diff --git a/CONVENTIONS.md b/CONVENTIONS.md
index 1b04ee6b8..e69c3cdd7 100644
--- a/CONVENTIONS.md
+++ b/CONVENTIONS.md
@@ -5,10 +5,64 @@
 
 - [Spacemacs conventions](#spacemacs-conventions)
     - [Code guidelines](#code-guidelines)
+        - [Spacemacs core and layer](#spacemacs-core-and-layer)
+        - [All layers](#all-layers)
     - [Key bindings conventions](#key-bindings-conventions)
+        - [Prefix reserved to the user](#prefix-reserved-to-the-user)
+        - [Navigation in `insert state` buffers](#navigation-in-insert-state-buffers)
+        - [Interactions with REPLs](#interactions-with-repls)
 
 <!-- markdown-toc end -->
 
 ## Code guidelines
 
+### Spacemacs core and layer
+
+Function names follow these conventions:
+- `spacemacs/xxx` is an interactive function called `xxx`
+- `spacemacs//xxx` is a private function called `xxx` (implementation details)
+- `spacemacs|xxx` is a _macro_ called `xxx`
+
+Variables follow these conventions:
+- `spacemacs-xxx` is a variable
+- `spacemacs--xxx` is a private variable (implementation details)
+
+### All layers
+
+A package is initialized in a function with name `<layer>/init-xxx` where:
+- `<layer>` is the layer name
+- `xxx` is the package name
+
 ## Key bindings conventions
+
+### Prefix reserved to the user
+
+`<SPC> o` must not be used by any layer. It is reserved for the user.
+
+### Navigation in `insert state` buffers
+
+Navigation in buffers like `Helm` and `ido` which are in `insert state` should
+be performed with <kbd>C-j</kbd> and <kdb>C-k</kbd> for vertical movements.
+
+History navigation in shells or REPLs buffers should be bound as well to
+<kbd>C-j</kbd> and <kdb>C-k</kbd>.
+
+### Interactions with REPLs
+
+A lot of languages can interact with a REPL. To help keeping a consistent
+behavior between those languages the following conventions should be
+followed:
+- lower case key bindings keep the focus on the current buffer
+- upper case key bindings move the focus to the REPL buffer
+
+    Key           |                 Description
+------------------|------------------------------------------------------------
+<kbd>b</kbd>      | evaluate buffer
+<kbd>B</kbd>      | evaluate buffer and switch to REPL
+<kbd>f</kbd>      | evaluate function
+<kbd>F</kbd>      | evaluate function and switch to REPL
+<kbd>l</kbd>      | evaluate line
+<kbd>L</kbd>      | evaluate line and switch to REPL
+<kbd>r</kbd>      | evaluate region
+<kbd>R</kbd>      | evaluate region and switch to REPL
+