diff --git a/README b/README
deleted file mode 100644
index e1e61a2c4ec948625d648435feebbe2fd7612463..0000000000000000000000000000000000000000
--- a/README
+++ /dev/null
@@ -1,20 +0,0 @@
-PREREQUISITES
--------------
-
-This version is known to compile with:
-
- - Coq 8.5
- - Ssreflect 1.6
-
-For development, better make sure you have a version of Ssreflect that includes
-commit be724937 (no such version has been released so far, you will have to
-fetch the development branch yourself). Iris compiles fine even without this
-patch, but proof bullets will only be in 'strict' (enforcing) mode with the
-fixed version of Ssreflect.
- 
-BUILDING INSTRUCTIONS
----------------------
-
-Run the following command to build the full development:
-
-  make
diff --git a/README.md b/README.md
new file mode 100644
index 0000000000000000000000000000000000000000..41e3afbef0234f3cdf07158bee3150a1adfc9e07
--- /dev/null
+++ b/README.md
@@ -0,0 +1,33 @@
+# PREREQUISITES
+
+This version is known to compile with:
+
+ - Coq 8.5
+ - Ssreflect 1.6
+
+For development, better make sure you have a version of Ssreflect that includes
+commit be724937 (no such version has been released so far, you will have to
+fetch the development branch yourself). Iris compiles fine even without this
+patch, but proof bullets will only be in 'strict' (enforcing) mode with the
+fixed version of Ssreflect.
+ 
+# BUILDING INSTRUCTIONS
+
+Run the following command to build the full development:
+
+  make
+
+
+# STRUCTURE
+
+* The folder `prelude` contains an extended "Standard Library" by Robbert
+  Krebbers <http://robbertkrebbers.nl/thesis.html>.
+* The folder `algebra` contains the COFE and CMRA constructions as well as
+  the solver for recursive domain equations.
+* The folder `program_logic` builds the semantic domain of Iris, defines and
+  verifies primitive view shifts and weakest preconditions, and builds some
+  language-independent derived constructions (e.g., STSs).
+* The folder `heap_lang` defines the ML-like concurrent heap language, and a
+  few derived constructions (e.g., parallel composition).
+* The folder `barrier` contains the implementation and proof of the barrier.
+* The folder `examples` contains the examples given in the paper.
diff --git a/program_logic/weakestpre.v b/program_logic/weakestpre.v
index 023a801aaa6058ea1a20e173000bcbabd2e53fff..85fc236c54485e7bde79d8c90991fdfa592b2c9b 100644
--- a/program_logic/weakestpre.v
+++ b/program_logic/weakestpre.v
@@ -248,7 +248,7 @@ Proof. by setoid_rewrite (always_and_sep_r _ _); rewrite wp_frame_r. Qed.
 Lemma wp_impl_l E e Φ Ψ :
   ((□ ∀ v, Φ v → Ψ v) ∧ WP e @ E {{ Φ }}) ⊢ WP e @ E {{ Ψ }}.
 Proof.
-  rewrite wp_always_l; apply wp_mono=> // v.
+  rewrite wp_always_l. apply wp_mono=> // v.
   by rewrite always_elim (forall_elim v) impl_elim_l.
 Qed.
 Lemma wp_impl_r E e Φ Ψ :