Simple list of applicants webapp

I am creating a web application that lists applicants and their position on a waiting list.

We need to be able to add new applicants to this list and remove applicants from the list. There will be under 10k applicants in the list.

Specifics:

• I plan to write the app in Golang.

• The list needs to be safe, I the program shuts down, it should be recoverable.

• The app should contain this data for every applicant: Name, Student ID, position.

Questions:

1. How do I secure the list (lock?) so it is updated correctly for both if two updates to it is made at the same time?
2. Should I save the data in a database or use a file?

I need your help!

UPDATE:

Mockup code:

package main

import (
	"log"
	"sync"
	"time"

	"github.com/boltdb/bolt"
)

type applicant struct {
	FirstName string
	LastName  string
	StudentID string
	Position  int
}

type priorityList struct {
	sync.Mutex
	applicants []applicant
}

func (l *priorityList) newApplicant(fn string, ln string, sid string) error {

	// add applicant to priorityList
	return nil
}

func (l *priorityList) removeApplicant(sid string) error {
	// remove applicant from priorityList
	return nil
}

func (l *priorityList) editApplicant(sid string) error {
	// edit applicant in priorityList
	return nil
}

func main() {
	// Database
	db, err := bolt.Open("priorityList.db", 0600, &bolt.Options{Timeout: 1 * time.Second})
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()
}

If you use a file, you could use a Mutex to block concurrent writes.

Otherwise a database would be fine. For example BoltDB could be suitable. It is pure go and runs withing your program.

There are many approaches. You can use file and protect it with Go mutex or system lock. You can memory map the file for performance. You either can use BoltDB which is nice peace of software and provide needed machinery and can work in-process. If you write rare and mostly read, then constant DB https://github.com/colinmarc/cdb also looks interesting.
But, classic SQL DB has some advantages

• You can use third party store for data and easely migrate when needed
• You can access your data from third party app or just plain SQL
  request
• You can think about data schema and code logic separately