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+**Matzo** is my first attempt at a language designed for creating random text fragments, now reimplemented in Rust.
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+
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+(The earlier versions were Haskell and JavaScript, and both have bit-rotted rather badly: I'm hoping that this version is both cleaner—on account of my writing it a decade later—and also that this version is easier to modify and will be more resilient to bit-rot.)
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+
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+## Matzo basics
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+
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+There are two basic kinds of statements: assignment and printing. Assignment is usually done with `:=`. All statements are terminated with a semicolon (although the REPL will usually tolerate you leaving it off.)
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+
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+```
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+greeting := "hello";
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+```
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+
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+Printing statements are written with `puts`.
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+
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+```
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+puts greeting; (* prints "hello" *)
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+```
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+
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+The two most common operations are catenation and choice. Catenation is indicated by simply putting expressions next to each other:
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+
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+```
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+puts "Hello" " " "world!";
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+```
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+
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+Choice is indicated by putting vertical bars between various choices.
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+
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+```
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+puts "Hello!" | "Hey!" | "Yo!";
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+```
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+
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+Catenation binds more tightly than choice, but parentheses can explicitly group operations.
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+
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+```
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+puts ("Bonjour" | "Buenos dias") ", world!";
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+```
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+
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+Choices can also be weighted by using a number and `:`. In the following example, there's a 1/6 chance of getting `"tails"`, and a 5/6 chance of getting `"heads"`:
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+
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+```
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+puts 5: "heads" | "tails";
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+```
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+
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+Since it's quite common to want to choose from some basic string literals, there's a special case for that: the `::=` operator allows you to list zero or more space-separated identifiers, and then it will treat them as strings and choose between them with equal weight.
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+
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+```
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+suits ::= hearts diamonds clubs spades;
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+(* this is equivalent to writing
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+ suits := "hearts" | "diamonds" | "clubs" | "spades";
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+*)
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+```
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+
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+Importantly, definitions in Matzo are _lazy_: if something is defined as a choice between alternatives, then every use of that thing has a chance of choosing a different alternative.
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+
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+```
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+letter ::= a b;
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+(* this might print any of aa, ab, ba, bb *)
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+puts letter letter;
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+```
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+
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+Matzo also allows you to _fix_ definitions, which will evaluate them once and use that version for every subsequent reference. There are two ways of doing this: one is to prefix the assignment with the `fix` keyword:
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+
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+```
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+fix letter ::= a b;
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+(* this can only print aa or bb *)
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+puts letter letter;
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+```
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+
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+The other is to use `fix` as a standalone statement, which modifies a definition in-scope by fixing it.
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+
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+```
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+letter ::= a b;
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+puts letter letter; (* aa, ab, ba, or bb *)
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+fix letter;
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+puts letter letter; (* aa or bb *)
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+```
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+
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+## Fancier Matzo
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+
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+- Data types (atoms, tuples)
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+- Functions
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+- Pattern-matching
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+
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+## Implementation notes
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+
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+## Todo
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+
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+- [ ] Pattern matching
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+- [ ] Closures
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+- [ ] Expand the stdlib
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+- [ ] Switch to packed expr representation for easier sharing
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+- [ ] Think about how to express GC
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Getty Ritter