diff --git a/.zenodo.json b/.zenodo.json
index 3afdaa3..4501f17 100644
--- a/.zenodo.json
+++ b/.zenodo.json
@@ -1,8 +1,8 @@
 {
-    "title": "mmcloughlin/addchain: v0.3.0",
+    "title": "mmcloughlin/addchain: v0.4.0",
     "description": "Cryptographic Addition Chain Generation in Go",
-    "version": "0.3.0",
-    "publication_date": "2021-05-13",
+    "version": "0.4.0",
+    "publication_date": "2021-10-30",
     "upload_type": "software",
     "access_right": "open",
     "license": "BSD-3-Clause",
@@ -14,7 +14,7 @@
     ],
     "related_identifiers": [
         {
-            "identifier": "https://github.com/mmcloughlin/addchain/tree/v0.3.0",
+            "identifier": "https://github.com/mmcloughlin/addchain/tree/v0.4.0",
             "relation": "isSupplementTo",
             "scheme": "url"
         }
diff --git a/CITATION.bib b/CITATION.bib
index 19fec23..4bddef6 100644
--- a/CITATION.bib
+++ b/CITATION.bib
@@ -2,10 +2,10 @@ @misc{addchain
     title        = {addchain: Cryptographic Addition Chain Generation in Go},
     author       = {Michael B. McLoughlin},
     year         = 2021,
-    month        = may,
+    month        = oct,
     howpublished = {Repository \url{https://github.com/mmcloughlin/addchain}},
-    version      = {0.3.0},
+    version      = {0.4.0},
     license      = {BSD 3-Clause License},
-    doi          = {10.5281/zenodo.4758226},
-    url          = {https://doi.org/10.5281/zenodo.4758226},
+    doi          = {10.5281/zenodo.5622943},
+    url          = {https://doi.org/10.5281/zenodo.5622943},
 }
diff --git a/CITATION.cff b/CITATION.cff
index 2503940..252327d 100644
--- a/CITATION.cff
+++ b/CITATION.cff
@@ -5,15 +5,15 @@ authors:
   - family-names: "McLoughlin"
     given-names: "Michael Ben"
     orcid: "https://orcid.org/0000-0003-2347-6258"
-version: "0.3.0"
-date-released: "2021-05-13"
+version: "0.4.0"
+date-released: "2021-10-30"
 license: BSD-3-Clause
 repository-code: https://github.com/mmcloughlin/addchain
-doi: "10.5281/zenodo.4758226"
+doi: "10.5281/zenodo.5622943"
 identifiers:
   - type: doi
     value: "10.5281/zenodo.4625263"
     description: "The concept DOI of the work."
   - type: doi
-    value: "10.5281/zenodo.4758226"
-    description: "The versioned DOI for version 0.3.0 of the work."
+    value: "10.5281/zenodo.5622943"
+    description: "The versioned DOI for version 0.4.0 of the work."
diff --git a/README.md b/README.md
index ad2987c..6a1664d 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
   <img src="https://img.shields.io/github/workflow/status/mmcloughlin/addchain/ci/master.svg?style=flat-square" alt="Build Status" />
   <a href="https://pkg.go.dev/github.com/mmcloughlin/addchain"><img src="https://img.shields.io/badge/doc-reference-007d9b?logo=go&style=flat-square" alt="go.dev" /></a>
   <a href="https://goreportcard.com/report/github.com/mmcloughlin/addchain"><img src="https://goreportcard.com/badge/github.com/mmcloughlin/addchain?style=flat-square" alt="Go Report Card" /></a>
-  <a href="https://doi.org/10.5281/zenodo.4758226"><img src="https://img.shields.io/badge/DOI-10.5281%2Fzenodo.4758226-007ec6?style=flat-square" alt="DOI: 10.5281/zenodo.4758226" /></a>
+  <a href="https://doi.org/10.5281/zenodo.5622943"><img src="https://img.shields.io/badge/DOI-10.5281%2Fzenodo.5622943-007ec6?style=flat-square" alt="DOI: 10.5281/zenodo.5622943" /></a>
 </p>
 
 <p align="center">Cryptographic Addition Chain Generation in Go</p>
@@ -357,20 +357,20 @@ chains](https://github.com/mmcloughlin/addchain/issues/24)?
 If you use `addchain` in your research a citation would be appreciated.
 Citing a specific release is preferred, since they are [archived on
 Zenodo](https://doi.org/10.5281/zenodo.4625263) and assigned a DOI. Please use the
-following BibTeX to cite the most recent [0.3.0
-release](https://github.com/mmcloughlin/addchain/releases/tag/v0.3.0).
+following BibTeX to cite the most recent [0.4.0
+release](https://github.com/mmcloughlin/addchain/releases/tag/v0.4.0).
 
 ```bib
 @misc{addchain,
     title        = {addchain: Cryptographic Addition Chain Generation in Go},
     author       = {Michael B. McLoughlin},
     year         = 2021,
-    month        = may,
+    month        = oct,
     howpublished = {Repository \url{https://github.com/mmcloughlin/addchain}},
-    version      = {0.3.0},
+    version      = {0.4.0},
     license      = {BSD 3-Clause License},
-    doi          = {10.5281/zenodo.4758226},
-    url          = {https://doi.org/10.5281/zenodo.4758226},
+    doi          = {10.5281/zenodo.5622943},
+    url          = {https://doi.org/10.5281/zenodo.5622943},
 }
 ```
 
diff --git a/doc/gen.md b/doc/gen.md
index 0e350b7..f19b047 100644
--- a/doc/gen.md
+++ b/doc/gen.md
@@ -155,7 +155,7 @@ func (z *Elt) Inv(x *Elt) *Elt {
 	//
 	// Operations: 254 squares 12 multiplies
 	//
-	// Generated by github.com/mmcloughlin/addchain v0.3.0.
+	// Generated by github.com/mmcloughlin/addchain v0.4.0.
 
 	// Allocate Temporaries.
 	var (
diff --git a/internal/examples/fp25519/inv.go b/internal/examples/fp25519/inv.go
index b3f8ada..ef8120e 100644
--- a/internal/examples/fp25519/inv.go
+++ b/internal/examples/fp25519/inv.go
@@ -23,7 +23,7 @@ func (z *Elt) Inv(x *Elt) *Elt {
 	//
 	// Operations: 254 squares 12 multiplies
 	//
-	// Generated by github.com/mmcloughlin/addchain v0.3.0.
+	// Generated by github.com/mmcloughlin/addchain v0.4.0.
 
 	// Allocate Temporaries.
 	var (
diff --git a/meta/vars.go b/meta/vars.go
index fb6fe71..a034e8c 100644
--- a/meta/vars.go
+++ b/meta/vars.go
@@ -2,9 +2,9 @@ package meta
 
 var (
 	buildversion   = ""
-	releaseversion = "0.3.0"
-	releasedate    = "2021-05-13"
+	releaseversion = "0.4.0"
+	releasedate    = "2021-10-30"
 	conceptdoi     = "10.5281/zenodo.4625263"
-	doi            = "10.5281/zenodo.4758226"
-	zenodoid       = "4758226"
+	doi            = "10.5281/zenodo.5622943"
+	zenodoid       = "5622943"
 )