.log last 15 lines:
0|server | at Object.Module._extensions..js (module.js:579:10)
0|server | at Module.load (module.js:487:32)
0|server | at tryModuleLoad (module.js:446:12)
0|server | at Function.Module._load (module.js:438:3)
0|server | Error: Cannot find module './db.json'
0|server | at Function.Module._resolveFilename (module.js:469:15)
0|server | at Function.Module._load (module.js:417:25)
0|server | at Module.require (module.js:497:17)
0|server | at require (internal/module.js:20:19)
0|server | at Object. (/Users/ervinbosenbacher/dev/gridsearch/frontend/lib/node_modules/mime-types/node_modules/mime-db/index.js:13:18)
0|server | at Module._compile (module.js:570:32)
0|server | at Object.Module._extensions..js (module.js:579:10)
0|server | at Module.load (module.js:487:32)
0|server | at tryModuleLoad (module.js:446:12)
0|server | at Function.Module._load (module.js:438:3)

[STREAMING] Now streaming realtime logs for [all] processes
0|server | Error: Cannot find module './db.json'
0|server | at Function.Module._resolveFilename (module.js:469:15)
0|server | at Function.Module._load (module.js:417:25)
0|server | at Module.require (module.js:497:17)
0|server | at require (internal/module.js:20:19)
0|server | at Object. (/Users/ervinbosenbacher/dev/gridsearch/frontend/lib/node_modules/mime-types/node_modules/mime-db/index.js:13:18)
0|server | at Module._compile (module.js:570:32)
0|server | at Object.Module._extensions..js (module.js:579:10)
0|server | at Module.load (module.js:487:32)
0|server | at tryModuleLoad (module.js:446:12)
0|server | at Function.Module._load (module.js:438:3)
PM2 | App [server] with id [0] and pid [53598], exited with code [1] via signal [SIGINT]
PM2 | Starting execution sequence in -fork mode- for app name:server id:0
PM2 | App name:server id:0 online
0|server | Error: Cannot find module './db.json'
0|server | at Function.Module._resolveFilename (module.js:469:15)
0|server | at Function.Module._load (module.js:417:25)
0|server | at Module.require (module.js:497:17)
0|server | at require (internal/module.js:20:19)
0|server | at Object. (/Users/ervinbosenbacher/dev/gridsearch/frontend/lib/node_modules/mime-types/node_modules/mime-db/index.js:13:18)
0|server | at Module._compile (module.js:570:32)
0|server | at Object.Module._extensions..js (module.js:579:10)
0|server | at Module.load (module.js:487:32)
0|server | at tryModuleLoad (module.js:446:12)
0|server | at Function.Module._load (module.js:438:3)
PM2 | App [server] with id [0] and pid [53601], exited with code [1] via signal [SIGINT]
PM2 | Starting execution sequence in -fork mode- for app name:server id:0
PM2 | App name:server id:0 online
0|server | Error: Cannot find module './db.json'
0|server | at Function.Module._resolveFilename (module.js:469:15)
0|server | at Function.Module._load (module.js:417:25)
0|server | at Module.require (module.js:497:17)
0|server | at require (internal/module.js:20:19)
0|server | at Object. (/Users/ervinbosenbacher/dev/gridsearch/frontend/lib/node_modules/mime-types/node_modules/mime-db/index.js:13:18)
0|server | at Module._compile (module.js:570:32)
0|server | at Object.Module._extensions..js (module.js:579:10)
0|server | at Module.load (module.js:487:32)
0|server | at tryModuleLoad (module.js:446:12)
0|server | at Function.Module._load (module.js:438:3)
PM2 | App [server] with id [0] and pid [53604], exited with code [1] via signal [SIGINT]
PM2 | Starting execution sequence in -fork mode- for app name:server id:0
PM2 | App name:server id:0 online
....

I have the above output when I am running prod:start after prod:build.

I have tried to npm install the packages into a separate directory and then copy it which partially solved the problem as then I had other Cannot find module errors as well. The last one was flatten-array from express

I am fairly new to Javascript, is this a bug due to some latest packages?
Any help would be much appreciated.

Regards