Open Source

  • I released concurrency-1.8.1.0, adding a newTVarConc method to MonadConc:

    -- | Create a @TVar@. This may be implemented differently for speed.
    --
    -- > newTVarConc = atomically . newTVar
    --
    -- @since 1.8.1.0
    newTVarConc :: a -> m (TVar (STM m) a)
    newTVarConc = atomically . newTVar
    

    The IO instances uses newTVarIO.

Work

  • This week had a bunch of little things:

  • I was off on Thursday to go look at some flats in Rickmansworth. More on that later.

Miscellaneous

  • I read The Path of Daggers (by Robert Jordan), the eighth book in the Wheel of Time series.

  • I continued with my project to get GOV.UK running on Kubernetes, and have made some good progress this week:

    I’ve got some really neat stuff set up, for example:

    • An app which requests storage will automatically provision and attach an EBS volume
    • An app which accepts external traffic will automatically provision an ALB and set up a Route53 entry

    I’ve started to work on the publishing apps, but I’ve not done much more than deploy content-store and a proof-of-concept MongoDB instance. I’d like to also deploy search-api, router-api, and router (with their respective databases); putting in some fake data; and seeing if it all works. Once that proof-of-concept has been tested, I’d then like to switch to using the AWS managed Elasticsearch and Document DB, rather than running them myself.

  • In the process of switching govuk-k8s to using EKS, I also switched it from nginx to Caddy, because it turns out nginx has some really strange ideas about hostnames:

    This also switches from nginx to caddy because nginx has some interesting ideas about hostnames:

    1. If given statically, nginx resolves all hostnames at start-up.

      • If a hostname doesn’t resolve, nginx doesn’t start. This is a problem because the ALBs won’t exist until the apps are deployed.

      • If a hostname is changed to point to a different IP, nginx won’t pick up that change either.

    2. If given dynamically (in a variable), nginx forces you to construct the proxy URL yourself.

      • It seems exceedingly difficult to construct a URL based on user-supplied input which doesn’t open a possibility of SSRF.

    Caddy solves both of these problems by just behaving sensibly with hostnames.

    I’ve known about Caddy for a while, but not tried it before. The configuration is way simpler than nginx, as it has more sensible defaults. I’m planning to switch all my servers from nginx to Caddy now.

  • I went to see three flats in Rickmansworth on Thursday, and decided to rent one of them. It’s a five minute walk from the tube station, which itself is about an hour away from the station next to work. My criteria when looking for a flat were:

    • No more than an hour and a half from work
    • The commute to work is a single tube journey / bus ride / whatever
    • Can get at least 300Mb internet (preferably Hyperoptic, but that proved far too limiting)
    • Has space for: VR gaming, table-top gaming, and a computer desk

    My current flat is pretty small, and I’ve had to move my computer every time I wanted to use the table for boardgames, which sucks a lot. The flat I picked is over twice the size, and has a second bedroom which I can turn into a home office.