(Note: I may ramble a bit. And: this is mostly about programming.)
The genesis of MarsEdit was the idea of mitosis, that we could remove
NetNewsWires weblog editor and create a new, separate weblog
editorand thereby create a better newsreader and a better weblog editor.
We had long planned to support external weblog editors in
NetNewsWirebut it wasnt until autumn 2003 that we considered
supporting only external weblog editors. Thats when we first sketched out MarsEdits user interface.
To my delight, the final version of MarsEdit looks very, very much like
our original vision, done originally as a non-functioning prototype in
Splitting up NetNewsWire like this was a big risk, though, and we
didnt know how it would be received. (It turned out that the feedback
far surpassed our hopes.)
We not only split up the product but created an open interface
so that various combinations of newsreader and weblog editor could work
together. This is something were very proud ofeven though it
increased the risk.
Early on, before testers even saw it, I had a few challenges…
1. Morphing user interface
I had to develop an
adaptable user interface that morphs based on the capabilities of
different weblog systemsand not have the morphing be obnoxious.
This was a response to one of the major problems with NetNewsWires
weblog editor: fields that a given system couldnt use were just
disabled rather than disappeared. This led to lots of email and bug
reports. Though Im not generally a fan of UIs that morph, it had to be
done hereand I was utterly pleased with the result.
At first, actually, I was entrancedI used to just keep changing the
weblog system to watch the animation of fields appearing and
disappearing. But I got over it and went to work on the next thing.
2. Asynchronous XML-RPC
I had to do a better job dealing with asynchronous XML-RPC calls than I did in NetNewsWire.
the dealyou click a button like Post or Refresh, it kicks off a call
to the server to do something. MarsEdit waits for the responsebut it
cant lock up while waiting, it has to be responsive to your commands,
and it has to do things like run a progress indicator. And calls have
to be chainable: make a second call after the first completes, but not
Well, I had this working in NetNewsWires old weblog editor, but I was
never pleased with it, and there were times when the UI would miss the
response, and a progress indicator would run forever.
This was just an architecture job. I ended up with a system both
cleaner and better than what was in NetNewsWire. (The second time is
usually better than the first, after all.)
What I ended up with was solid plumbing. With leaky plumbing, you spend
all your time patching it and not enough time working on the UIand the
UI is where you need to spend your time.
I have barely touched this code (except to add a minor feature or two)
since MarsEdit first went into private testing, which says alot for the
From a high level, every net operation looks like an Objective-C method
call that, instead of returning a value, returns immediately and calls
back to a method when its done. Since the code is object-oriented,
maintaining state is almost not even an issue. (Simple stuff, nothing
revolutionary, just plain old-fashioned goodness.)
Cocoa has wonderful built-in support for document-based applications.
The only trouble is, that support assumes that youre saving documents to disk.
whole point of MarsEdit was to be document-centered, like emailbut,
also like email, you dont save files to disk, you send your document
to the internet somewhere.
I had to learn about Cocoas document-based app featuresand, at the
same time, I had to learn how and where to over-ride it so that it
didnt think it was loading and saving disk-based documents. This
turned out to be difficultlots of trial-and-error. The docs dont talk
about this much.
And the early, private testers would tell you that I didnt have all the kinks worked out in the first versions they saw.
Design philosophy: maximum elegance
Throughout the process of working on MarsEdit, the phrase maximum
elegance repeated in my head. The idea was to keep it as simple and
focused as possible.
As Ive written before, weblog editing is far more complex than email:
you have things like categories and text filters and trackbacks and all
this stuff you dont have with email.
The phrase maximum elegance was just a personal reminder to myself to
simplify as much as possible. With something as complicated as weblog
editing, you have to be relentless about simplification, or it will get
away from you.
Note, for instance, how short and small MarsEdits menu is. How many
other productivity apps do you use have such a small menu? Note how the
design of document windows is influenced by Apple Mail rather than,
say, Microsoft Word.
The lightness of an application is a matter of feel rather than
number of lines of code or number of resources. Its a design issue. I
wanted MarsEdit to feel weightless in order to balance the heavy complexity of weblog editing.
Note to developersregular folks, please skip thisthere is, oddly, a
danger to making an app feel light. People sometimes get the impression
that its not light but slightthat
it cant possibly have very many features and couldnt have taken much
time to develop, so it cant possibly be worth paying money for. Thats
not true, of course. (Its like that old line about not having enough
time to write a short letter.) However, even though theres this
danger, its better to go for lightness, because the vast majority of
Mac users appreciate quality.
The early, private testers were a huge help with this. I simplifiedbut
they simplified even more. There was lots of feedback about stuff that
could be removed from these early versions, and I think I used all of
it. (Im a strong proponent of development-by-subtractionafter all,
MarsEdit exists because we removed the weblog editor from NetNewsWire.)
Of course, theres no design nirvana. MarsEdit is very close to my
original vision, and thats wonderfulas long as the original vision is
good. But is there room for improvement? Could the user interface be
better still? Yes, of course. (And I already have plenty of ideas for
how to make it better.)
Once MarsEdit was in public beta, it was fairly close to what 1.0 would become, but of course there were bugs to fix.
And it turned out that there were a couple features I was putting off until after 1.0 that really needed to be in 1.0:
1. Preview with text filtersMarkdown and similar.
2. Customizable list of URLs to ping.
not to say there werent plenty of other feature requests, but so many
people asked for these two that it became apparent that they had to be
in 1.0. If I could have waited on these, I would have.
Before deciding to implement them, I had to answer a few questions for each feature:
1. How much time would it take to develop?
2. How much time would it take to test?
3. Is this feature a likely site of bugs, or will it be straightforward?
4. Can it fit in the existing user interface without major disruption?
For text-filter-preview and customizable pings list, I guessed (and all
you can do is make an educated guess) that they would be quick to
develop and test, that theyre straightforward, and that the user
interface wouldnt require many changes.
Another popular feature request was supporting titles for Blogger. This
we didnt do in 1.0, because it would take too long to develop and test
and it would be a likely site of bugs. It sounds crazywere just
talking about titles, no big thing, right?but it required adopting the
Atom editing API, which is a big job. (Now that 1.0 has shipped, this
is MarsEdits top priority, by the way.)
There werent many features pursued that I had to drop or change drastically. Just a few things:
At one point during the private beta I wanted to add what I thought was
a cool Rendezvous-based featurebut it didnt interest the testers, and
finally it didnt interest me personally that much, and I dropped it
before spending programming time on it.
2. The first versions of MarsEdit did previews quite a bit differently:
the preview appeared in a drawer attached to the document window. This
was cool for one major reason: it tied the editing window and the
preview together. In a way, this is much better than having a separate,
single preview window. But it had a serious drawback: you couldnt
resize the preview independently of the size of the editing window.
At one point I considered doing the preview as a splitview in the
document window, which would have let you semi-independently resize
itbut I ended up going for a separate preview window. (There were
testers on all sides of this issue, by the way: there was no consensus.
Sometimes a solution is obvious to everyone but the developer, but not
3. For a long time during the beta process the app icon looked very
much like the Firefox icon. (This was just coincidencethe MarsEdit
icon was originally created before the Firefox icon was created. The
final icon Bryan Bell created is fantastic. I love it.)
The real story behind the name MarsEdit
In an alternate universe, MarsEdit is an outliner instead of a weblog
editorand its name is MarsLiner. It has the exact same icon MarsEdit
When I first asked Bryan to make a Mars-with-spaceship iconway back in
early 2003 (I thinkcould have been 2002) it was for an application
named MarsLiner. The idea was to do an outliner that could fill in for MORE.
Its been a sore spot in my computing life that no outliner for OS X
feels as good to me as MORE did. This is purely subjective, of
coursethere are several really great outliners for OS X. But I want
MORE, and I was willing to write it myself. (Just the outliner, that
isI didnt care about the presentation stuff in MORE.)
The idea was to have a text-oriented outlinerI didnt care about
embedding movies and sound clips and whatnotthat was designed for
keyboard users, felt very light, and was super-fast.
The rough draft of this idea was the Notepad in NetNewsWire 1.x. But
MarsLiner was to be a huge improvement, it was supposed to be the
outliner of my dreams.
But then I discovered something important: most people dont care about
outliners. And the people who do care about outliners, many of them
would want the embedded media features that I didnt care about. So I
realized that the market would be small, just a subset of the outliner
market, which is small enough alreadyand there are already some great
When we decided to bag MarsLiner and do a separate weblog editor
instead, I wanted to use the name Mars somehow and use Bryans cool
icon. Hence the name MarsEdit. We rationalized the name by saying it
represents editing at a distance, since youre not editing local
documents, youre editing documents that live on the web somewhere.
But really it was because I like Mars and spaceships and we already had a great Mars icon.
How much programming time had I spent on MarsLiner? Very little,
thankfullyI built NetNewsWires Notepad as a stand-alone app. I didnt
even get as far as supporting multiple documents or doing a save
But still today I wish for the outliner of my dreams.
From time to time Im tempted to do it as a Terminal-based thing, all
done with ncurses. This way it would have to be purely keyboard-based;
it wouldnt be able to display pictures or movies; it would be fast.
Maybe you will do it. I can dream, right? [inessential.com]