diff --git a/CHANGELOG.md b/CHANGELOG.md
index bb2f1be7..f12d2670 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,18 +9,26 @@ and this project adheres to
 
 ## [Unreleased]
 
+<!--
+## [v0.105.0] - 2020-12-21
+-->
+
 ### Added
 
+- `$dnstype` modifier for filters [#2337].
 - HTTP API request body size limit [#2305].
 
 [#2305]: https://github.com/AdguardTeam/AdGuardHome/issues/2305
+[#2337]: https://github.com/AdguardTeam/AdGuardHome/issues/2337
 
 ### Changed
 
+- Our snap package now uses the `core20` image as its base [#2306].
 - Various internal improvements ([#2271], [#2297]).
 
 [#2271]: https://github.com/AdguardTeam/AdGuardHome/issues/2271
 [#2297]: https://github.com/AdguardTeam/AdGuardHome/issues/2297
+[#2306]: https://github.com/AdguardTeam/AdGuardHome/issues/2306
 
 
 
diff --git a/HACKING.md b/HACKING.md
index bbd4dfbd..bf56c270 100644
--- a/HACKING.md
+++ b/HACKING.md
@@ -47,6 +47,9 @@ The rules are mostly sorted in the alphabetical order.
  *  Document everything, including unexported top-level identifiers, to build
     a habit of writing documentation.
 
+ *  Constructors should validate their arguments and return meaningful errors.
+    As a corollary, avoid lazy initialization.
+
  *  Don't put variable names into any kind of quotes.
 
  *  Don't use naked `return`s.