i'm using a web browser broadly similar to mosaic (01994) on a site that works similarly to early reddit (02005). in another window i'm running irssi (01999) to chat on irc (01988, but i've only been using it since 01994) inside screen (01987, but i've only been using it since 01994), to which i'm connected with ssh (01996) and mosh (02011, but i didn't start using it until last month). in my unix shell window (mate-terminal, but a thin wrapper around libvte (02002), mostly emulating a vt100 from 01978) i'm running a bourne shell (01979, but really it's brian fox's better reimplementation which he started in 01989) in which i just ran yt-dlp (which has to be updated every couple of months to keep working, but mostly has the same command-line flags as youtube-dl, first released in 02006) to download a video encoded in h.264 (02003) in an mpeg-4 container (01998), and then play it with mpv (02013, but forked from and sharing command-line flags with mplayer (02000)). mpv displays the video with a gpu renderer (new) on a display server running x11 (01987).

in another browser tab i'm running jupyter (the renamed ipython notebook from 02011) to graph some dsp calculations with matplotlib (02003, but mostly providing the plotting functions from matlab (01984)) which i made with python (01991, but i've only been using it since 02000) and numpy (02006, but a mostly compatible reimplementation of numeric from 01995, which i've been using since 02003). in jupyter i can format my equations in latex (01984, but for equations basically the same as plain tex82 from 01982, but i've only been using them since 01999) and my text in markdown (02004, though jupyter's implementation supports many extensions). i keep the jupyter notebook in git (02005, but i've only been using it since 02009, when i switched from cvs (01986, but i've only been using it since about 01998)). the dsp stuff is largely applications of the convolution theorem (01822 or 01912) and hogenauer filters (01981).

i do most of my programming that isn't in jupyter in gnu emacs (01984, but i didn't start using it until 01994) except that i prefer to do java stuff in intellij idea, which i first used in 02006

earlier this year, my wife and i wrote our wedding invitation rsvp site in html (01990, but using a lot of stuff added up to 02000) and css2 (01998) plus a few things like corner-radius (dunno, 02006?) and a little bit of js (01995, but in practical terms 02004), with the backend done in django (02005) backed by sqlite (02000, but this was sqlite3 (02004), but sqlite mostly just implements sql (01974, first publicly available in 01979, but mostly the 01992 ansi standard) which in turn mostly just implements codd's relational data model (01970) and acid transactions (01983), all of which i've been using since 01996). and of course python, emacs, and git. most of the css debugging was done with chromium's web inspector (present from the first chrome release in 02008, a clone of firebug (02006)).

for looking up these dates just now, i used google's newish structured search results, which mostly pull information from wikipedia (02001); i also used stack overflow (02008) and its related sites.

the median of the years above is 01998, with 25% and 75% quartiles of 01987 and 02004, which i calculated using r (01997, but a reimplementation of s (01976)). if we assume that each new introduction listed above displaced some existing skill, then we can vaguely handwave at a half-life of about 25 years for these churning technology skills, which to me seems like enough time for a lot of them to amortize; but it seems like it's slowing down a lot, because the 25% quartile is in 01987 and not 01973

it's true that all the time i spent configuring twm, olvwm, fvwm, and afterstep, and working around bugs in netscape 4's javascript implementation, and maintaining csh scripts and informix ace database applications, and logging into anonymous ftp sites running tops-20, and debugging irq conflicts, isn't really serving me today. but you could kind of tell that those things weren't the future. the surprising thing is really how slowly things change: that we're still running variants of the bourne shell in emulators of the vt100

other still-relevant technological skills for me today include building a fire, qwerty typing, ansi c (my wife is taking a class), bittorrent, operating a gas stove, and making instant coffee. still beyond me, though, is how to turn this tv on