diff --git a/.github/ISSUE_TEMPLATE/bug_report.md b/.github/ISSUE_TEMPLATE/bug_report.md
new file mode 100644
index 0000000..b3c2870
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/bug_report.md
@@ -0,0 +1,21 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+If feasible/relevant, please provide a code snippet (inline or with Go playground) to reproduce the issue.
+
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Additional context**
+Add any other context about the problem here.
diff --git a/.github/ISSUE_TEMPLATE/feature_request.md b/.github/ISSUE_TEMPLATE/feature_request.md
new file mode 100644
index 0000000..c89e51c
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/feature_request.md
@@ -0,0 +1,10 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+Please use discussions https://github.com/bool64/logz/discussions/categories/ideas to share feature ideas.
diff --git a/.github/ISSUE_TEMPLATE/question.md b/.github/ISSUE_TEMPLATE/question.md
new file mode 100644
index 0000000..ed600c7
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/question.md
@@ -0,0 +1,10 @@
+---
+name: Question
+about: Any question about features or usage
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+Please use discussions https://github.com/bool64/logz/discussions/categories/q-a to make your question more discoverable by other folks.
diff --git a/.github/workflows/bench.yml b/.github/workflows/bench.yml
index b6cb223..bd4fb36 100644
--- a/.github/workflows/bench.yml
+++ b/.github/workflows/bench.yml
@@ -12,27 +12,43 @@ on:
         description: 'New Ref'
         required: true
 
+# Cancel the workflow in progress in newer build is about to start.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 env:
   GO111MODULE: "on"
   CACHE_BENCHMARK: "off"    # Enables benchmark result reuse between runs, may skew latency results.
   RUN_BASE_BENCHMARK: "on"  # Runs benchmark for PR base in case benchmark result is missing.
+  GO_VERSION: 1.20.x
 jobs:
   bench:
-    strategy:
-      matrix:
-        go-version: [ 1.17.x ]
     runs-on: ubuntu-latest
     steps:
-      - name: Install Go
-        uses: actions/setup-go@v2
+      - name: Install Go stable
+        if: env.GO_VERSION != 'tip'
+        uses: actions/setup-go@v4
         with:
-          go-version: ${{ matrix.go-version }}
+          go-version: ${{ env.GO_VERSION }}
+
+      - name: Install Go tip
+        if: env.GO_VERSION == 'tip'
+        run: |
+          curl -sL https://storage.googleapis.com/go-build-snap/go/linux-amd64/$(git ls-remote https://github.com/golang/go.git HEAD | awk '{print $1;}').tar.gz -o gotip.tar.gz
+          ls -lah gotip.tar.gz
+          mkdir -p ~/sdk/gotip
+          tar -C ~/sdk/gotip -xzf gotip.tar.gz
+          ~/sdk/gotip/bin/go version
+          echo "PATH=$HOME/go/bin:$HOME/sdk/gotip/bin/:$PATH" >> $GITHUB_ENV
+
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           ref: ${{ (github.event.inputs.new != '') && github.event.inputs.new || github.event.ref }}
+
       - name: Go cache
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           # In order:
           # * Module download cache
@@ -43,49 +59,58 @@ jobs:
           key: ${{ runner.os }}-go-cache-${{ hashFiles('**/go.sum') }}
           restore-keys: |
             ${{ runner.os }}-go-cache
+
       - name: Restore benchstat
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: ~/go/bin/benchstat
-          key: ${{ runner.os }}-benchstat
+          key: ${{ runner.os }}-benchstat-legacy
+
       - name: Restore base benchmark result
+        id: base-benchmark
         if: env.CACHE_BENCHMARK == 'on'
-        id: benchmark-base
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: |
             bench-master.txt
             bench-main.txt
           # Use base sha for PR or new commit hash for master/main push in benchmark result key.
           key: ${{ runner.os }}-bench-${{ (github.event.pull_request.base.sha != github.event.after) && github.event.pull_request.base.sha || github.event.after }}
-      - name: Checkout base code
-        if: env.RUN_BASE_BENCHMARK == 'on' && steps.benchmark-base.outputs.cache-hit != 'true' && (github.event.pull_request.base.sha != '' || github.event.inputs.old != '')
-        uses: actions/checkout@v2
-        with:
-          ref: ${{ (github.event.pull_request.base.sha != '' ) && github.event.pull_request.base.sha || github.event.inputs.old }}
-          path: __base
-      - name: Run base benchmark
-        if: env.RUN_BASE_BENCHMARK == 'on' && steps.benchmark-base.outputs.cache-hit != 'true' && (github.event.pull_request.base.sha != '' || github.event.inputs.old != '')
+
+      - name: Run benchmark
+        run: |
+          export REF_NAME=new
+          make bench
+          OUTPUT=$(make bench-stat-diff)
+          echo "${OUTPUT}"
+          echo "diff<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+          OUTPUT=$(make bench-stat)
+          echo "${OUTPUT}"
+          echo "result<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+
+      - name: Run benchmark for base code
+        if: env.RUN_BASE_BENCHMARK == 'on' && steps.base-benchmark.outputs.cache-hit != 'true' && (github.event.pull_request.base.sha != '' || github.event.inputs.old != '')
         run: |
+          git fetch origin master ${{ github.event.pull_request.base.sha }}
+          HEAD=$(git rev-parse HEAD)
+          git reset --hard ${{ github.event.pull_request.base.sha }}
           export REF_NAME=master
-          cd __base
-          make | grep bench-run && (BENCH_COUNT=5 make bench-run bench-stat && cp bench-master.txt ../bench-master.txt) || echo "No benchmarks in base"
-      - name: Benchmark
+          make bench-run bench-stat
+          git reset --hard $HEAD
+
+      - name: Benchmark stats
         id: bench
         run: |
           export REF_NAME=new
-          BENCH_COUNT=5 make bench
           OUTPUT=$(make bench-stat-diff)
-          OUTPUT="${OUTPUT//'%'/'%25'}"
-          OUTPUT="${OUTPUT//$'\n'/'%0A'}"
-          OUTPUT="${OUTPUT//$'\r'/'%0D'}"
-          echo "::set-output name=diff::$OUTPUT"
+          echo "${OUTPUT}"
+          echo "diff<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
           OUTPUT=$(make bench-stat)
-          OUTPUT="${OUTPUT//'%'/'%25'}"
-          OUTPUT="${OUTPUT//$'\n'/'%0A'}"
-          OUTPUT="${OUTPUT//$'\r'/'%0D'}"
-          echo "::set-output name=result::$OUTPUT"
-      - name: Comment Benchmark Result
+          echo "${OUTPUT}"
+          echo "result<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+
+      - name: Comment benchmark result
+        continue-on-error: true
         uses: marocchino/sticky-pull-request-comment@v2
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/cloc.yml b/.github/workflows/cloc.yml
index ed1ddb9..3f1fc19 100644
--- a/.github/workflows/cloc.yml
+++ b/.github/workflows/cloc.yml
@@ -2,30 +2,37 @@
 name: cloc
 on:
   pull_request:
+
+# Cancel the workflow in progress in newer build is about to start.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   cloc:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           path: pr
       - name: Checkout base code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           ref: ${{ github.event.pull_request.base.sha }}
           path: base
-      - name: Count Lines Of Code
+      - name: Count lines of code
         id: loc
         run: |
-          curl -OL https://github.com/vearutop/sccdiff/releases/download/v1.0.1/linux_amd64.tar.gz && tar xf linux_amd64.tar.gz
+          curl -sLO https://github.com/vearutop/sccdiff/releases/download/v1.0.3/linux_amd64.tar.gz && tar xf linux_amd64.tar.gz
+          sccdiff_hash=$(git hash-object ./sccdiff)
+          [ "$sccdiff_hash" == "ae8a07b687bd3dba60861584efe724351aa7ff63" ] || (echo "::error::unexpected hash for sccdiff, possible tampering: $sccdiff_hash" && exit 1)
           OUTPUT=$(cd pr && ../sccdiff -basedir ../base)
-          OUTPUT="${OUTPUT//'%'/'%25'}"
-          OUTPUT="${OUTPUT//$'\n'/'%0A'}"
-          OUTPUT="${OUTPUT//$'\r'/'%0D'}"
-          echo "::set-output name=diff::$OUTPUT"
+          echo "${OUTPUT}"
+          echo "diff<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
 
-      - name: Comment Code Lines
+      - name: Comment lines of code
+        continue-on-error: true
         uses: marocchino/sticky-pull-request-comment@v2
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/golangci-lint.yml b/.github/workflows/golangci-lint.yml
index cf9c148..e651212 100644
--- a/.github/workflows/golangci-lint.yml
+++ b/.github/workflows/golangci-lint.yml
@@ -8,17 +8,26 @@ on:
       - master
       - main
   pull_request:
+
+# Cancel the workflow in progress in newer build is about to start.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   golangci:
     name: golangci-lint
     runs-on: ubuntu-latest
     steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.20.x
       - uses: actions/checkout@v2
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v2.5.2
+        uses: golangci/golangci-lint-action@v3.4.0
         with:
           # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
-          version: v1.41.1
+          version: v1.51.1
 
           # Optional: working directory, useful for monorepos
           # working-directory: somedir
diff --git a/.github/workflows/gorelease.yml b/.github/workflows/gorelease.yml
index a733761..41767ba 100644
--- a/.github/workflows/gorelease.yml
+++ b/.github/workflows/gorelease.yml
@@ -2,43 +2,54 @@
 name: gorelease
 on:
   pull_request:
+
+# Cancel the workflow in progress in newer build is about to start.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 env:
-  GO111MODULE: "on"
+  GO_VERSION: 1.20.x
 jobs:
   gorelease:
-    strategy:
-      matrix:
-        go-version: [ 1.17.x ]
     runs-on: ubuntu-latest
     steps:
-      - name: Install Go
-        uses: actions/setup-go@v2
+      - name: Install Go stable
+        if: env.GO_VERSION != 'tip'
+        uses: actions/setup-go@v4
         with:
-          go-version: ${{ matrix.go-version }}
+          go-version: ${{ env.GO_VERSION }}
+      - name: Install Go tip
+        if: env.GO_VERSION == 'tip'
+        run: |
+          curl -sL https://storage.googleapis.com/go-build-snap/go/linux-amd64/$(git ls-remote https://github.com/golang/go.git HEAD | awk '{print $1;}').tar.gz -o gotip.tar.gz
+          ls -lah gotip.tar.gz
+          mkdir -p ~/sdk/gotip
+          tar -C ~/sdk/gotip -xzf gotip.tar.gz
+          ~/sdk/gotip/bin/go version
+          echo "PATH=$HOME/go/bin:$HOME/sdk/gotip/bin/:$PATH" >> $GITHUB_ENV
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Gorelease cache
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: |
             ~/go/bin/gorelease
-          key: ${{ runner.os }}-gorelease
+          key: ${{ runner.os }}-gorelease-generic
       - name: Gorelease
         id: gorelease
         run: |
           test -e ~/go/bin/gorelease || go install golang.org/x/exp/cmd/gorelease@latest
-          OUTPUT=$(gorelease || exit 0)
-          OUTPUT="${OUTPUT//'%'/'%25'}"
-          OUTPUT="${OUTPUT//$'\n'/'%0A'}"
-          OUTPUT="${OUTPUT//$'\r'/'%0D'}"
-          echo "::set-output name=report::$OUTPUT"
-      - name: Comment Report
+          OUTPUT=$(gorelease 2>&1 || exit 0)
+          echo "${OUTPUT}"
+          echo "report<<EOF" >> $GITHUB_OUTPUT && echo "$OUTPUT" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+      - name: Comment report
+        continue-on-error: true
         uses: marocchino/sticky-pull-request-comment@v2
         with:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           header: gorelease
           message: |
-            ### API Changes
+            ### Go API Changes
 
             <pre>
             ${{ steps.gorelease.outputs.report }}
diff --git a/.github/workflows/test-unit.yml b/.github/workflows/test-unit.yml
index 79ed0f6..2817dcc 100644
--- a/.github/workflows/test-unit.yml
+++ b/.github/workflows/test-unit.yml
@@ -6,24 +6,45 @@ on:
       - master
       - main
   pull_request:
+
+# Cancel the workflow in progress in newer build is about to start.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 env:
   GO111MODULE: "on"
   RUN_BASE_COVERAGE: "on"  # Runs test for PR base in case base test coverage is missing.
+  COV_GO_VERSION: 1.20.x   # Version of Go to collect coverage
+  TARGET_DELTA_COV: 90     # Target coverage of changed lines, in percents
 jobs:
   test:
     strategy:
       matrix:
-        go-version: [ 1.13.x, 1.14.x, 1.15.x, 1.16.x, 1.17.x ]
+        go-version: [ 1.13.x, 1.19.x, 1.20.x ]
     runs-on: ubuntu-latest
     steps:
-      - name: Install Go
-        uses: actions/setup-go@v2
+      - name: Install Go stable
+        if: matrix.go-version != 'tip'
+        uses: actions/setup-go@v4
         with:
           go-version: ${{ matrix.go-version }}
+
+      - name: Install Go tip
+        if: matrix.go-version == 'tip'
+        run: |
+          curl -sL https://storage.googleapis.com/go-build-snap/go/linux-amd64/$(git ls-remote https://github.com/golang/go.git HEAD | awk '{print $1;}').tar.gz -o gotip.tar.gz
+          ls -lah gotip.tar.gz
+          mkdir -p ~/sdk/gotip
+          tar -C ~/sdk/gotip -xzf gotip.tar.gz
+          ~/sdk/gotip/bin/go version
+          echo "PATH=$HOME/go/bin:$HOME/sdk/gotip/bin/:$PATH" >> $GITHUB_ENV
+
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
+
       - name: Go cache
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           # In order:
           # * Module download cache
@@ -34,42 +55,55 @@ jobs:
           key: ${{ runner.os }}-go-cache-${{ hashFiles('**/go.sum') }}
           restore-keys: |
             ${{ runner.os }}-go-cache
+
       - name: Restore base test coverage
-        if: matrix.go-version == '1.17.x'
+        id: base-coverage
+        if: matrix.go-version == env.COV_GO_VERSION && github.event.pull_request.base.sha != ''
         uses: actions/cache@v2
         with:
           path: |
             unit-base.txt
           # Use base sha for PR or new commit hash for master/main push in test result key.
           key: ${{ runner.os }}-unit-test-coverage-${{ (github.event.pull_request.base.sha != github.event.after) && github.event.pull_request.base.sha || github.event.after }}
-      - name: Checkout base code
-        if: matrix.go-version == '1.17.x' && env.RUN_BASE_COVERAGE == 'on' && steps.benchmark-base.outputs.cache-hit != 'true' && github.event.pull_request.base.sha != ''
-        uses: actions/checkout@v2
-        with:
-          ref: ${{ github.event.pull_request.base.sha }}
-          path: __base
+
       - name: Run test for base code
-        if: matrix.go-version == '1.17.x' && env.RUN_BASE_COVERAGE == 'on' && steps.benchmark-base.outputs.cache-hit != 'true' && github.event.pull_request.base.sha != ''
+        if: matrix.go-version == env.COV_GO_VERSION && env.RUN_BASE_COVERAGE == 'on' && steps.base-coverage.outputs.cache-hit != 'true' && github.event.pull_request.base.sha != ''
         run: |
-          cd __base
-          make | grep test-unit && (make test-unit && go tool cover -func=./unit.coverprofile | sed -e 's/.go:[0-9]*:\t/.go\t/g' | sed -e 's/\t\t*/\t/g'  > ../unit-base.txt) || echo "No test-unit in base"
+          git fetch origin master ${{ github.event.pull_request.base.sha }}
+          HEAD=$(git rev-parse HEAD)
+          git reset --hard ${{ github.event.pull_request.base.sha }}
+          (make test-unit && go tool cover -func=./unit.coverprofile > unit-base.txt) || echo "No test-unit in base"
+          git reset --hard $HEAD
+
       - name: Test
         id: test
         run: |
           make test-unit
-          go tool cover -func=./unit.coverprofile | sed -e 's/.go:[0-9]*:\t/.go\t/g' | sed -e 's/\t\t*/\t/g'  > unit.txt
-          OUTPUT=$(test -e unit-base.txt && (diff unit-base.txt unit.txt || exit 0) || cat unit.txt)
-          OUTPUT="${OUTPUT//'%'/'%25'}"
-          OUTPUT="${OUTPUT//$'\n'/'%0A'}"
-          OUTPUT="${OUTPUT//$'\r'/'%0D'}"
+          go tool cover -func=./unit.coverprofile > unit.txt
           TOTAL=$(grep 'total:' unit.txt)
-          echo "::set-output name=diff::$OUTPUT"
-          echo "::set-output name=total::$TOTAL"
-      - name: Store base coverage
-        if: ${{ github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main' }}
-        run: cp unit.txt unit-base.txt
-      - name: Comment Test Coverage
-        if: matrix.go-version == '1.17.x'
+          echo "${TOTAL}"
+          echo "total=$TOTAL" >> $GITHUB_OUTPUT
+
+      - name: Annotate missing test coverage
+        id: annotate
+        if: matrix.go-version == env.COV_GO_VERSION && github.event.pull_request.base.sha != ''
+        run: |
+          curl -sLO https://github.com/vearutop/gocovdiff/releases/download/v1.3.6/linux_amd64.tar.gz && tar xf linux_amd64.tar.gz
+          gocovdiff_hash=$(git hash-object ./gocovdiff)
+          [ "$gocovdiff_hash" == "8e507e0d671d4d6dfb3612309b72b163492f28eb" ] || (echo "::error::unexpected hash for gocovdiff, possible tampering: $gocovdiff_hash" && exit 1)
+          git fetch origin master ${{ github.event.pull_request.base.sha }}
+          REP=$(./gocovdiff -cov unit.coverprofile -gha-annotations gha-unit.txt -delta-cov-file delta-cov-unit.txt -target-delta-cov ${TARGET_DELTA_COV})
+          echo "${REP}"
+          cat gha-unit.txt
+          DIFF=$(test -e unit-base.txt && ./gocovdiff -func-cov unit.txt -func-base-cov unit-base.txt || echo "Missing base coverage file")
+          TOTAL=$(cat delta-cov-unit.txt)
+          echo "rep<<EOF" >> $GITHUB_OUTPUT && echo "$REP" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+          echo "diff<<EOF" >> $GITHUB_OUTPUT && echo "$DIFF" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+          echo "total<<EOF" >> $GITHUB_OUTPUT && echo "$TOTAL" >> $GITHUB_OUTPUT && echo "EOF" >> $GITHUB_OUTPUT
+
+      - name: Comment test coverage
+        continue-on-error: true
+        if: matrix.go-version == env.COV_GO_VERSION && github.event.pull_request.base.sha != ''
         uses: marocchino/sticky-pull-request-comment@v2
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -77,15 +111,25 @@ jobs:
           message: |
             ### Unit Test Coverage
             ${{ steps.test.outputs.total }}
+            ${{ steps.annotate.outputs.total }}
+            <details><summary>Coverage of changed lines</summary>
+            
+            ${{ steps.annotate.outputs.rep }}
+
+            </details>
+
             <details><summary>Coverage diff with base branch</summary>
 
-            ```diff
-            ${{ steps.test.outputs.diff }}
-            ```
+            ${{ steps.annotate.outputs.diff }}
+            
             </details>
 
+      - name: Store base coverage
+        if: ${{ github.ref == 'refs/heads/master' || github.ref == 'refs/heads/main' }}
+        run: cp unit.txt unit-base.txt
+
       - name: Upload code coverage
-        if: matrix.go-version == '1.17.x'
+        if: matrix.go-version == env.COV_GO_VERSION
         uses: codecov/codecov-action@v1
         with:
           file: ./unit.coverprofile
diff --git a/.golangci.yml b/.golangci.yml
index c203410..feb9910 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -20,6 +20,7 @@ linters-settings:
 linters:
   enable-all: true
   disable:
+    - containedctx
     - lll
     - maligned
     - gochecknoglobals
@@ -33,6 +34,18 @@ linters:
     - scopelint # deprecated
     - ifshort # too many false positives
     - golint # deprecated
+    - varnamelen
+    - tagliatelle
+    - errname
+    - ireturn
+    - exhaustruct
+    - nonamedreturns
+    - nosnakecase
+    - structcheck
+    - varcheck
+    - deadcode
+    - testableexamples
+    - dupword
 
 issues:
   exclude-use-default: false
@@ -44,5 +57,13 @@ issues:
         - noctx
         - funlen
         - dupl
+        - structcheck
+        - unused
+        - unparam
+        - nosnakecase
       path: "_test.go"
+    - linters:
+        - errcheck # Error checking omitted for brevity.
+        - gosec
+      path: "example_"
 
diff --git a/Makefile b/Makefile
index d60ee4b..053e982 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-#GOLANGCI_LINT_VERSION := "v1.41.1" # Optional configuration to pinpoint golangci-lint version.
+#GOLANGCI_LINT_VERSION := "v1.51.1" # Optional configuration to pinpoint golangci-lint version.
 
 # The head of Makefile determines location of dev-go to include standard targets.
 GO ?= go
@@ -23,7 +23,7 @@ ifeq ($(DEVGO_PATH),)
 	DEVGO_PATH := $(shell GO111MODULE=on $(GO) list ${modVendor} -f '{{.Dir}}' -m github.com/bool64/dev)
 	ifeq ($(DEVGO_PATH),)
     	$(info Module github.com/bool64/dev not found, downloading.)
-    	DEVGO_PATH := $(shell export GO111MODULE=on && $(GO) mod tidy && $(GO) list -f '{{.Dir}}' -m github.com/bool64/dev)
+    	DEVGO_PATH := $(shell export GO111MODULE=on && $(GO) get github.com/bool64/dev && $(GO) list -f '{{.Dir}}' -m github.com/bool64/dev)
 	endif
 endif
 
diff --git a/README.md b/README.md
index 0e726fb..9eab3ab 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,7 @@ They are useful for last mile observability of logs.
 * Adapter for [`go.uber.org/zap`](./zzap).
 * Adapter for [`github.com/bool64/ctxd`](./ctxz).
 * HTTP handler to serve aggregated messages.
+* Best effort [filtering](https://pkg.go.dev/github.com/vearutop/lograte/filter#Dynamic) of dynamic parts of messages.
 
 ![Screenshot](./_examples/screenshot.png)
 
@@ -30,6 +31,7 @@ zc := zap.NewDevelopmentConfig()
 zz, lo := zzap.NewOption(logz.Config{
     MaxCardinality: 5,
     MaxSamples:     10,
+	FilterMessage:  true,
 })
 
 l, err := zc.Build(zz)
@@ -41,6 +43,9 @@ l.Debug("starting example")
 l.Sugar().Infow("sample info", "one", 1, "two", 2)
 l.Error("unexpected end of the world")
 
+l.Warn("please be careful with asf872dfse732")
+l.Warn("please be careful with sdf890sdf0w9d") // These messages will be grouped together with help of filtering.
+
 l.Info("starting server at http://localhost:6060/")
 err = http.ListenAndServe("0.0.0.0:6060", logzpage.Handler(lo...))
 if err != nil {
diff --git a/_examples/screenshot.png b/_examples/screenshot.png
index fb15d85..eb6b553 100644
Binary files a/_examples/screenshot.png and b/_examples/screenshot.png differ
diff --git a/_examples/zzap/go.mod b/_examples/zzap/go.mod
index b744ed0..84f6378 100644
--- a/_examples/zzap/go.mod
+++ b/_examples/zzap/go.mod
@@ -1,11 +1,18 @@
 module zapage
 
-go 1.11
+go 1.17
 
 replace github.com/bool64/logz => ./../..
 
 require (
 	github.com/bool64/logz v0.0.0-00010101000000-000000000000
 	github.com/drhodes/golorem v0.0.0-20160418191928-ecccc744c2d9
-	go.uber.org/zap v1.16.0
+	go.uber.org/zap v1.24.0
+)
+
+require (
+	github.com/vearutop/dynhist-go v1.0.0 // indirect
+	github.com/vearutop/lograte v1.0.5 // indirect
+	go.uber.org/atomic v1.10.0 // indirect
+	go.uber.org/multierr v1.10.0 // indirect
 )
diff --git a/_examples/zzap/go.sum b/_examples/zzap/go.sum
index c43669f..e4b40d9 100644
--- a/_examples/zzap/go.sum
+++ b/_examples/zzap/go.sum
@@ -1,68 +1,79 @@
-github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
-github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
-github.com/bool64/dev v0.1.13 h1:edfquat4DBM1FBVMtm+z4Ksf1Du/S+qiAjslmE3xdIM=
-github.com/bool64/dev v0.1.13/go.mod h1:pn52JC52uSgpazChx9CeXyG+S3sW2V36HHoLNBbscdg=
+github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
+github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
+github.com/bool64/ctxd v1.2.1/go.mod h1:ZG6QkeGVLTiUl2mxPpyHmFhDzFZCyocr9hluBV3LYuc=
+github.com/bool64/dev v0.2.20/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/bool64/dev v0.2.24/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/bool64/dev v0.2.27 h1:mFT+B74mFVgUeUmm/EbfM6ELPA55lEXBjQ/AOHCwCOc=
+github.com/bool64/dev v0.2.27/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/drhodes/golorem v0.0.0-20160418191928-ecccc744c2d9 h1:EQOZw/LCQ0SM4sNez3EhUf9gQalQrLrs4mPtmQa+d58=
 github.com/drhodes/golorem v0.0.0-20160418191928-ecccc744c2d9/go.mod h1:NsKVpF4h4j13Vm6Cx7Kf0V03aJKjfaStvm5rvK4+FyQ=
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-github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
-github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
-github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
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 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
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 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
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 github.com/vearutop/dynhist-go v1.0.0 h1:SLYGcQMzmIoWnuqtF9lV8ULUBC735A56M5nL2CNth4c=
 github.com/vearutop/dynhist-go v1.0.0/go.mod h1:7Cgyu5Ww8FwdB+Y+zawRz9cQT5oXAxw294L9lQ+JI/k=
-go.uber.org/atomic v1.6.0/go.mod h1:sABNBOSYdrvTF6hTgEIbc7YasKWGhgEQZyfxyTvoXHQ=
-go.uber.org/atomic v1.7.0 h1:ADUqmZGgLDDfbSL9ZmPxKTybcoEYHgpYfELNoN+7hsw=
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+github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
-go.uber.org/multierr v1.5.0/go.mod h1:FeouvMocqHpRaaGuG9EjoKcStLC43Zu/fmqdUMPcKYU=
-go.uber.org/multierr v1.6.0 h1:y6IPFStTAIT5Ytl7/XYmHvzXQ7S3g/IeZW9hyZ5thw4=
+go.uber.org/atomic v1.10.0 h1:9qC72Qh0+3MqyJbAn8YU5xVq1frD8bn3JtD2oXtafVQ=
+go.uber.org/atomic v1.10.0/go.mod h1:LUxbIzbOniOlMKjJjyPfpl4v+PKK2cNJn91OQbhoJI0=
+go.uber.org/goleak v1.1.11 h1:wy28qYRKZgnJTxGxvye5/wgWr1EKjmUDGYox5mGlRlI=
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 go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=
-go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee/go.mod h1:vJERXedbb3MVM5f9Ejo0C68/HhF8uaILCdgjnY+goOA=
-go.uber.org/zap v1.16.0 h1:uFRZXykJGK9lLY4HtgSw44DnIcAM+kRBP7x5m+NpAOM=
-go.uber.org/zap v1.16.0/go.mod h1:MA8QOfq0BHJwdXa996Y4dYkAqRKB8/1K1QMMZVaNZjQ=
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 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
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-golang.org/x/lint v0.0.0-20190930215403-16217165b5de h1:5hukYrvBGR8/eNkX5mdUezrA6JiaEZDtJb9Ei+1LlBs=
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 golang.org/x/lint v0.0.0-20190930215403-16217165b5de/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
-golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
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 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
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 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
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 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
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 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
-golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
-golang.org/x/tools v0.0.0-20191029041327-9cc4af7d6b2c/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
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+golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
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 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
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 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.2.5 h1:ymVxjfMaHvXD8RqPRmzHHsB3VvucivSkIAvJFDI5O3c=
 gopkg.in/yaml.v2 v2.2.5/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
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-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-honnef.co/go/tools v0.0.1-2019.2.3 h1:3JgtbtFHMiCmsznwGVTUWbgGov+pVqnlf1dEJTNAXeM=
-honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
+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/_examples/zzap/main.go b/_examples/zzap/main.go
index c145264..7ea0ccc 100644
--- a/_examples/zzap/main.go
+++ b/_examples/zzap/main.go
@@ -3,6 +3,7 @@ package main
 import (
 	"math/rand"
 	"net/http"
+	"strconv"
 	"time"
 
 	"github.com/bool64/logz"
@@ -17,6 +18,7 @@ func main() {
 	zz, lo := zzap.NewOption(logz.Config{
 		MaxCardinality: 5,
 		MaxSamples:     10,
+		FilterMessage:  true,
 	})
 
 	l, err := zc.Build(zz)
@@ -53,7 +55,7 @@ func main() {
 					keysAndValues = append(keysAndValues, lorem.Word(3, 6), lorem.Word(3, 6))
 				}
 
-				lw.Sugar().Warnw(msg, keysAndValues...)
+				lw.Sugar().Warnw(msg+" Dynamic"+strconv.Itoa(i)+".", keysAndValues...)
 
 				time.Sleep(time.Duration(1e9 * rand.Float64()))
 			}
@@ -61,7 +63,7 @@ func main() {
 	}
 
 	l.Info("starting server at http://localhost:6060/")
-	err = http.ListenAndServe("0.0.0.0:6060", logzpage.Handler(lo...))
+	err = http.ListenAndServe("localhost:6060", logzpage.Handler(lo...))
 	if err != nil {
 		l.Fatal(err.Error())
 	}
diff --git a/go.mod b/go.mod
index eabc790..4a9d7a2 100644
--- a/go.mod
+++ b/go.mod
@@ -1,11 +1,20 @@
 module github.com/bool64/logz
 
-go 1.13
+go 1.17
 
 require (
-	github.com/bool64/ctxd v1.0.0
-	github.com/bool64/dev v0.1.41
-	github.com/stretchr/testify v1.7.0
+	github.com/bool64/ctxd v1.2.1
+	github.com/bool64/dev v0.2.27
+	github.com/stretchr/testify v1.8.2
 	github.com/vearutop/dynhist-go v1.0.0
-	go.uber.org/zap v1.19.0
+	github.com/vearutop/lograte v1.0.5
+	go.uber.org/zap v1.16.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.uber.org/atomic v1.6.0 // indirect
+	go.uber.org/multierr v1.5.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
diff --git a/go.sum b/go.sum
index 36fd1d5..3032f0c 100644
--- a/go.sum
+++ b/go.sum
@@ -1,14 +1,17 @@
-github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
-github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
-github.com/bool64/ctxd v1.0.0 h1:Btvo6BU5FulG7H2V9m5Il/2vcqT0nxe86AiEpbG08/I=
-github.com/bool64/ctxd v1.0.0/go.mod h1:+rjDVFNOJeO+xlvMqQfG0p53CzuRB7FhPSo5nWSkpQ0=
-github.com/bool64/dev v0.1.25/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
-github.com/bool64/dev v0.1.28/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
-github.com/bool64/dev v0.1.41 h1:L554LCQZc3d7mtcdPUgDbSrCVbr48/30zgu0VuC/FTA=
-github.com/bool64/dev v0.1.41/go.mod h1:cTHiTDNc8EewrQPy3p1obNilpMpdmlUesDkFTF2zRWU=
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/bool64/ctxd v1.2.1 h1:hARFteq0zdn4bwfmxLhak3fXFuvtJVKDH2X29VV/2ls=
+github.com/bool64/ctxd v1.2.1/go.mod h1:ZG6QkeGVLTiUl2mxPpyHmFhDzFZCyocr9hluBV3LYuc=
+github.com/bool64/dev v0.2.20/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/bool64/dev v0.2.24/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/bool64/dev v0.2.27 h1:mFT+B74mFVgUeUmm/EbfM6ELPA55lEXBjQ/AOHCwCOc=
+github.com/bool64/dev v0.2.27/go.mod h1:iJbh1y/HkunEPhgebWRNcs8wfGq7sjvJ6W5iabL8ACg=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
+github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
@@ -18,43 +21,58 @@ github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/swaggest/usecase v0.1.5 h1:xMDWXnYGysVaF2f3ZnmDsn2FlZ8fd3FJD+O+8wl4aNQ=
-github.com/swaggest/usecase v0.1.5/go.mod h1:uubX4ZbjQK1Bnl0xX9hOYpb/IUiSoVKk/yQImawbNMU=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/swaggest/usecase v1.2.0 h1:cHVFqxIbHfyTXp02JmWXk+ZADaSa87UZP+b3qL5Nz90=
+github.com/swaggest/usecase v1.2.0/go.mod h1:oc5+QoAxG3Et5Gl9lRXgEOm00l4VN9gdVQSMIa5EeLY=
 github.com/vearutop/dynhist-go v1.0.0 h1:SLYGcQMzmIoWnuqtF9lV8ULUBC735A56M5nL2CNth4c=
 github.com/vearutop/dynhist-go v1.0.0/go.mod h1:7Cgyu5Ww8FwdB+Y+zawRz9cQT5oXAxw294L9lQ+JI/k=
-go.uber.org/atomic v1.7.0 h1:ADUqmZGgLDDfbSL9ZmPxKTybcoEYHgpYfELNoN+7hsw=
-go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
-go.uber.org/goleak v1.1.10 h1:z+mqJhf6ss6BSfSM671tgKyZBFPTTJM+HLxnhPC3wu0=
-go.uber.org/goleak v1.1.10/go.mod h1:8a7PlsEVH3e/a/GLqe5IIrQx6GzcnRmZEufDUTk4A7A=
-go.uber.org/multierr v1.6.0 h1:y6IPFStTAIT5Ytl7/XYmHvzXQ7S3g/IeZW9hyZ5thw4=
-go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=
-go.uber.org/zap v1.19.0 h1:mZQZefskPPCMIBCSEH0v2/iUqqLrYtaeqwD6FUGUnFE=
-go.uber.org/zap v1.19.0/go.mod h1:xg/QME4nWcxGxrpdeYfq7UvYrLh66cuVKdrbD1XF/NI=
+github.com/vearutop/lograte v1.0.5 h1:H3XAhqjggYt0oyJ8AqzxHClKpJW0odmu3mYYMeLcvkQ=
+github.com/vearutop/lograte v1.0.5/go.mod h1:hN7Zo1dpCKPVEEkxPM3zKtZHpkxtOip0cSITUZKZAxg=
+go.uber.org/atomic v1.6.0 h1:Ezj3JGmsOnG1MoRWQkPBsKLe9DwWD9QeXzTRzzldNVk=
+go.uber.org/atomic v1.6.0/go.mod h1:sABNBOSYdrvTF6hTgEIbc7YasKWGhgEQZyfxyTvoXHQ=
+go.uber.org/multierr v1.5.0 h1:KCa4XfM8CWFCpxXRGok+Q0SS/0XBhMDbHHGABQLvD2A=
+go.uber.org/multierr v1.5.0/go.mod h1:FeouvMocqHpRaaGuG9EjoKcStLC43Zu/fmqdUMPcKYU=
+go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee h1:0mgffUl7nfd+FpvXMVz4IDEaUSmT1ysygQC7qYo7sG4=
+go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee/go.mod h1:vJERXedbb3MVM5f9Ejo0C68/HhF8uaILCdgjnY+goOA=
+go.uber.org/zap v1.16.0 h1:uFRZXykJGK9lLY4HtgSw44DnIcAM+kRBP7x5m+NpAOM=
+go.uber.org/zap v1.16.0/go.mod h1:MA8QOfq0BHJwdXa996Y4dYkAqRKB8/1K1QMMZVaNZjQ=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/lint v0.0.0-20190930215403-16217165b5de h1:5hukYrvBGR8/eNkX5mdUezrA6JiaEZDtJb9Ei+1LlBs=
 golang.org/x/lint v0.0.0-20190930215403-16217165b5de/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
+golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
-golang.org/x/tools v0.0.0-20191108193012-7d206e10da11 h1:Yq9t9jnGoR+dBuitxdo9l6Q7xh/zOyNnYUtDKaQ3x0E=
-golang.org/x/tools v0.0.0-20191108193012-7d206e10da11/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
+golang.org/x/tools v0.0.0-20191029041327-9cc4af7d6b2c/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20191029190741-b9c20aec41a5 h1:hKsoRgsbwY1NafxrwTs+k64bikrLBkAgPir1TNCj3Zs=
+golang.org/x/tools v0.0.0-20191029190741-b9c20aec41a5/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.5 h1:ymVxjfMaHvXD8RqPRmzHHsB3VvucivSkIAvJFDI5O3c=
 gopkg.in/yaml.v2 v2.2.5/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
-gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+honnef.co/go/tools v0.0.1-2019.2.3 h1:3JgtbtFHMiCmsznwGVTUWbgGov+pVqnlf1dEJTNAXeM=
+honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
diff --git a/logzpage/handler.go b/logzpage/handler.go
index 15e12fa..f40f0ae 100644
--- a/logzpage/handler.go
+++ b/logzpage/handler.go
@@ -23,7 +23,7 @@ type tplData struct {
 }
 
 // Handler creates HTTP handler to expose entries from observers.
-func Handler(observers ...*logz.Observer) http.Handler { // nolint:funlen // This template is lengthy.
+func Handler(observers ...*logz.Observer) http.Handler { //nolint:funlen // This template is lengthy.
 	// language=GoTemplate
 	tpl := `{{- /*gotype: github.com/bool64/logz/logzpage.tplData*/ -}}
 <!DOCTYPE html>
@@ -146,7 +146,7 @@ func Handler(observers ...*logz.Observer) http.Handler { // nolint:funlen // Thi
 	t, err := template.New("Logz").Funcs(template.FuncMap{
 		"marshal": marshal,
 		"histogram": func(buckets []logz.Bucket) template.HTML {
-			return template.HTML(Histogram(buckets)) // nolint:gosec // Data is well-formed.
+			return template.HTML(Histogram(buckets)) //nolint:gosec // Data is well-formed.
 		},
 		"time": func(t time.Time) string {
 			return t.Format(time.RFC3339)
@@ -207,7 +207,7 @@ func Handler(observers ...*logz.Observer) http.Handler { // nolint:funlen // Thi
 
 func marshal(v interface{}) template.JS {
 	if bb, ok := v.([]byte); ok {
-		return template.JS(bb) // nolint:gosec // Data is well-formed.
+		return template.JS(bb) //nolint:gosec // Data is well-formed.
 	}
 
 	b := bytes.Buffer{}
@@ -217,10 +217,10 @@ func marshal(v interface{}) template.JS {
 
 	err := enc.Encode(v)
 	if err != nil {
-		return template.JS(err.Error()) // nolint:gosec // Data is well-formed.
+		return template.JS(err.Error()) //nolint:gosec // Data is well-formed.
 	}
 
-	return template.JS(b.Bytes()) // nolint:gosec // Data is well-formed.
+	return template.JS(b.Bytes()) //nolint:gosec // Data is well-formed.
 }
 
 // Histogram renders distribution using HTML elements.
diff --git a/observer.go b/observer.go
index 2d642e1..45738bf 100644
--- a/observer.go
+++ b/observer.go
@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/vearutop/dynhist-go"
+	"github.com/vearutop/lograte/filter"
 )
 
 // Config defines observer configuration.
@@ -23,7 +24,7 @@ type Config struct {
 	// Default 10.
 	MaxSamples uint32
 
-	// SamplingInterval is the minimum amount of time needed to pass from a last sample collection in particular message family.
+	// SamplingInterval is the minimum amount of time needed to pass from a last Sample collection in particular message family.
 	// Messages that are observed too quickly after last sampling are counted, but not sampled.
 	// Default 1ms.
 	SamplingInterval time.Duration
@@ -35,6 +36,13 @@ type Config struct {
 	// DistRetentionPeriod is maximum age of bucket. Use -1 for unlimited.
 	// Default one week (168 hours).
 	DistRetentionPeriod time.Duration
+
+	// FilterMessage can reduce cardinality by filtering dynamic parts of messages.
+	// It uses github.com/vearutop/lograte/filter.Dynamic
+	// See https://pkg.go.dev/github.com/vearutop/lograte/filter#Dynamic.
+	// This option is not needed if you already have messages without dynamic interpolated values.
+	// This option worsen performance, so use it only if you need it.
+	FilterMessage bool
 }
 
 // Observer keeps track of messages.
@@ -54,7 +62,7 @@ type Observer struct {
 
 type entry struct {
 	msg                 string
-	samples             chan sample
+	samples             chan Sample
 	count               uint64
 	first               int64
 	latest              int64
@@ -62,13 +70,14 @@ type entry struct {
 	distRetentionPeriod int64
 }
 
-type sample struct {
+// Sample is a single sample of a message.
+type Sample struct {
 	Msg  string      `json:"msg"`
 	Data interface{} `json:"data"`
 	Time time.Time   `json:"time"`
 }
 
-func (en *entry) push(now int64, sample sample) {
+func (en *entry) push(now int64, sample Sample) {
 	cnt := atomic.AddUint64(&en.count, 1)
 
 	if en.distribution != nil {
@@ -89,7 +98,7 @@ func (en *entry) push(now int64, sample sample) {
 
 	atomic.StoreInt64(&en.latest, now)
 
-	// Push new sample.
+	// Push new Sample.
 	<-en.samples
 	en.samples <- sample
 }
@@ -121,10 +130,10 @@ func (l *Observer) initialize() {
 	}
 
 	l.other = &entry{
-		samples: make(chan sample, l.maxSamples),
+		samples: make(chan Sample, l.maxSamples),
 	}
 	for i := uint32(0); i < l.maxSamples; i++ {
-		l.other.samples <- sample{}
+		l.other.samples <- Sample{}
 	}
 
 	if l.distResolution > 0 {
@@ -141,12 +150,16 @@ func (l *Observer) ObserveMessage(msg string, data interface{}) {
 
 	tn := time.Now()
 	now := tn.UnixNano() / l.samplingInterval
-	s := sample{
+	s := Sample{
 		Msg:  msg,
 		Data: data,
 		Time: tn,
 	}
 
+	if l.Config.FilterMessage {
+		msg = string(filter.Dynamic([]byte(msg), 200))
+	}
+
 	if e, ok := l.entries.Load(msg); ok {
 		e.(*entry).push(now, s)
 
@@ -158,7 +171,7 @@ func (l *Observer) ObserveMessage(msg string, data interface{}) {
 			msg:     msg,
 			first:   now,
 			count:   0,
-			samples: make(chan sample, l.maxSamples),
+			samples: make(chan Sample, l.maxSamples),
 		}
 
 		if l.distResolution > 0 {
@@ -169,7 +182,7 @@ func (l *Observer) ObserveMessage(msg string, data interface{}) {
 		}
 
 		for i := uint32(0); i < l.maxSamples; i++ {
-			e.samples <- sample{}
+			e.samples <- Sample{}
 		}
 		l.entries.Store(msg, &e)
 		atomic.AddUint32(&l.count, 1)
@@ -208,7 +221,7 @@ func (l *Observer) exportEntry(en *entry, withSamples bool) Entry {
 	}
 
 	if withSamples {
-		e.Samples = make([]interface{}, 0, l.maxSamples)
+		e.Samples = make([]Sample, 0, l.maxSamples)
 
 		for i := int(l.maxSamples) - 1; i >= 0; i-- {
 			sample := <-en.samples
@@ -227,7 +240,7 @@ func (l *Observer) exportEntry(en *entry, withSamples bool) Entry {
 type Entry struct {
 	Message string
 	Count   uint64
-	Samples []interface{}
+	Samples []Sample
 	First   time.Time
 	Last    time.Time
 
diff --git a/observer_test.go b/observer_test.go
index 999c8b2..8ed34c7 100644
--- a/observer_test.go
+++ b/observer_test.go
@@ -42,6 +42,39 @@ func TestObserver_ObserveMessage(t *testing.T) {
 	assert.NotEmpty(t, entry.Samples)
 }
 
+func TestObserver_ObserveMessage_filter(t *testing.T) {
+	o := logz.Observer{}
+	o.Config.FilterMessage = true
+
+	o.ObserveMessage("test foo123", 123)
+	o.ObserveMessage("test bar456", 456)
+	o.ObserveMessage("another test", 789)
+
+	entries := o.GetEntries()
+
+	// Order of entries may be random as they are retrieved from a map.
+	sort.Slice(entries, func(i, j int) bool {
+		return entries[i].Message > entries[j].Message
+	})
+
+	assert.Equal(t, "test X", entries[0].Message)
+	assert.Equal(t, uint64(2), entries[0].Count)
+	assert.NotEmpty(t, entries[0].First)
+	assert.NotEmpty(t, entries[0].Last)
+
+	assert.Equal(t, "another test", entries[1].Message)
+	assert.Equal(t, uint64(1), entries[1].Count)
+	assert.NotEmpty(t, entries[1].First)
+	assert.NotEmpty(t, entries[1].Last)
+
+	entry := o.Find("test X")
+	assert.Equal(t, "test X", entry.Message)
+	assert.Equal(t, uint64(2), entry.Count)
+	assert.NotEmpty(t, entry.First)
+	assert.NotEmpty(t, entry.Last)
+	assert.NotEmpty(t, entry.Samples)
+}
+
 func BenchmarkObserver_ObserveMessage(b *testing.B) {
 	o := logz.Observer{}
 	wg := sync.WaitGroup{}
@@ -64,3 +97,27 @@ func BenchmarkObserver_ObserveMessage(b *testing.B) {
 
 	wg.Wait()
 }
+
+func BenchmarkObserver_ObserveMessage_filter(b *testing.B) {
+	o := logz.Observer{}
+	o.Config.FilterMessage = true
+	wg := sync.WaitGroup{}
+	concurrency := 50
+
+	b.ReportAllocs()
+
+	for i := 0; i < concurrency; i++ {
+		msg := "foo bar message" + strconv.Itoa(i)
+
+		wg.Add(1)
+
+		go func() {
+			for i := 0; i < b.N/concurrency; i++ {
+				o.ObserveMessage(msg, i)
+			}
+			wg.Done()
+		}()
+	}
+
+	wg.Wait()
+}