diff --git a/CHANGELOG.md b/CHANGELOG.md
index 50b9a3f..f8595e4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 All notable changes to this project will be documented in this file.
 
+#### 3.1 (April 15, 2020)
+
+- Fixed width of Germandbls, cornerbracketleft, cornerbracketleft, negativeAcknowledge-control, cornerbracketleft.half, cornerbracketright.half [#1000]
+
 #### 3.0 (April 9, 2020)
 
 - Disabled ligatures in progress bars `[-> [--> [---> [=> [==> [===>` [#968]
diff --git a/FiraCode.glyphs b/FiraCode.glyphs
index 95bb422..43f325c 100644
--- a/FiraCode.glyphs
+++ b/FiraCode.glyphs
@@ -129,7 +129,7 @@ value = (
 );
 }
 );
-date = "2020-04-09 13:10:08 +0000";
+date = "2020-04-15 16:43:56 +0000";
 designer = "Carrois Corporate, Edenspiekermann AG, Nikita Prokopov";
 designerURL = "https://tonsky.me";
 familyName = "Fira Code";
@@ -5220,7 +5220,7 @@ unicode = 0218;
 {
 color = 3;
 glyphname = Germandbls;
-lastChange = "2020-04-05 21:57:02 +0000";
+lastChange = "2020-04-15 15:10:21 +0000";
 layers = (
 {
 layerId = "B67F0F2D-EC95-4CB8-966E-23AE86958A69";
@@ -5269,7 +5269,7 @@ nodes = (
 );
 }
 );
-width = 1198;
+width = 1200;
 },
 {
 layerId = "4B7A3BAF-EAD8-4024-9BEA-BB1DE86CFCFA";
@@ -60670,7 +60670,7 @@ unicode = 005D;
 {
 color = 6;
 glyphname = cornerbracketleft;
-lastChange = "2020-04-08 18:25:56 +0000";
+lastChange = "2020-04-15 15:13:23 +0000";
 layers = (
 {
 layerId = "B67F0F2D-EC95-4CB8-966E-23AE86958A69";
@@ -60687,7 +60687,7 @@ nodes = (
 );
 }
 );
-width = 1100;
+width = 1200;
 },
 {
 layerId = "4B7A3BAF-EAD8-4024-9BEA-BB1DE86CFCFA";
@@ -60704,7 +60704,7 @@ nodes = (
 );
 }
 );
-width = 1100;
+width = 1200;
 }
 );
 unicode = 300C;
@@ -60976,27 +60976,25 @@ width = 1200;
 {
 color = 6;
 glyphname = cornerbracketleft.half;
-lastChange = "2020-04-08 18:26:42 +0000";
+lastChange = "2020-04-15 16:42:32 +0000";
 layers = (
 {
 components = (
 {
 name = cornerbracketleft;
-transform = "{1, 0, 0, 1, -500, 0}";
 }
 );
 layerId = "B67F0F2D-EC95-4CB8-966E-23AE86958A69";
-width = 600;
+width = 1200;
 },
 {
 components = (
 {
 name = cornerbracketleft;
-transform = "{1, 0, 0, 1, -500, 0}";
 }
 );
 layerId = "4B7A3BAF-EAD8-4024-9BEA-BB1DE86CFCFA";
-width = 600;
+width = 1200;
 }
 );
 unicode = FF62;
@@ -61004,27 +61002,25 @@ unicode = FF62;
 {
 color = 6;
 glyphname = cornerbracketright.half;
-lastChange = "2020-04-08 18:26:35 +0000";
+lastChange = "2020-04-15 16:42:52 +0000";
 layers = (
 {
 components = (
 {
 name = cornerbracketright;
-transform = "{1, 0, 0, 1, -100, 0}";
 }
 );
 layerId = "B67F0F2D-EC95-4CB8-966E-23AE86958A69";
-width = 600;
+width = 1200;
 },
 {
 components = (
 {
 name = cornerbracketright;
-transform = "{1, 0, 0, 1, -100, 0}";
 }
 );
 layerId = "4B7A3BAF-EAD8-4024-9BEA-BB1DE86CFCFA";
-width = 600;
+width = 1200;
 }
 );
 unicode = FF63;
@@ -100960,7 +100956,7 @@ unicode = 240A;
 {
 color = 3;
 glyphname = "negativeAcknowledge-control";
-lastChange = "2020-04-05 21:57:02 +0000";
+lastChange = "2020-04-15 15:13:59 +0000";
 layers = (
 {
 components = (
@@ -100981,7 +100977,7 @@ transform = "{0.33, 0, 0, 0.33, 800, 458}";
 }
 );
 layerId = "B67F0F2D-EC95-4CB8-966E-23AE86958A69";
-width = 1188;
+width = 1200;
 },
 {
 components = (
@@ -118541,6 +118537,6 @@ oV = 98;
 };
 };
 };
-versionMajor = 3;
+versionMajor = 4;
 versionMinor = 0;
 }
diff --git a/clojure/fira_code/checks.clj b/clojure/fira_code/checks.clj
new file mode 100644
index 0000000..001b9d9
--- /dev/null
+++ b/clojure/fira_code/checks.clj
@@ -0,0 +1,26 @@
+(ns fira-code.checks
+  (:require
+   [clojure.string :as str]
+   [fira-code.coll :as coll]
+   [fira-code.glyphs :as glyphs]))
+
+
+(defn width-ok? [w]
+  (#{"0" 0 1200 2400} w))
+
+
+(defn widths [font]
+  (doseq [g     (:glyphs font)
+          :when (not= "0" (:export g))
+          l     (:layers g)
+          :let  [w (:width l)]
+          :when (not (width-ok? w))]
+    (println (str "WARN glyph '" (:glyphname g) "' layer '" (:id (glyphs/layer l)) "' has width=" (pr-str w))))
+  font)
+
+
+(defn -main [& args]
+  (let [path (or (first args) "FiraCode.glyphs")
+        font (glyphs/load path)]
+    (widths font)))
+
diff --git a/clojure/fira_code/glyphs.clj b/clojure/fira_code/glyphs.clj
index 27ec8fb..fbfa90d 100755
--- a/clojure/fira_code/glyphs.clj
+++ b/clojure/fira_code/glyphs.clj
@@ -162,10 +162,12 @@
    :Regular "UUID0"
    :Bold    "4B7A3BAF-EAD8-4024-9BEA-BB1DE86CFCFA"})
 
+
 (defn layer [l]
-  { :id (case (:layerId l)
-          ((:Regular weights)) "Regular"
-          ((:Bold weights))    "Bold"
+  { :id (condp = (:layerId l)
+          (:Light weights)   "Light"
+          (:Regular weights) "Regular"
+          (:Bold weights)    "Bold"
           (:layerId l))
     :width (:width l) })
 
diff --git a/clojure/fira_code/main.clj b/clojure/fira_code/main.clj
index c077053..978d232 100644
--- a/clojure/fira_code/main.clj
+++ b/clojure/fira_code/main.clj
@@ -3,6 +3,7 @@
    [clojure.string :as str]
    [fira-code.calt :as calt]
    [fira-code.coll :as coll]
+   [fira-code.checks :as checks]
    [fira-code.glyphs :as glyphs]
    [fira-code.not-space :as not-space]
    [fira-code.spacers :as spacers]
@@ -22,6 +23,7 @@
         font'  (-> font
                  (calt/replace-calt ligas)
                  (spacers/add-spacers ligas)
-                 (not-space/regen-not-space))]
+                 (not-space/regen-not-space)
+                 (checks/widths))]
     (glyphs/save! path font')
     (println)))
\ No newline at end of file
diff --git a/script/check_widths b/script/check_widths
new file mode 100755
index 0000000..9253fe9
--- /dev/null
+++ b/script/check_widths
@@ -0,0 +1,3 @@
+#!/bin/zsh -euo pipefail
+
+clojure -m fira-code.checks
\ No newline at end of file