diff --git a/.gitignore b/.gitignore
index d86667f4..1aa8ebbb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,6 +8,7 @@
 *~
 .*.swo
 .*.swp
+.clj-kondo/
 .DS_Store
 .eastwood
 .idea/
diff --git a/project.clj b/project.clj
index 0f8f3cb8..331047b6 100644
--- a/project.clj
+++ b/project.clj
@@ -1,7 +1,7 @@
 ;; Please don't bump the library version by hand - use ci.release-workflow instead.
 (defproject formatting-stack "1.0.1"
   ;; Please keep the dependencies sorted a-z.
-  :dependencies [[clj-kondo "2019.05.19-alpha"]
+  :dependencies [[clj-kondo "2020.01.13"]
                  [cljfmt "0.6.5" :exclusions [rewrite-clj]]
                  [com.gfredericks/how-to-ns "0.2.6"]
                  [com.gfredericks/lein-all-my-files-should-end-with-exactly-one-newline-character "0.1.1"]
diff --git a/src/formatting_stack/branch_formatter.clj b/src/formatting_stack/branch_formatter.clj
index 62857d75..86b79374 100644
--- a/src/formatting_stack/branch_formatter.clj
+++ b/src/formatting_stack/branch_formatter.clj
@@ -59,7 +59,7 @@
                                 strategies/exclude-cljs
                                 strategies/jvm-requirable-files
                                 strategies/namespaces-within-refresh-dirs-only)))
-   (-> (linters.kondo/new)
+   (-> (linters.kondo/new {})
        (assoc :strategies (conj default-strategies
                                 strategies/exclude-edn
                                 strategies/exclude-clj
diff --git a/src/formatting_stack/core.clj b/src/formatting_stack/core.clj
index 21e5fa51..66c484e1 100644
--- a/src/formatting_stack/core.clj
+++ b/src/formatting_stack/core.clj
@@ -2,7 +2,7 @@
   (:require
    [clojure.main]
    [formatting-stack.background]
-   [formatting-stack.defaults :refer :all]
+   [formatting-stack.defaults :refer [default-processors default-formatters default-linters default-strategies]]
    [formatting-stack.indent-specs :refer [default-third-party-indent-specs]]
    [formatting-stack.protocols.formatter :as protocols.formatter]
    [formatting-stack.protocols.linter :as protocols.linter]
@@ -69,14 +69,9 @@
         in-background?           (if (some? in-background?)
                                    in-background?
                                    true)
-        {formatters-strategies
-         :formatters
-         linters-strategies
-         :linters
-         processors-strategies
-         :processors
-         default-strategies
-         :default}               strategies
+        {formatters-strategies :formatters
+         linters-strategies    :linters
+         processors-strategies :processors} strategies
         impl (bound-fn [] ;; important that it's a bound-fn (for an undetermined reason)
                (process! protocols.formatter/format! formatters formatters-strategies strategies intersperse-newlines?)
                (when intersperse-newlines?
diff --git a/src/formatting_stack/defaults.clj b/src/formatting_stack/defaults.clj
index 74ea9f7b..d45ec9e6 100644
--- a/src/formatting_stack/defaults.clj
+++ b/src/formatting_stack/defaults.clj
@@ -59,7 +59,7 @@
                                                    strategies/exclude-cljs
                                                    strategies/jvm-requirable-files
                                                    strategies/namespaces-within-refresh-dirs-only)))
-                      (-> (linters.kondo/new)
+                      (-> (linters.kondo/new {})
                           (assoc :strategies (conj extended-strategies
                                                    strategies/exclude-edn
                                                    strategies/exclude-clj
diff --git a/src/formatting_stack/formatters/clean_ns/impl.clj b/src/formatting_stack/formatters/clean_ns/impl.clj
index 67f85f86..05f4ebf6 100644
--- a/src/formatting_stack/formatters/clean_ns/impl.clj
+++ b/src/formatting_stack/formatters/clean_ns/impl.clj
@@ -4,11 +4,12 @@
    [clojure.tools.reader :as tools.reader]
    [clojure.tools.reader.reader-types :refer [push-back-reader]]
    [clojure.walk :as walk]
-   [formatting-stack.util :refer [ensure-coll rcomp try-require]]
+   [formatting-stack.util :refer [ensure-coll rcomp]]
    [nedap.speced.def :as speced]
    [refactor-nrepl.config]
    [refactor-nrepl.ns.clean-ns :refer [clean-ns]])
   (:import
+   (clojure.lang Namespace)
    (java.io File)))
 
 (speced/defn ns-form-of [^string? filename]
@@ -20,7 +21,7 @@
           nil
           (throw e))))))
 
-(speced/defn safely-read-ns-contents [^string? buffer, ^clojure.lang.Namespace ns-obj]
+(speced/defn safely-read-ns-contents [^string? buffer, ^Namespace ns-obj]
   (binding [tools.reader/*alias-map* (ns-aliases ns-obj)]
     (tools.reader/read-string {:read-cond :allow
                                :features  #{:clj}}
diff --git a/src/formatting_stack/formatters/cljfmt/impl.clj b/src/formatting_stack/formatters/cljfmt/impl.clj
index d67ee7c6..7b4a0678 100644
--- a/src/formatting_stack/formatters/cljfmt/impl.clj
+++ b/src/formatting_stack/formatters/cljfmt/impl.clj
@@ -23,7 +23,7 @@
     (locking require-lock
       (require namespace))
     (ns-map namespace)
-    (catch Exception e
+    (catch Exception _
       {})))
 
 (spec/def ::indent-key #{:style/indent :style.cljfmt/indent :style.cljfmt/type})
@@ -106,7 +106,7 @@
     (doseq [[sym var-ref] ns-mappings
             :when (var? var-ref)
             :let [fqn (fully-qualified-name-of var-ref)]
-            :when (some (fn [[k v]]
+            :when (some (fn [[k _]]
                           (= k fqn))
                         @result)
             :let [indent (get @result fqn)]]
diff --git a/src/formatting_stack/linters/kondo.clj b/src/formatting_stack/linters/kondo.clj
index 527a0355..f4ae7374 100644
--- a/src/formatting_stack/linters/kondo.clj
+++ b/src/formatting_stack/linters/kondo.clj
@@ -1,22 +1,50 @@
 (ns formatting-stack.linters.kondo
   (:require
-   [formatting-stack.linters.kondo.impl :as impl]
+   [clj-kondo.core :as clj-kondo]
    [formatting-stack.protocols.linter :as linter]
+   [medley.core :refer [deep-merge]]
    [nedap.utils.modular.api :refer [implement]]))
 
 (def off {:level :off})
 
 (def default-options
-  (list "--config" (pr-str {:linters {:invalid-arity     off
-                                      :cond-without-else off}})))
+  {:linters {:cond-else            off  ;; undesired
+             :missing-docstring    off  ;; undesired
+             :unused-symbol        off  ;; undesired because potentially unreliable
+             :unused-private-var   off  ;; undesired because potentially unreliable
+             :consistent-alias     off  ;; duped by how-to-ns
+             :duplicate-require    off  ;; duped by clean-ns
+             :unused-import        off  ;; duped by clean-ns
+             :unused-namespace     off  ;; duped by clean-ns
+             :unused-referred-var  off  ;; duped by clean-ns
+             :unresolved-namespace off} ;; duped by clean-ns
+   :lint-as '{nedap.speced.def/def-with-doc clojure.core/defonce
+              nedap.speced.def/defn         clojure.core/defn
+              nedap.speced.def/defprotocol  clojure.core/defprotocol
+              nedap.speced.def/doc          clojure.repl/doc
+              nedap.speced.def/fn           clojure.core/fn
+              nedap.speced.def/let          clojure.core/let
+              nedap.speced.def/letfn        clojure.core/letfn}
+   :output {:exclude-files ["test-resources/*"
+                            "test/unit/formatting_stack/formatters/cljfmt/impl/sample_data.clj"]}})
 
-(defn lint! [this filenames]
-  (->> filenames
-       (cons "--lint")
-       (concat default-options)
-       (impl/parse-opts)
-       impl/lint!))
+(def clj-options
+  "CLJ files are also linted by eastwood, disable duplicate linters"
+  {:linters {:misplaced-docstring  off
+             :deprecated-var       off
+             :redefined-var        off}})
 
-(defn new []
-  (implement {}
+(defn lint! [{:keys [kondo-options]} filenames]
+  (let [{cljs-files true
+         clj-files false} (group-by (fn [f] (boolean (re-find #"\.cljs$" f))) filenames)
+        findings (->> [(clj-kondo/run! {:lint clj-files
+                                        :config (deep-merge default-options clj-options (or kondo-options {}))})
+                       (clj-kondo/run! {:lint cljs-files
+                                        :config (deep-merge default-options (or kondo-options {}))})]
+                      (map :findings)
+                      (reduce into))]
+    (clj-kondo/print! {:findings findings})))
+
+(defn new [{:keys [kondo-options] :as options}]
+  (implement options
     linter/--lint! lint!))
diff --git a/src/formatting_stack/linters/kondo/impl.clj b/src/formatting_stack/linters/kondo/impl.clj
deleted file mode 100644
index a206c0d2..00000000
--- a/src/formatting_stack/linters/kondo/impl.clj
+++ /dev/null
@@ -1,292 +0,0 @@
-(ns formatting-stack.linters.kondo.impl
-  "Vendorized/forked copy of clj-kondo.main. https://github.com/borkdude/clj-kondo#license"
-  (:require
-   [clj-kondo.impl.analyzer :as ana]
-   [clj-kondo.impl.cache :as cache]
-   [clj-kondo.impl.config :as config]
-   [clj-kondo.impl.linters :as l]
-   [clj-kondo.impl.namespace :as namespace]
-   [clj-kondo.impl.overrides :refer [overrides]]
-   [clj-kondo.impl.profiler :as profiler]
-   [clj-kondo.impl.state :as state]
-   [clojure.edn :as edn]
-   [clojure.java.io :as io]
-   [clojure.string :as str :refer [ends-with? starts-with?]])
-  (:import
-   (java.util.jar JarFile JarFile$JarFileEntry)))
-
-(def dev? (= "true" (System/getenv "CLJ_KONDO_DEV")))
-
-(def ^:private version (str/trim
-                        (slurp (io/resource "CLJ_KONDO_VERSION"))))
-(set! *warn-on-reflection* true)
-
-(defn- format-output []
-  (if-let [^String pattern (-> @config/config :output :pattern)]
-    (fn [filename row col level message]
-      (-> pattern
-          (str/replace "{{filename}}" filename)
-          (str/replace "{{row}}" (str row))
-          (str/replace "{{col}}" (str col))
-          (str/replace "{{level}}" (name level))
-          (str/replace "{{LEVEL}}" (str/upper-case (name level)))
-          (str/replace "{{message}}" message)))
-    (fn [filename row col level message]
-      (str filename ":" row ":" col ": " (name level) ": " message))))
-
-(defn- print-findings [findings]
-  (let [format-fn (format-output)]
-    (doseq [{:keys [filename message level row col] :as finding}
-            (dedupe (sort-by (juxt :filename :row :col) findings))]
-      (println (format-fn filename row col level message)))))
-
-(defn- print-version []
-  (println (str "clj-kondo v" version)))
-
-(defn- print-help []
-  (print-version)
-  ;; TODO: document config format when stable enough
-  (println (format "
-Usage: [ --help ] [ --version ] [ --lint <files> ] [ --lang (clj|cljs) ] [ --cache [ <dir> ] ] [ --config <config> ]
-
-Options:
-
-  --lint: a file can either be a normal file, directory or classpath. In the
-    case of a directory or classpath, only .clj, .cljs and .cljc will be
-    processed. Use - as filename for reading from stdin.
-
-  --lang: if lang cannot be derived from the file extension this option will be
-    used.
-
-  --cache: if dir exists it is used to write and read data from, to enrich
-    analysis over multiple runs. If no value is provided, the nearest .clj-kondo
-    parent directory is detected and a cache directory will be created in it.
-
-  --config: config may be a file or an EDN expression. See
-    https://cljdoc.org/d/clj-kondo/clj-kondo/%s/doc/configuration.
-" version))
-  nil)
-
-(defn- source-file? [filename]
-  (or (ends-with? filename ".clj")
-      (ends-with? filename ".cljc")
-      (ends-with? filename ".cljs")))
-
-(defn- sources-from-jar
-  [^String jar-path]
-  (let [jar (JarFile. jar-path)
-        entries (enumeration-seq (.entries jar))
-        entries (filter (fn [^JarFile$JarFileEntry x]
-                          (let [nm (.getName x)]
-                            (source-file? nm))) entries)]
-    (map (fn [^JarFile$JarFileEntry entry]
-           {:filename (.getName entry)
-            :source   (slurp (.getInputStream jar entry))}) entries)))
-
-(defn- sources-from-dir
-  [dir]
-  (let [files (file-seq dir)]
-    (keep (fn [^java.io.File file]
-            (let [nm (.getPath file)
-                  can-read? (.canRead file)
-                  source? (source-file? nm)]
-              (cond
-                (and can-read? source?)
-                {:filename nm
-                 :source   (slurp file)}
-                (and (not can-read?) source?)
-                (do (println (str nm ":0:0:") "warning: can't read, check file permissions")
-                    nil)
-                :else nil)))
-          files)))
-
-(defn- lang-from-file [file default-language]
-  (cond (ends-with? file ".clj")
-        :clj
-        (ends-with? file ".cljc")
-        :cljc
-        (ends-with? file ".cljs")
-        :cljs
-        :else default-language))
-
-(def ^:private cp-sep (System/getProperty "path.separator"))
-
-(defn- classpath? [f]
-  (str/includes? f cp-sep))
-
-(defn- process-file [filename default-language]
-  (try
-    (let [file (io/file filename)]
-      (cond
-        (.exists file)
-        (if (.isFile file)
-          (if (ends-with? file ".jar")
-            ;; process jar file
-            (mapcat #(ana/analyze-input (:filename %) (:source %)
-                                        (lang-from-file (:filename %) default-language)
-                                        dev?)
-                    (sources-from-jar filename))
-            ;; assume normal source file
-            (ana/analyze-input filename (slurp filename)
-                               (lang-from-file filename default-language)
-                               dev?))
-          ;; assume directory
-          (mapcat #(ana/analyze-input (:filename %) (:source %)
-                                      (lang-from-file (:filename %) default-language)
-                                      dev?)
-                  (sources-from-dir file)))
-        (= "-" filename)
-        (ana/analyze-input "<stdin>" (slurp *in*) default-language dev?)
-        (classpath? filename)
-        (mapcat #(process-file % default-language)
-                (str/split filename
-                           (re-pattern cp-sep)))
-        :else
-        [{:findings [{:level    :warning
-                      :filename filename
-                      :col      0
-                      :row      0
-                      :message  "file does not exist"}]}]))
-    (catch Throwable e
-      (if dev? (throw e)
-          [{:findings [{:level    :warning
-                        :filename filename
-                        :col      0
-                        :row      0
-                        :message  "could not process file"}]}]))))
-
-(defn- process-files [files default-lang]
-  (mapcat #(process-file % default-lang) files))
-
-;;;; find cache/config dir
-
-(defn- config-dir
-  ([] (config-dir
-       (io/file
-        (System/getProperty "user.dir"))))
-  ([cwd]
-   (loop [dir (io/file cwd)]
-     (let [cfg-dir (io/file dir ".clj-kondo")]
-       (if (.exists cfg-dir)
-         (if (.isDirectory cfg-dir)
-           cfg-dir
-           (throw (Exception. (str cfg-dir " must be a directory"))))
-         (when-let [parent (.getParentFile dir)]
-           (recur parent)))))))
-
-(def ^:private
-  empty-cache-opt-warning
-  "WARNING: --cache option didn't specify directory, but no .clj-kondo directory found. Continuing without cache. See https://github.com/borkdude/clj-kondo/blob/master/README.md#project-setup.")
-
-(defn parse-opts [options]
-  (let [opts (loop [options options
-                    opts-map {}
-                    current-opt nil]
-               (if-let [opt (first options)]
-                 (if (starts-with? opt "--")
-                   (recur (rest options)
-                          (assoc opts-map opt [])
-                          opt)
-                   (recur (rest options)
-                          (update opts-map current-opt conj opt)
-                          current-opt))
-                 opts-map))
-        default-lang (case (first (get opts "--lang"))
-                       "clj"  :clj
-                       "cljs" :cljs
-                       "cljc" :cljc
-                       :clj)
-        cache-opt (get opts "--cache")
-        cfg-dir (config-dir)
-        cache-dir (when cache-opt
-                    (if-let [cd (first cache-opt)]
-                      (io/file cd version)
-                      (if cfg-dir (io/file cfg-dir ".cache" version)
-                          (do (println empty-cache-opt-warning)
-                              nil))))
-        files (get opts "--lint")
-        raw-config (first (get opts "--config"))
-        config-edn? (when raw-config
-                      (str/starts-with? raw-config "{"))
-        config-opt (and raw-config
-                        (if config-edn?
-                          (edn/read-string raw-config)
-                          (edn/read-string (slurp raw-config))))
-        config-edn (when cfg-dir
-                     (let [f (io/file cfg-dir "config.edn")]
-                       (when (.exists f)
-                         (edn/read-string (slurp f)))))]
-    {:opts         opts
-     :files        files
-     :cache-dir    cache-dir
-     :default-lang default-lang
-     :configs      [config-edn config-opt]}))
-
-(defn- mmerge
-  "Merges maps no deeper than two levels"
-  [a b]
-  (merge-with merge a b))
-
-(defn- index-defs-and-calls [defs-and-calls]
-  (reduce
-   (fn [acc {:keys [:calls :defs :used :lang] :as m}]
-     (-> acc
-         (update-in [lang :calls] (fn [prev-calls]
-                                    (merge-with into prev-calls calls)))
-         (update-in [lang :defs] mmerge defs)
-         (update-in [lang :used] into used)))
-   {:clj  {:calls {} :defs {} :used #{}}
-    :cljs {:calls {} :defs {} :used #{}}
-    :cljc {:calls {} :defs {} :used #{}}}
-   defs-and-calls))
-
-(def ^:private zinc (fnil inc 0))
-
-(defn- summarize [findings]
-  (reduce (fn [acc {:keys [:level]}]
-            (update acc level zinc))
-          {:error 0 :warning 0 :info 0}
-          findings))
-
-(defn- filter-findings [findings]
-  (let [print-debug? (:debug @config/config)
-        filter-output (not-empty (-> @config/config :output :include-files))
-        remove-output (not-empty (-> @config/config :output :exclude-files))]
-    (for [{:keys [:filename :level :type] :as f} findings
-          :let [level (or (when type (-> @config/config :linters type :level))
-                          level)]
-          :when (and level (not= :off level))
-          :when (if (= :debug type)
-                  print-debug?
-                  true)
-          :when (if filter-output
-                  (some (fn [pattern]
-                          (re-find (re-pattern pattern) filename))
-                        filter-output)
-                  true)
-          :when (not-any? (fn [pattern]
-                            (re-find (re-pattern pattern) filename))
-                          remove-output)]
-      (assoc f :level level))))
-
-(defn lint! [{:keys [opts files default-lang cache-dir configs]}]
-  (state/clear-findings!)
-  (reset! namespace/namespaces {})
-  (run! config/merge-config! configs)
-  (let [processed (process-files files default-lang)
-        idacs (-> processed
-                  index-defs-and-calls
-                  (cache/sync-cache cache-dir)
-                  overrides)
-        linted-calls (doall (l/lint-calls idacs))
-        _ (l/lint-unused-namespaces!)
-        all-findings (concat linted-calls (mapcat :findings processed)
-                             @state/findings)
-        all-findings (filter-findings all-findings)
-        {:keys [error warning]} (summarize all-findings)]
-    (when (-> @config/config :output :show-progress)
-      (println))
-    (print-findings all-findings)
-    (cond (pos? error)   3
-          (pos? warning) 2
-          :else          0)))
diff --git a/src/formatting_stack/processors/kondo.clj b/src/formatting_stack/processors/kondo.clj
new file mode 100644
index 00000000..f1e6f89d
--- /dev/null
+++ b/src/formatting_stack/processors/kondo.clj
@@ -0,0 +1,26 @@
+(ns formatting-stack.processors.kondo
+  "Creates cache for entire classpath to make better use of the project-wide analysis capabilities."
+  (:require
+   [clj-kondo.core :as clj-kondo]
+   [clojure.string :as str]
+   [formatting-stack.kondo :refer [initial-run?]]
+   [formatting-stack.protocols.processor :as processor]
+   [nedap.utils.modular.api :refer [implement]])
+  (:import
+   (java.io File)))
+
+(defn process! [_this files]
+  (let [cache-dir ".clj-kondo"]
+    (-> cache-dir File. .mkdirs)
+    (when-not @initial-run?
+      (reset! initial-run? true)
+      (clj-kondo/run! {:lint (-> (System/getProperty "java.class.path")
+                                 (str/split #"\:"))
+                       :cache-dir cache-dir}))
+    (clj-kondo/run! {:lint files
+                     :cache-dir cache-dir}))
+  nil)
+
+(defn new []
+  (implement {}
+    processor/--process! process!))
diff --git a/src/formatting_stack/processors/test_runner.clj b/src/formatting_stack/processors/test_runner.clj
index 728efbb0..7462e066 100644
--- a/src/formatting_stack/processors/test_runner.clj
+++ b/src/formatting_stack/processors/test_runner.clj
@@ -6,7 +6,7 @@
   and invokes `#'clojure.test/run-tests` out of that result."
   (:require
    [clojure.test]
-   [formatting-stack.processors.test-runner.impl :refer :all]
+   [formatting-stack.processors.test-runner.impl :refer [ns->sym testable-namespaces]]
    [formatting-stack.protocols.processor :as processor]
    [formatting-stack.strategies :refer [git-completely-staged git-diff-against-default-branch git-not-completely-staged]]
    [nedap.utils.modular.api :refer [implement]]))
diff --git a/src/formatting_stack/processors/test_runner/impl.clj b/src/formatting_stack/processors/test_runner/impl.clj
index c5057560..d4640c1a 100644
--- a/src/formatting_stack/processors/test_runner/impl.clj
+++ b/src/formatting_stack/processors/test_runner/impl.clj
@@ -23,8 +23,7 @@
   "Some projects have the naming convention of prefixing the last segment with `t-`
    to denote a testing namespace."
   [^Namespace n]
-  (let [s (str n)
-        segments (-> n str (string/split #"\."))
+  (let [segments (-> n str (string/split #"\."))
         first-segments (butlast segments)
         last-segment (->> segments last (str "t-"))]
     (->> [last-segment]
diff --git a/src/formatting_stack/project_formatter.clj b/src/formatting_stack/project_formatter.clj
index 7972e1c0..6f587728 100644
--- a/src/formatting_stack/project_formatter.clj
+++ b/src/formatting_stack/project_formatter.clj
@@ -60,7 +60,7 @@
                                 strategies/exclude-cljs
                                 strategies/jvm-requirable-files
                                 strategies/namespaces-within-refresh-dirs-only)))
-   (-> (linters.kondo/new)
+   (-> (linters.kondo/new {})
        (assoc :strategies (conj default-strategies
                                 strategies/exclude-edn
                                 strategies/exclude-clj
diff --git a/src/formatting_stack/strategies/impl.clj b/src/formatting_stack/strategies/impl.clj
index 60d821c4..f191dd1a 100644
--- a/src/formatting_stack/strategies/impl.clj
+++ b/src/formatting_stack/strategies/impl.clj
@@ -46,9 +46,9 @@
                  (-> decl parse/deps-from-ns-decl) ;; no exceptions thrown
                  true)
                true)))
-      (catch Exception e
+      (catch Exception _
         false)
-      (catch AssertionError e
+      (catch AssertionError _
         false))))
 
 (defn extract-clj-files [files]
diff --git a/test/functional/formatting_stack/formatters/clean_ns.clj b/test/functional/formatting_stack/formatters/clean_ns.clj
index 2ea31768..9bcd9b4e 100644
--- a/test/functional/formatting_stack/formatters/clean_ns.clj
+++ b/test/functional/formatting_stack/formatters/clean_ns.clj
@@ -52,7 +52,7 @@
   (is (seq (impl/used-namespace-names should-not-be-cleaned-2-f #{}))))
 
 (deftest clean-ns-form
-  (are [op filename ns-form libspec-whitelist namespaces-that-should-never-cleaned]
+  (are [op filename libspec-whitelist namespaces-that-should-never-cleaned]
        (let [cleaner (sut/make-cleaner formatting-stack.formatters.how-to-ns/default-how-to-ns-opts
                                        sut/default-nrepl-opts
                                        namespaces-that-should-never-cleaned
@@ -60,16 +60,16 @@
                                        filename)
              v (util.ns/replaceable-ns-form filename cleaner formatting-stack.formatters.how-to-ns/default-how-to-ns-opts)]
          (op v))
-    some? should-be-cleaned-f               should-be-cleaned               sut/default-libspec-whitelist #{}
-    nil?  should-be-cleaned-f               should-be-cleaned               sut/default-libspec-whitelist #{'functional.formatting-stack.formatters.clean-ns.should-be-cleaned}
-    some? "dev/user.clj"                    (ns-form-of "dev/user.clj")     sut/default-libspec-whitelist #{}
-    nil?  "dev/user.clj"                    (ns-form-of "dev/user.clj")     sut/default-libspec-whitelist sut/default-namespaces-that-should-never-cleaned
-    nil?  should-not-be-partially-cleaned-f should-not-be-partially-cleaned sut/default-libspec-whitelist #{}
-    nil?  should-not-be-cleaned-f           should-not-be-cleaned           sut/default-libspec-whitelist #{}
-    nil?  should-not-be-cleaned-2-f         should-not-be-cleaned-2         sut/default-libspec-whitelist #{}
-    nil?  should-not-be-cleaned-3-f         should-not-be-cleaned-3         sut/default-libspec-whitelist #{}
-    nil?  should-not-be-cleaned-4-f         should-not-be-cleaned-4         sut/default-libspec-whitelist #{}
-    nil?  should-not-be-cleaned-5-f         should-not-be-cleaned-5         sut/default-libspec-whitelist #{}
-    some? should-not-be-cleaned-3-f         should-not-be-cleaned-3         #{}                           #{}
-    some? should-not-be-cleaned-4-f         should-not-be-cleaned-4         #{}                           #{}
-    some? should-not-be-cleaned-5-f         should-not-be-cleaned-5         #{}                           #{}))
+    some? should-be-cleaned-f               sut/default-libspec-whitelist #{}
+    nil?  should-be-cleaned-f               sut/default-libspec-whitelist #{'functional.formatting-stack.formatters.clean-ns.should-be-cleaned}
+    some? "dev/user.clj"                    sut/default-libspec-whitelist #{}
+    nil?  "dev/user.clj"                    sut/default-libspec-whitelist sut/default-namespaces-that-should-never-cleaned
+    nil?  should-not-be-partially-cleaned-f sut/default-libspec-whitelist #{}
+    nil?  should-not-be-cleaned-f           sut/default-libspec-whitelist #{}
+    nil?  should-not-be-cleaned-2-f         sut/default-libspec-whitelist #{}
+    nil?  should-not-be-cleaned-3-f         sut/default-libspec-whitelist #{}
+    nil?  should-not-be-cleaned-4-f         sut/default-libspec-whitelist #{}
+    nil?  should-not-be-cleaned-5-f         sut/default-libspec-whitelist #{}
+    some? should-not-be-cleaned-3-f         #{}                           #{}
+    some? should-not-be-cleaned-4-f         #{}                           #{}
+    some? should-not-be-cleaned-5-f         #{}                           #{}))
diff --git a/test/unit/formatting_stack/formatters/trivial_ns_duplicates.clj b/test/unit/formatting_stack/formatters/trivial_ns_duplicates.clj
index 61d48590..9f168d4e 100644
--- a/test/unit/formatting_stack/formatters/trivial_ns_duplicates.clj
+++ b/test/unit/formatting_stack/formatters/trivial_ns_duplicates.clj
@@ -30,8 +30,10 @@
     '[[a :refer [b c]] [a :refer [b c d]]] '[[a :refer [b c d]]]))
 
 (deftest remove-exact-duplicates
-  (are [desc input expected] (= expected
-                                (sut/remove-exact-duplicates input))
+  (are [desc input expected] (testing desc
+                               (is (= expected
+                                      (sut/remove-exact-duplicates input)))
+                               true)
 
     "returns nil when there's nothing to fix"
     '(ns foo)
diff --git a/worker/formatting_stack/kondo.clj b/worker/formatting_stack/kondo.clj
new file mode 100644
index 00000000..a5bb2381
--- /dev/null
+++ b/worker/formatting_stack/kondo.clj
@@ -0,0 +1,5 @@
+(ns formatting-stack.kondo
+  "This file live in a distinct source-paths so it's not affected by the Reloaded workflow,
+  while developing formatting-stack itself.")
+
+(defonce initial-run? (atom false))