ci: replace Maven Checkstyle with Flint

.github/renovate-tracked-deps.json

@@ -163,6 +163,7 @@
         "aqua:jonwiggins/xmloxide",
         "aqua:owenlamont/ryl",
         "biome",
+        "checkstyle",
         "editorconfig-checker",
         "google-java-format",
         "hugo",

.github/workflows/acceptance-tests.yml

@@ -15,7 +15,7 @@ jobs:
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Run acceptance tests
         run: mise run acceptance-test

.github/workflows/api-diff.yml

@@ -34,8 +34,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/build.yml

@@ -14,8 +14,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/bump-api-diff-baseline.yml

@@ -35,8 +35,8 @@ jobs:
           persist-credentials: true
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/generate-protobuf.yml

@@ -20,8 +20,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/github-pages.yaml

@@ -39,8 +39,8 @@ jobs:
           fetch-depth: 0
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
           cache: "false"
       - name: Setup Pages
         id: pages

.github/workflows/java-version-matrix-tests.yml

@@ -33,8 +33,8 @@ jobs:
       - name: Set up mise
         uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
 
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0

.github/workflows/jmx-exporter-compatibility.yml

@@ -24,8 +24,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
           working_directory: .mise/envs/jmx-exporter
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0

.github/workflows/lint.yml

@@ -23,8 +23,8 @@ jobs:
       - name: Setup mise
         uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
 
       - name: Lint
         env:

.github/workflows/micrometer-compatibility.yml

@@ -32,8 +32,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
           working_directory: .mise/envs/micrometer
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0

.github/workflows/native-tests.yml

@@ -15,8 +15,8 @@ jobs:
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
           working_directory: .mise/envs/native
       - name: Run native tests
         working-directory: .mise/envs/native

.github/workflows/nightly-benchmarks.yml

@@ -36,8 +36,8 @@ jobs:
       - name: Setup mise
         uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
 
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0

.github/workflows/pr-benchmarks.yml

@@ -47,8 +47,8 @@ jobs:
       - name: Setup mise
         uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
 
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0

.github/workflows/regenerate-api-diff-otel.yml

@@ -20,8 +20,8 @@ jobs:
           persist-credentials: false
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

.github/workflows/release.yml

@@ -71,8 +71,8 @@ jobs:
 
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
           cache: false
 
       - name: Build release version

.github/workflows/test-release-build.yml

@@ -20,8 +20,8 @@ jobs:
           fetch-depth: 0
       - uses: jdx/mise-action@9e7f7633ff6f6d6048a9418a68d48f288f50eb14 # v4.2.3
         with:
-          version: v2026.7.5
-          sha256: 5f7ab76afdf0780d12edeaa67e908094e9ccf7924cfe203e415c1cfb87bbf778
+          version: v2026.7.15
+          sha256: 9a729bbe121135da0c717d86d3328f21de5efcc6fa27ac8487ef481e428008d3
       - name: Cache local Maven repository
         uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
         with:

AGENTS.md

@@ -15,23 +15,23 @@ mise run ci
 # Quick compile without tests or checks (fastest)
 mise run compile
 
-# Run unit tests only (skips formatting/coverage/checkstyle)
+# Run unit tests only (skips formatting and coverage)
 mise run test
 
 # Run all tests including integration tests
 mise run test-all
 
 # Run a single test class
 ./mvnw test -Dtest=CounterTest \
-  -Dcoverage.skip=true -Dcheckstyle.skip=true
+  -Dcoverage.skip=true
 
 # Run a single test method
 ./mvnw test -Dtest=CounterTest#testIncrement \
-  -Dcoverage.skip=true -Dcheckstyle.skip=true
+  -Dcoverage.skip=true
 
 # Run tests in a specific module
 ./mvnw test -pl prometheus-metrics-core \
-  -Dcoverage.skip=true -Dcheckstyle.skip=true
+  -Dcoverage.skip=true
 
 # Regenerate protobuf classes (after protobuf dep update)
 mise run generate

CONTRIBUTING.md

@@ -89,14 +89,12 @@ mise --cd .mise/envs/native run native-test
 ### Avoid failures while running tests
 
 - Use `-Dcoverage.skip=true` to skip the coverage check during development.
-- Use `-Dcheckstyle.skip=true` to skip the checkstyle check during development.
 - Use `-Dwarnings=-nowarn` to skip the warnings during development.
 
 Combine all with
 
 ```shell
-./mvnw install -DskipTests -Dcoverage.skip=true \
-  -Dcheckstyle.skip=true -Dwarnings=-nowarn
+./mvnw install -DskipTests -Dcoverage.skip=true -Dwarnings=-nowarn
 ```
 
 or simply

checkstyle-suppressions.xml

@@ -21,4 +21,12 @@
 
   <!-- Suppress all Javadoc checks for integration tests -->
   <suppress checks="Javadoc" files=".*[/\\]integration-tests[/\\].*"/>
+
+  <!-- Preserve the repository's main-source-only Checkstyle policy when Flint invokes the
+       standalone CLI with explicit Java files. -->
+  <suppress checks=".*" files=".*[/\\]src[/\\]test[/\\]java[/\\].*"/>
+  <suppress checks=".*" files=".*[/\\]src[/\\]archive[/\\]java[/\\].*"/>
+
+  <!-- Example setup intentionally groups declarations before the simulated work that uses them. -->
+  <suppress checks="VariableDeclarationUsageDistance" files=".*[/\\]examples[/\\].*"/>
 </suppressions>