diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7f41c207..345fafa4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,12 +6,16 @@ For a list of breaking changes, check [here](#breaking-changes).
 
 Babashka proper:
 
+- Add `clojure.tools.logging` with `taoensso.timbre` as the default implementation
 - Passing form on Windows with question mark breaks evaluation [#889](https://github.com/babashka/babashka/issues/889)
 - `(read-line)` is buggy in REPL [#899](https://github.com/babashka/babashka/issues/899)
 - Add `java.io.FileInputStream`. This fixes compatibility with [replikativ/hasch](https://github.com/replikativ/hasch).
 - `babashka.tasks/clojure` with `:dir` option doesn't resolve deps in `:dir` [#914](https://github.com/babashka/babashka/issues/914)
 - Support `pprint/formatter-out` [#922](https://github.com/babashka/babashka/issues/922)
 - Support `pprint/cl-format` with `with-out-str` [#930](https://github.com/babashka/babashka/issues/930)
+- Compatibility with `org.clojure/data.json {:mvn/version "2.4.0}"`
+- Support passing `GITLIBS` via `:extra-env` in `clojure` to set git lib dir:
+  `(clojure {:extra-env {"GITLIBS" ".gitlib"}} ,,,) [#934](https://github.com/babashka/babashka/issues/934)`
 
 Deps.clj:
 
diff --git a/deps.edn b/deps.edn
index e68e04de..275b302e 100644
--- a/deps.edn
+++ b/deps.edn
@@ -37,7 +37,9 @@
         org.clojure/core.match {:mvn/version "1.0.0"}
         hiccup/hiccup {:mvn/version "2.0.0-alpha2"}
         rewrite-clj/rewrite-clj {:mvn/version "1.0.605-alpha"}
-        selmer/selmer {:mvn/version "1.12.40"}}
+        selmer/selmer {:mvn/version "1.12.40"}
+        com.taoensso/timbre {:mvn/version "5.1.2"}
+        org.clojure/tools.logging {:mvn/version "1.1.0"}}
  :aliases {:babashka/dev
            {:main-opts ["-m" "babashka.main"]}
            :profile
diff --git a/project.clj b/project.clj
index 72f22857..2b2c2787 100644
--- a/project.clj
+++ b/project.clj
@@ -23,7 +23,9 @@
                  [cheshire "5.10.0"]
                  [nrepl/bencode "1.1.0"]
                  [borkdude/sci.impl.reflector "0.0.1"]
-                 [org.clojure/test.check "1.1.0"]]
+                 [org.clojure/test.check "1.1.0"]
+                 [com.taoensso/timbre "5.1.2"]
+                 [org.clojure/tools.logging "1.1.0"]]
   :profiles {:feature/xml  {:source-paths ["feature-xml"]
                             :dependencies [[org.clojure/data.xml "0.2.0-alpha6"]]}
              :feature/yaml {:source-paths ["feature-yaml"]
diff --git a/src/babashka/impl/timbre.clj b/src/babashka/impl/timbre.clj
new file mode 100644
index 00000000..803cf80b
--- /dev/null
+++ b/src/babashka/impl/timbre.clj
@@ -0,0 +1,137 @@
+(ns babashka.impl.timbre
+  (:require [clojure.tools.logging]
+            [clojure.tools.logging.impl :as impl]
+            [sci.core :as sci]
+            [taoensso.encore :as enc :refer [have]]
+            [taoensso.timbre :as timbre]))
+
+;;;; timbre
+
+(def tns (sci/create-ns 'taoensso.timbre nil))
+
+(defn- fline [and-form] (:line (meta and-form)))
+
+(defmacro log! ; Public wrapper around `-log!`
+  "Core low-level log macro. Useful for tooling, etc.
+    * `level`    - must eval to a valid logging level
+    * `msg-type` - must eval to e/o #{:p :f nil}
+    * `opts`     - ks e/o #{:config :?err :?ns-str :?file :?line :?base-data :spying?}
+  Supports compile-time elision when compile-time const vals
+  provided for `level` and/or `?ns-str`."
+  [level msg-type args & [opts]]
+  (have [:or nil? sequential?] args) ; To allow -> (delay [~@args])
+  (let [{:keys [?ns-str] :or {?ns-str (str @sci/ns)}} opts]
+    ;; level, ns may/not be compile-time consts:
+    (when-not (timbre/-elide? level ?ns-str)
+      (let [{:keys [config ?err ?file ?line ?base-data spying?]
+             :or   {config 'taoensso.timbre/*config*
+                    ?err   :auto ; => Extract as err-type v0
+                    ?file  @sci/file
+                    ;; NB waiting on CLJ-865:
+                    ?line (fline &form)}} opts
+
+            ?file (when (not= ?file "NO_SOURCE_PATH") ?file)
+
+            ;; Identifies this particular macro expansion; note that this'll
+            ;; be fixed for any fns wrapping `log!` (notably `tools.logging`,
+            ;; `slf4j-timbre`, etc.):
+            callsite-id
+            (hash [level msg-type args ; Unevaluated args (arg forms)
+                   ?ns-str ?file ?line (rand)])]
+
+        `(taoensso.timbre/-log! ~config ~level ~?ns-str ~?file ~?line ~msg-type ~?err
+                                (delay [~@args]) ~?base-data ~callsite-id ~spying?)))))
+
+(defn make-ns [ns sci-ns ks]
+  (reduce (fn [ns-map [var-name var]]
+            (let [m (meta var)
+                  no-doc (:no-doc m)
+                  doc (:doc m)
+                  arglists (:arglists m)]
+              (if no-doc ns-map
+                  (assoc ns-map var-name
+                         (sci/new-var (symbol var-name) @var
+                                      (cond-> {:ns sci-ns
+                                               :name (:name m)}
+                                        (:macro m) (assoc :macro true)
+                                        doc (assoc :doc doc)
+                                        arglists (assoc :arglists arglists)))))))
+          {}
+          (select-keys (ns-publics ns) ks)))
+
+(def config (sci/new-dynamic-var '*config* timbre/*config* {:ns tns}))
+
+(defn swap-config! [f & args]
+  (apply sci/alter-var-root config f args))
+
+(defn set-level! [level] (swap-config! (fn [m] (assoc m :min-level level))))
+
+(def timbre-namespace
+  (assoc (make-ns 'taoensso.timbre tns ['trace 'tracef 'debug 'debugf
+                                        'info 'infof 'warn 'warnf
+                                        'error 'errorf
+                                        '-log! 'with-level
+                                        'println-appender 'spit-appender])
+         'log! (sci/copy-var log! tns)
+         '*config* config
+         'swap-config! (sci/copy-var swap-config! tns)
+         'set-level! (sci/copy-var set-level! tns)))
+
+;;;; clojure.tools.logging
+
+(defn- force-var "To support dynamic vars, etc."
+  [x] (if (instance? clojure.lang.IDeref x) (deref x) x))
+
+(deftype Logger [logger-ns-str timbre-config]
+  clojure.tools.logging.impl/Logger
+
+  (enabled? [_ level]
+    ;; No support for per-call config
+    (timbre/may-log? level logger-ns-str
+                     (force-var timbre-config)))
+
+  (write! [_ level throwable message]
+    (log! level :p
+          [message] ; No support for pre-msg raw args
+          {:config  (force-var timbre-config) ; No support for per-call config
+           :?ns-str logger-ns-str
+           :?file   nil ; No support
+           :?line   nil ; ''
+           :?err    throwable})))
+
+(deftype LoggerFactory [get-logger-fn]
+  clojure.tools.logging.impl/LoggerFactory
+  (name [_] "Timbre")
+  (get-logger [_ logger-ns] (get-logger-fn logger-ns)))
+
+(alter-var-root
+ #'clojure.tools.logging/*logger-factory*
+ (fn [_]
+   (LoggerFactory.
+    (enc/memoize (fn [logger-ns] (Logger. (str logger-ns) config))))))
+
+(def lns (sci/create-ns 'clojure.tools.logging nil))
+
+(defmacro log
+  "Evaluates and logs a message only if the specified level is enabled. See log*
+  for more details."
+  ([level message]
+   `(clojure.tools.logging/log ~level nil ~message))
+  ([level throwable message]
+   `(clojure.tools.logging/log ~(deref sci/ns) ~level ~throwable ~message))
+  ([logger-ns level throwable message]
+   `(clojure.tools.logging/log clojure.tools.logging/*logger-factory* ~logger-ns ~level ~throwable ~message))
+  ([logger-factory logger-ns level throwable message]
+   `(let [logger# (impl/get-logger ~logger-factory ~logger-ns)]
+      (if (impl/enabled? logger# ~level)
+        (clojure.tools.logging/log* logger# ~level ~throwable ~message)))))
+
+(def tools-logging-namespace
+  (assoc (make-ns 'clojure.tools.logging lns ['debug 'debugf 'info 'infof 'warn 'warnf 'error 'errorf
+                                              'logp 'logf '*logger-factory* 'log*])
+         'log (sci/copy-var log lns)))
+
+(def lins (sci/create-ns 'clojure.tools.logging.impl nil))
+
+(def tools-logging-impl-namespace
+  (make-ns 'clojure.tools.logging.impl lins ['get-logger 'enabled?]))
diff --git a/src/babashka/main.clj b/src/babashka/main.clj
index b96ae97c..30cd7a77 100644
--- a/src/babashka/main.clj
+++ b/src/babashka/main.clj
@@ -33,6 +33,8 @@
    [babashka.impl.socket-repl :as socket-repl]
    [babashka.impl.tasks :as tasks :refer [tasks-namespace]]
    [babashka.impl.test :as t]
+   [babashka.impl.timbre :refer [timbre-namespace tools-logging-namespace
+                                 tools-logging-impl-namespace]]
    [babashka.impl.tools.cli :refer [tools-cli-namespace]]
    [babashka.nrepl.server :as nrepl-server]
    [babashka.wait :as wait]
@@ -350,7 +352,10 @@ Use bb run --help to show this help output.
        'babashka.process process-namespace
        'clojure.core.server clojure-core-server
        'babashka.deps deps-namespace
-       'babashka.tasks tasks-namespace}
+       'babashka.tasks tasks-namespace
+       'taoensso.timbre timbre-namespace
+       'clojure.tools.logging tools-logging-namespace
+       'clojure.tools.logging.impl tools-logging-impl-namespace}
     features/xml?  (assoc 'clojure.data.xml @(resolve 'babashka.impl.xml/xml-namespace))
     features/yaml? (assoc 'clj-yaml.core @(resolve 'babashka.impl.yaml/yaml-namespace)
                           'flatland.ordered.map @(resolve 'babashka.impl.ordered/ordered-map-ns))