diff --git a/DESCRIPTION b/DESCRIPTION
index 115f04bf..e4da849c 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: blockr
 Title: A block-based framework for data manipulation and visualization
-Version: 0.0.2.9031
+Version: 0.0.3.9000
 Authors@R: 
     c(person(given = "Nicolas",
              family = "Bennett",
diff --git a/NEWS.md b/NEWS.md
index f6f2e77c..4bc95d5c 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,47 @@
+# blockr 0.0.3.9000
+
+## Breaking changes
+- `register_blocks()` and `register_block()` __input__, __output__ have been changed. If your package is composed of __data__ or __transform__ blocks, nothing has to be done, expect removing the old registration API. If you developed custom blocks, whose classes are neither __data__ or __transform__, you'll have to develop a type checker like so, for a plot block:
+
+```r
+block_input_check.plot_block <- function(x, data, ...) {
+
+  if (inherits(data, "data.frame")) {
+    return(invisible(NULL))
+  }
+
+  input_failure("Expecting data.frame input.")
+}
+
+block_output_ptype.plot_block <- function(x, ...) ggplot()
+```
+
+Besides, there is no need to specify the __classes__ as this is automatically retrieved from the constructed block.
+As a consequence, the new registration looks like:
+
+```r
+# NEW
+register_block(
+  constructor = new_ggplot_block,
+  name = "ggplot",
+  description = "Initialise a ggplot2 plot",
+  category = "Plot",
+  package = pkg
+)
+
+# OLD
+register_block(
+  constructor = new_ggplot_block,
+  name = "ggplot",
+  description = "Initialise a ggplot2 plot",
+  classes = c("ggplot_block", "plot_block"),
+  input = "plot",
+  output = "plot",
+  category = "Plot",
+  package = pkg
+)
+```
+
 # blockr 0.0.2.9031
 
 ## Feature
diff --git a/_pkgdown.yml b/_pkgdown.yml
index 978229fb..cac08513 100644
--- a/_pkgdown.yml
+++ b/_pkgdown.yml
@@ -144,6 +144,8 @@ reference:
   - "`get_registry`"
   - "`add_block_ui`"
   - "`add_block_server`"
+  - "`block_input_check`"
+  - "`block_output_ptype`"
 
 - title: Server utilities
   desc: Shiny server elements
@@ -206,6 +208,7 @@ reference:
 
 news:
  releases:
+ - text: "blockr 0.0.3.9000"
  - text: "blockr 0.0.2.9031"
  - text: "blockr 0.0.2"
  - text: "blockr 0.0.1.9000"
diff --git a/vignettes/registry.Rmd b/vignettes/registry.Rmd
index aae517b8..7354b036 100644
--- a/vignettes/registry.Rmd
+++ b/vignettes/registry.Rmd
@@ -369,4 +369,4 @@ knitr::include_graphics("figures/cmdk-data")
 
 ```{r cmdk-empty, echo=FALSE, fig.cap='Scoutbar with data block stack', fig.align = 'center', out.width='50%'}
 knitr::include_graphics("figures/cmdk-transform")
-```
\ No newline at end of file
+```