The home of Afghan tech start-up Buber may boast more security precautions than the average California internet firm, but the Silicon Valley zeal of its staff is just the same.

Buber’s office features blast walls and armed guards rather than a relaxed campus of scooter-riding developers, yet they share the same West Coast belief in technology changing life for the better.

At its headquarters in the shadow of Kabul’s Darulaman palace, Buber hopes to become Afghanistan’s equivalent of the international ride-hailing giant Uber.

Undeterred by sliding security and regular attacks in the country, the firm believes it can master the power of smartphones to give Kabul residents safe, cheap taxi rides….