diff --git a/README.md b/README.md
index b749ba1..969ce2d 100644
--- a/README.md
+++ b/README.md
@@ -1,16 +1,49 @@
-dependent
+trivial
 ===
 
-Typed Racket does not have dependent types, but [macros](http://www.greghendershott.com/fear-of-macros/) are a pretty close substitute.
-This library implements a few standard library functions as macros to provide strong compile-time guarantees.
-
-For example, `printf!` is a type-safe printer:
+This library provides ``smarter'' versions of Typed Racket standard library functions.
+For example:
 
 ```
-(require dependent/format)
-(printf! "hello, ~a\n") ;; Arity mismatch: expected 1 argument, got nothing.
+#lang typed/racket/base
+
+(require trivial)
+
+(printf: "hello, ~a")
+
+;; Compiling yields...
+;;
+;; format:: arity mismatch;
+;;  the expected number of arguments does not match the given number
+;;    expected: 1
+;;      given: 0
 ```
 
+The `printf:` (with a colon) checks whether its first argument is a string literal.
+If so, it parses the string's format sequences for arity and type constraints.
+Unless the constraints fail, `printf:` then calls the standard `printf`.
+
+When the first argument to `printf:` is not a string literal, nothing special happens; we just call the standard `printf`.
+
+```
+#lang typed/racket/base
+
+(require trivial)
+
+(let ([s "hello, ~a\n"])
+  (printf: s)) ;; Non-trivial!
+
+;; Compiles successfully, but throws arity error at runtime
+```
+
+Besides `printf:`, this library also provides [macros](http://www.greghendershott.com/fear-of-macros/)
+for:
+
+- `regexp-match`, to count the number of groups in a pattern and give the match result a more specific type
+- `+`, `-`, `*`, `/`, to reduce constants where possible, yielding results with more specific types.
+
+See the [documentation](http://pkg-build.racket-lang.org/doc/trivial/index.html) for the full story.
+
 
 Install
 ---
@@ -18,34 +51,32 @@ Install
 From Github:
 
 ```
-> git clone https://github.com/bennn/dependent
-> raco pkg install ./dependent
+> git clone https://github.com/bennn/trivial
+> raco pkg install ./trivial
 ```
 
 From the Racket [package server](http://pkgs.racket-lang.org/):
 
 ```
-> raco pkg install dependent
+> raco pkg install trivial
 ```
 
-Use `(require dependent)` to import all bindings from this library.
-Each file can be required individually, as in `(require dependent/format)`.
+Use `(require trivial)` to import all bindings from this library.
+Each file in the root directory of this repo can be imported specifically, as in:
+- `(require trivial/format)`
+- `(require trivial/regexp)`
+- `(require trivial/math)`
+
+These files only export macros.
 
 
-API
+Contributing
 ---
 
-Note: these are __macros__, not functions.
-Don't use them in higher-order positions.
+The perfect feature request would start like:
 
-Everything macro here is a front-end for a standard library function.
-Check the [Racket docs](http://docs.racket-lang.org/) for basic type signatures & behavior.
-This library's [Scribble docs](TODO) give full details on the static checks.
+    "Typed Racket rejects this program, but it is obviously well-typed because ..."
 
-#### `dependent/format`
-- `format`
-- `printf`
+If the right type really is obvious, syntactically, we'll extend this library.
 
-#### `dependent/regexp`
-- `regexp-match`