diff --git a/.travis.yml b/.travis.yml
index 3b3d44a..80d9f04 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,7 +8,7 @@ install:
   - go get github.com/udhos/lockfile
   - go get github.com/udhos/equalfile
   - go get github.com/udhos/difflib
-  - go get gopkg.in/yaml.v2
+  - go get gopkg.in/yaml.v3
   - go get golang.org/x/crypto/ssh
   - go get github.com/aws/aws-sdk-go/aws
 
diff --git a/README.md b/README.md
index 58208f2..f143896 100644
--- a/README.md
+++ b/README.md
@@ -69,21 +69,13 @@ Quick Start - Short version
 
 This is how to boot up Jazigo very quickly:
 
-## With Go Modules (starting from Go 1.11)
-
     git clone https://github.com/udhos/jazigo ;# clone outside of GOPATH
     cd jazigo
     go install ./jazigo
     mkdir etc repo log
     JAZIGO_HOME=$PWD ~/go/bin/jazigo
 
-## Without Go Modules (before Go 1.11)
-
-    go get github.com/udhos/jazigo
-    cd ~/go/src/github.com/udhos/jazigo
-    ./build.sh
-    mkdir etc repo log
-    JAZIGO_HOME=$PWD ~/go/bin/jazigo
+Open jazigo interface - http://localhost:8080/jazigo/
 
 Quick Start - Detailed version
 ==============================
@@ -92,34 +84,15 @@ Installation and usage are supposed to be dead simple. If you hit any surprising
 
 If you want to build from source code, start from step 1.
 
-If you downloaded the executable binary file, start from step 5.
-
-1\. Setup GOPATH as usual
-
-Example:
+If you downloaded the executable binary file, start from step 2.
 
-    #export GOPATH=~/go ;# starting from Go 1.8, GOPATH is no longer required
-    mkdir ~/go
+1\. Build from source
 
-2\. Get dependencies
-
-    go get github.com/icza/gowut/gwu
-    go get github.com/udhos/lockfile
-    go get github.com/udhos/equalfile
-    go get github.com/udhos/difflib
-    go get gopkg.in/yaml.v2
-    go get golang.org/x/crypto/ssh
-    go get github.com/aws/aws-sdk-go
-
-3\. Get source code
-
-    go get github.com/udhos/jazigo
-
-4\. Compile and install
-
-    go install github.com/udhos/jazigo/jazigo
+    git clone https://github.com/udhos/jazigo
+    cd jazigo
+    go install ./...
 
-5\. Decide where to store config, backup, log and static www files
+2\. Decide where to store config, backup, log and static www files
 
 Example:
 
@@ -133,7 +106,7 @@ By default, Jazigo looks for directories 'etc', 'repo', 'log', and 'www' under $
 If left undefined, JAZIGO_HOME defaults to /var/jazigo.
 See command line options to fine tune filesystem locations.
 
-6\. Copy static files (CSS and images) to $JAZIGO_HOME/www
+3\. Copy static files (CSS and images) to $JAZIGO_HOME/www
 
 Example:
 
@@ -147,7 +120,7 @@ Example:
     wget https://raw.githubusercontent.com/udhos/jazigo/master/www/jazigo.css
     wget https://raw.githubusercontent.com/udhos/jazigo/master/www/GitHub-Mark-32px.png
 
-7\. Run jazigo once (see -runOnce option)
+4\. Run jazigo once (see -runOnce option)
 
 `$GOPATH/bin/jazigo -runOnce`
 
@@ -155,11 +128,11 @@ Watch messages logged to standard output for errors.
 
 Hint: Since root privileges are usually not needed, run Jazigo as a regular user.
 
-8\. Run jazigo forever
+5\. Run jazigo forever
 
 `$GOPATH/bin/jazigo -disableStdoutLog`
 
-9\. Open the web interface
+6\. Open the web interface
 
 Point web browser at: [http://localhost:8080/jazigo](http://localhost:8080/jazigo)
       
diff --git a/build.sh b/build.sh
index 93ff0de..ddd6272 100755
--- a/build.sh
+++ b/build.sh
@@ -1,92 +1,23 @@
-#!/bin/sh
+#!/bin/bash
 
-step=0
+go install golang.org/x/vuln/cmd/govulncheck@latest
 
-msg() {
-    step=$((step+1))
-    echo >&2 $step. $*
-}
+gofmt -s -w .
 
-get() {
-    i=$1
-    msg fetching $i
-    go get $i
-    msg fetching $i - done
-}
+revive ./...
 
-get github.com/icza/gowut/gwu
-get github.com/udhos/difflib
-get github.com/udhos/lockfile
-get github.com/udhos/equalfile
-get gopkg.in/yaml.v2
-get golang.org/x/crypto/ssh
-get github.com/aws/aws-sdk-go
-#get honnef.co/go/simple/cmd/gosimple
-#get honnef.co/go/tools/cmd/staticcheck
+#gocyclo -over 15 .
 
-src=`find . -type f | egrep '\.go$'`
+go mod tidy
 
-msg fmt
-gofmt -s -w $src
-msg fix
-go tool fix $src
-msg vet
-go tool vet .
+govulncheck ./...
 
-msg install
-pkg=github.com/udhos/jazigo
-go install $pkg/jazigo
+go env -w CGO_ENABLED=1
 
-# go get honnef.co/go/simple/cmd/gosimple
-s=$GOPATH/bin/gosimple
-simple() {
-    msg simple - this is slow, please standby
-    # gosimple cant handle source files from multiple packages
-    $s jazigo/*.go
-    $s conf/*.go
-    $s dev/*.go
-    $s store/*.go
-    $s temp/*.go
-}
-[ -x "$s" ] && simple
+go test -race ./...
 
-# go get github.com/golang/lint/golint
-l=$GOPATH/bin/golint
-lint() {
-    msg lint
-    # golint cant handle source files from multiple packages
-    $l jazigo/*.go
-    $l conf/*.go
-    $l dev/*.go
-    $l store/*.go
-    $l temp/*.go
-}
-[ -x "$l" ] && lint
+go env -w CGO_ENABLED=0
 
-# go get honnef.co/go/tools/cmd/staticcheck
-sc=$GOPATH/bin/staticcheck
-static() {
-    msg staticcheck - this is slow, please standby
-    # staticcheck cant handle source files from multiple packages
-    $sc jazigo/*.go
-    $sc conf/*.go
-    $sc dev/*.go
-    $sc store/*.go
-    $sc temp/*.go
-}
-[ -x "$sc" ] && static
+go install ./...
 
-msg test dev - this may take a while, please stand by
-go test github.com/udhos/jazigo/dev
-
-msg test store
-if [ -z "$JAZIGO_S3_REGION" ]; then
-    echo >&2 JAZIGO_S3_REGION undefined -- for S3 testing, set JAZIGO_S3_REGION=region
-fi
-if [ -z "$JAZIGO_S3_FOLDER" ]; then
-    echo >&2 JAZIGO_S3_FOLDER undefined -- for S3 testing, set JAZIGO_S3_FOLDER=bucket/folder
-fi
-go test github.com/udhos/jazigo/store
-
-msg test jazigo
-go test github.com/udhos/jazigo/jazigo
+go env -u CGO_ENABLED
\ No newline at end of file
diff --git a/conf/conf.go b/conf/conf.go
index 032caf6..967d6af 100644
--- a/conf/conf.go
+++ b/conf/conf.go
@@ -1,9 +1,10 @@
+// Package conf handles configuration.
 package conf
 
 import (
 	"time"
 
-	"gopkg.in/yaml.v2"
+	"gopkg.in/yaml.v3"
 
 	"github.com/udhos/jazigo/store"
 )
diff --git a/dev/control.go b/dev/control.go
index 37773ee..a89d4c8 100644
--- a/dev/control.go
+++ b/dev/control.go
@@ -1,3 +1,4 @@
+// Package dev provides access to multiple devices.
 package dev
 
 import (
diff --git a/dev/model_fortios.go b/dev/model_fortios.go
index 12d95ed..c536188 100644
--- a/dev/model_fortios.go
+++ b/dev/model_fortios.go
@@ -22,9 +22,9 @@ func registerModelFortiOS(logger hasPrintf, t *DeviceTable) {
 		"config system global",  // enter config: valid only for vdom
 		"config system console", // enter config: valid only for non-vdom
 		"set output standard",   // disable paging
-		"end",               // exit config
-		"get system status", // system information
-		"show",              // get configuration
+		"end",                   // exit config
+		"get system status",     // system information
+		"show",                  // get configuration
 	}
 
 	promptPattern := `\S+\s#\s$` // "hostname # "
diff --git a/go.mod b/go.mod
index e679d6f..d8c2816 100644
--- a/go.mod
+++ b/go.mod
@@ -2,22 +2,25 @@ module github.com/udhos/jazigo
 
 require (
 	github.com/aws/aws-sdk-go v1.15.16
+	github.com/icza/gowut v1.3.0
+	github.com/udhos/difflib v0.0.0-20170223180222-9237ff6aafff
+	github.com/udhos/equalfile v0.0.0-20180725151512-a22d6261a8df
+	github.com/udhos/lockfile v0.0.0-20160928001432-1d49c987357a
+	golang.org/x/crypto v0.9.0
+	gopkg.in/yaml.v3 v3.0.1
+)
+
+require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-ini/ini v1.25.4 // indirect
 	github.com/gopherjs/gopherjs v0.0.0-20180820052304-89baedc74dd7 // indirect
-	github.com/icza/gowut v1.3.0
+	github.com/jmespath/go-jmespath v0.0.0-20160202185014-0b12d6b521d8 // indirect
 	github.com/jtolds/gls v4.2.1+incompatible // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/smartystreets/assertions v0.0.0-20180820201707-7c9eb446e3cf // indirect
 	github.com/smartystreets/goconvey v0.0.0-20180222194500-ef6db91d284a // indirect
 	github.com/stretchr/testify v1.2.2 // indirect
-	github.com/udhos/difflib v0.0.0-20170223180222-9237ff6aafff
-	github.com/udhos/equalfile v0.0.0-20180725151512-a22d6261a8df
-	github.com/udhos/lockfile v0.0.0-20160928001432-1d49c987357a
-	golang.org/x/crypto v0.0.0-20180820150726-614d502a4dac
-	golang.org/x/net v0.0.0-20180821023952-922f4815f713 // indirect
-	golang.org/x/sys v0.0.0-20180821140842-3b58ed4ad339 // indirect
-	golang.org/x/text v0.3.0 // indirect
-	gopkg.in/yaml.v2 v2.2.1
+	golang.org/x/sys v0.8.0 // indirect
 )
 
-go 1.13
+go 1.20
diff --git a/go.sum b/go.sum
index 02e00d5..b8e41db 100644
--- a/go.sum
+++ b/go.sum
@@ -26,15 +26,14 @@ github.com/udhos/equalfile v0.0.0-20180725151512-a22d6261a8df h1:SDnf0lMzWQcbGOL
 github.com/udhos/equalfile v0.0.0-20180725151512-a22d6261a8df/go.mod h1:1LOX9HjdFMke7ryP3IPby09FkswyY5KzhhsT37wLz/Y=
 github.com/udhos/lockfile v0.0.0-20160928001432-1d49c987357a h1:286YGPLaLItW0JKx1IePghZEhuNLHNEGPOIsD+25Yx4=
 github.com/udhos/lockfile v0.0.0-20160928001432-1d49c987357a/go.mod h1:w5A2nWhTT88JgIVjPxgCNvD8yrXpXSckwYh924u8a0I=
-golang.org/x/crypto v0.0.0-20180820150726-614d502a4dac h1:7d7lG9fHOLdL6jZPtnV4LpI41SbohIJ1Atq7U991dMg=
-golang.org/x/crypto v0.0.0-20180820150726-614d502a4dac/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
-golang.org/x/net v0.0.0-20180821023952-922f4815f713 h1:rMJUcaDGbG+X967I4zGKCq5laYqcGKJmpB+3jhpOhPw=
-golang.org/x/net v0.0.0-20180821023952-922f4815f713/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
-golang.org/x/sys v0.0.0-20180821140842-3b58ed4ad339 h1:0w2EXzxbB03VAzqwe3csbadu4CPhMRtxCz/rjw9gkic=
-golang.org/x/sys v0.0.0-20180821140842-3b58ed4ad339/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/crypto v0.9.0 h1:LF6fAI+IutBocDJ2OT0Q1g8plpYljMZ4+lty+dsqw3g=
+golang.org/x/crypto v0.9.0/go.mod h1:yrmDGqONDYtNj3tH8X9dzUun2m2lzPa9ngI6/RUPGR0=
+golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.8.0 h1:n5xxQn2i3PC0yLAbjTpNT85q/Kgzcr2gIoX9OrJUols=
+golang.org/x/text v0.9.0 h1:2sjJmO8cDvYveuX97RDLsxlyUxLl+GHoLxBiRdHllBE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
-gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/jazigo/doc.go b/jazigo/doc.go
index 3bcb432..af77d45 100644
--- a/jazigo/doc.go
+++ b/jazigo/doc.go
@@ -6,49 +6,51 @@ Jazigo is a tool written in Go for retrieving configuration for multiple network
 See also: https://github.com/udhos/jazigo
 
 Usage:
-        jazigo [flag]
+
+	jazigo [flag]
 
 Flags are:
-  -configPathPrefix string
-        configuration path prefix
-  -deviceDelete
-        delete devices specified in stdin
-  -deviceImport
-        import devices from stdin
-  -deviceList
-        list devices to stdout
-  -devicePurge
-        purge devices specified in stdin
-  -disableStdoutLog
-        disable logging to stdout
-  -logCheckInterval duration
-        interval for checking log file size
-  -logMaxFiles int
-        number of log files to keep
-  -logMaxSize int
-        size limit for log file
-  -logPathPrefix string
-        log path prefix
-  -repositoryPath string
-        repository path
-  -runOnce
-        exit after scanning all devices once
-  -s3region string
-        AWS S3 region
-  -webListen string
-        address:port for web UI
-  -wwwStaticPath string
-        directory for static www content
+
+	-configPathPrefix string
+	      configuration path prefix
+	-deviceDelete
+	      delete devices specified in stdin
+	-deviceImport
+	      import devices from stdin
+	-deviceList
+	      list devices to stdout
+	-devicePurge
+	      purge devices specified in stdin
+	-disableStdoutLog
+	      disable logging to stdout
+	-logCheckInterval duration
+	      interval for checking log file size
+	-logMaxFiles int
+	      number of log files to keep
+	-logMaxSize int
+	      size limit for log file
+	-logPathPrefix string
+	      log path prefix
+	-repositoryPath string
+	      repository path
+	-runOnce
+	      exit after scanning all devices once
+	-s3region string
+	      AWS S3 region
+	-webListen string
+	      address:port for web UI
+	-wwwStaticPath string
+	      directory for static www content
 
 By default, jazigo looks for these path prefixes under $JAZIGO_HOME:
-  etc/jazigo.conf. (can be overridden with -configPathPrefix)
-  log/jazigo.log.  (can be overridden with -logPathPrefix)
-  repo             (can be overridden with -repositoryPath)
-  www              (can be overridden with -wwwStaticPath)
+
+	etc/jazigo.conf. (can be overridden with -configPathPrefix)
+	log/jazigo.log.  (can be overridden with -logPathPrefix)
+	repo             (can be overridden with -repositoryPath)
+	www              (can be overridden with -wwwStaticPath)
 
 If $JAZIGO_HOME is not defined, jazigo home defaults to /var/jazigo.
 
 Since root privileges are usually not needed, run the jazigo application as a regular user.
-
 */
 package main
diff --git a/jazigo/main.go b/jazigo/main.go
index d38f251..cc78d90 100644
--- a/jazigo/main.go
+++ b/jazigo/main.go
@@ -1,3 +1,4 @@
+// Package main implements the jazigo tool.
 package main
 
 import (
@@ -21,7 +22,7 @@ import (
 )
 
 const appName = "jazigo"
-const appVersion = "0.11"
+const appVersion = "0.11.0"
 
 type app struct {
 	configPathPrefix string
diff --git a/old-build.sh b/old-build.sh
new file mode 100755
index 0000000..ddd6b69
--- /dev/null
+++ b/old-build.sh
@@ -0,0 +1,92 @@
+#!/bin/sh
+
+step=0
+
+msg() {
+    step=$((step+1))
+    echo >&2 $step. $*
+}
+
+get() {
+    i=$1
+    msg fetching $i
+    go get $i
+    msg fetching $i - done
+}
+
+get github.com/icza/gowut/gwu
+get github.com/udhos/difflib
+get github.com/udhos/lockfile
+get github.com/udhos/equalfile
+get gopkg.in/yaml.v3
+get golang.org/x/crypto/ssh
+get github.com/aws/aws-sdk-go
+#get honnef.co/go/simple/cmd/gosimple
+#get honnef.co/go/tools/cmd/staticcheck
+
+src=`find . -type f | egrep '\.go$'`
+
+msg fmt
+gofmt -s -w $src
+msg fix
+go tool fix $src
+msg vet
+go tool vet .
+
+msg install
+pkg=github.com/udhos/jazigo
+go install $pkg/jazigo
+
+# go get honnef.co/go/simple/cmd/gosimple
+s=$GOPATH/bin/gosimple
+simple() {
+    msg simple - this is slow, please standby
+    # gosimple cant handle source files from multiple packages
+    $s jazigo/*.go
+    $s conf/*.go
+    $s dev/*.go
+    $s store/*.go
+    $s temp/*.go
+}
+[ -x "$s" ] && simple
+
+# go get github.com/golang/lint/golint
+l=$GOPATH/bin/golint
+lint() {
+    msg lint
+    # golint cant handle source files from multiple packages
+    $l jazigo/*.go
+    $l conf/*.go
+    $l dev/*.go
+    $l store/*.go
+    $l temp/*.go
+}
+[ -x "$l" ] && lint
+
+# go get honnef.co/go/tools/cmd/staticcheck
+sc=$GOPATH/bin/staticcheck
+static() {
+    msg staticcheck - this is slow, please standby
+    # staticcheck cant handle source files from multiple packages
+    $sc jazigo/*.go
+    $sc conf/*.go
+    $sc dev/*.go
+    $sc store/*.go
+    $sc temp/*.go
+}
+[ -x "$sc" ] && static
+
+msg test dev - this may take a while, please stand by
+go test github.com/udhos/jazigo/dev
+
+msg test store
+if [ -z "$JAZIGO_S3_REGION" ]; then
+    echo >&2 JAZIGO_S3_REGION undefined -- for S3 testing, set JAZIGO_S3_REGION=region
+fi
+if [ -z "$JAZIGO_S3_FOLDER" ]; then
+    echo >&2 JAZIGO_S3_FOLDER undefined -- for S3 testing, set JAZIGO_S3_FOLDER=bucket/folder
+fi
+go test github.com/udhos/jazigo/store
+
+msg test jazigo
+go test github.com/udhos/jazigo/jazigo
diff --git a/store/mock_filesystem.go b/store/mock_filesystem.go
index 09d0320..0f7568f 100644
--- a/store/mock_filesystem.go
+++ b/store/mock_filesystem.go
@@ -1,3 +1,4 @@
+// Package store abstracts a file system.
 package store
 
 import (
diff --git a/store/s3.go b/store/s3.go
index efeeb88..f47d2a4 100644
--- a/store/s3.go
+++ b/store/s3.go
@@ -95,7 +95,8 @@ func s3path(path string) bool {
 	return s3match
 }
 
-//  Input: "arn:aws:s3:region::bucket/folder/file.xxx"
+//	Input: "arn:aws:s3:region::bucket/folder/file.xxx"
+//
 // Output: "region", "bucket", "folder/file.xxx"
 func s3parse(path string) (string, string, string) {
 	s := strings.Split(path, ":")
diff --git a/temp/temp.go b/temp/temp.go
index b160122..b3ea39d 100644
--- a/temp/temp.go
+++ b/temp/temp.go
@@ -1,3 +1,4 @@
+// Package temp creates temporary repository.
 package temp
 
 import (
@@ -7,7 +8,7 @@ import (
 
 const tempRepoPrefix = "/tmp/tmp-jazigo-repo"
 
-// MakeTempRepo creates the remporary repository path, for testing.
+// MakeTempRepo creates the temporary repository path, for testing.
 func MakeTempRepo() string {
 	path := tempRepoPrefix
 	if err := os.MkdirAll(path, 0700); err != nil {
@@ -16,7 +17,7 @@ func MakeTempRepo() string {
 	return path
 }
 
-// CleanupTempRepo erases the remporary repository path.
+// CleanupTempRepo erases the temporary repository path.
 func CleanupTempRepo() string {
 	path := tempRepoPrefix
 	if err := os.RemoveAll(path); err != nil {