diff --git a/TODO.org b/TODO.org
index a192e5df..10285f11 100644
--- a/TODO.org
+++ b/TODO.org
@@ -644,10 +644,11 @@ awaiting confirmation, and the build order. Rules out Parinfer, wisp and
 sweet-expressions, and a simplified in-paren syntax — all thin the parens
 without removing them.
 
-** WAIT A lambda with a block cannot be a call's argument
-On the author's decision. =sort-by(xs, fn(a, b)= plus a block is refused; the
-lambda has to be bound first with =let=. Proposal: a call ending in =fn(...)= and a trailing =:=
-hands the block to that lambda: =sort-by(xs, fn(a, b)):=.
+** NEXT Lambdas are written with =>
+Decided 2026-09-26: a lambda's body follows ~=>~, and ~=>~ is its only spelling
+(~fn(a) = x~ is refused for a lambda; named functions keep ~=~). A header ending in ~=>~
+takes an indented block even inside brackets, closing where the brackets close:
+~sort-by(xs, fn(a, b) =>~ plus a block.
 
 ** NEXT A condition struct with a parent has no sugar
 On the author's decision. =defstruct(DiskFull, :parent, IoError, [free i64])= is the fallback, with a