Everything about a piece except the music itself can now be manipulated from the interface. Musicians, instruments, staves and layouts are assembled, numbered, renamed, cloned, reordered and deleted by gesture; a piece's settings live in a window of their own; a field refuses a value it cannot take, in the field you typed it into, in your own language. Each act is one transaction, one event, one named undo step, and the path is identical alone or with a collaborator on another machine. Preparing the Ground marks the moment a layout opened into its own window – empty, and meant to be; Layout Windows and What Owns Them and We Have a Piece Settings Window show the last of the work; ADR-0053 and ADR-0054 hold the design.

That sentence names a boundary ADR-0052 drew long before the summer: the things that contain the music announce their changes structurally; the music itself defers to a formatting pipeline that doesn't yet exist. One side of that line is complete to the interface.

The other half of the period doesn't show on screen. Nessun Dorma describes it: no part of Ooloi can fail silently, no mechanism can be switched off by a single error, nothing anywhere sleeps and checks, and a save that doesn't happen says why. What the summer found was written down as invariants rather than guidance, stated where a later change cannot quietly break them; and the pattern from the engine held at the application layer, narrow tickets widening into general mechanisms because correct foundations make the general case cheap. Since August 1: 998 commits, 53 tickets closed.

Three shorter posts. Time Doesn't Stop follows one consequence of an interface that never blocks: the Undo item can rewrite itself while you read it. For the Babel Fish Out There introduces the Translators' Guide, for native speakers who can tell Ooloi when it talks nonsense in one of its twenty languages. Cortisol Levels is about the tool I build this with, and about me.

What remains before the notes has one definition of done, and it's a confirmation of things already known to work rather than a test: two clients open the same piece, one changes the beam thickness in Piece Settings, the other sees the new value without doing anything. Real authentication, two machines. Then plugins, Skija, the rendering pipeline.

The Machinery of Taste is the one to read. It sets that sequence out and then says what actually changes, which is not the subject matter. For two years every argument could be settled by running something. Nothing in the next phase works that way: no test will say a beam slope is beautiful, and the only instrument left is a musician's eye.

– Peter Bengtson
ooloi.org