His contributions to software development were many. One thing this cat worked out that no Apple/Microsoft/Ubuntu software engineer managed to notice was that repeatedly holding down the 'Print Screen' button would permanently immobilise a computer, making a reboot required. Try it for yourself - the multitude of dialog boxes builds up and makes the computer not usable. This is also the case if the computer is locked, on Ubuntu (and maybe Windows) the dialog box still pops up on pressing 'Print Screen' at the login prompt.
I would say that the H.R. department also liked the cat as on any tour given to a new employee the introductions would be made. At least one of my colleagues joined the company because they liked the cat friendly working environment. So he was definitely a hit for recruitment and retaining employees.
There certainly was no rodent problem but I was on the side of the mice and have prised his jaws open on a few occasions to let some terrified creature escape to die from shock a short while later.
To get to the office this cat would take a stroll through an artist's studio. One time he arrived covered in pink, orange and grey paint. He had ruined a painting that was due to be sent to a posh gallery in New York. As it turned out a lot of people wanted to buy that particular painting as it had been 'improved' by the cat, so it sold for an absolute fortune, unlike the rest of the collection. The paint lasted quite a long time on him as it was oil based. This was one of many legendary stories concerning this hard working cat, he also stowed away on a boat and went missing for a fortnight, eventually making his way back home all by himself.
His actual owners had a fireplace showroom as part of their building business, so this cat chose our office over his own 'workplace' where he had a dozen or so fireplaces to sprawl out in front of. Needless to say he did a good job of selling the fireplace lifestyle to people too.
I think there were a good half dozen or so elderly ladies that he would check up on so another of his roles was as a care worker. Without his visits they would have not had as much exercise and contact with 'people', they would let him in but shun human 'care workers' so he did take his care work seriously.
This cat did have actual staff, so the handyman would go to a posh supermarket to buy fresh king size Icelandic prawns for him on a daily basis. If the prawns were a day old then he would turn his nose up and dine out on mice.
As for his hunting skills, his agility was a mix of Houdini and those oriental style martial art films. His breaking and entering skills were tantamount to magic. He could also move mid-air in a way that defied physics, making 90 degree turns mid-leap. He defended his territory and as well as keeping the vermin down he would teach dogs who was boss. Once he broke up a fight between two dogs giving both of them bloody noses, intervening where no human dared.
He also made timely entrances in company meetings, once when the boss was called to the front this cat decided that he should spring forward and beat him to the stage. This had everyone in hysterics.
In North London there is a special cemetary for working animals, I would like to go there some time. There are ship's cats from previous wars, pigeons from WW1, servicemen's dogs and other remarkable working 'animals' buried there. Recently they renovated the place and had a 'fly by' of pigeons which I would like to have seen. I think my feline friend has contributed enough to be worthy of a place there when the time comes in eight lives' time...