Events grouping

I am sending to sentry exactly this data:

{:server-name kwladyka-iMac.local, :level :error, :logger etingroup.logs, :extra nil, :message test error, :throwable #error {
 :cause Divide by zero
 [{:type java.lang.ArithmeticException
   :message Divide by zero
   :at [clojure.lang.Numbers divide 158]}]
 [[clojure.lang.Numbers divide 158]
  [clojure.lang.Numbers divide 3808]
  [etingroup.logs$eval1858 invokeStatic logs.clj 77]
  [etingroup.logs$eval1858 invoke logs.clj 76]
  [clojure.lang.Compiler eval 6978]
  [clojure.lang.Compiler load 7430]
  [etingroup.core$eval1854 invokeStatic form-init2504031895435136755.clj 1]
  [etingroup.core$eval1854 invoke form-init2504031895435136755.clj 1]
  [clojure.lang.Compiler eval 6978]
  [clojure.lang.Compiler eval 6941]
  [clojure.core$eval invokeStatic core.clj 3187]
  [clojure.core$eval invoke core.clj 3183]
  [clojure.main$repl$read_eval_print__9945$fn__9948 invoke main.clj 242]
  [clojure.main$repl$read_eval_print__9945 invoke main.clj 242]
  [clojure.main$repl$fn__9954 invoke main.clj 260]
  [clojure.main$repl invokeStatic main.clj 260]
  [clojure.main$repl doInvoke main.clj 176]
  [clojure.lang.RestFn invoke 1523]
  [$evaluate$fn__896 invoke interruptible_eval.clj 87]
  [clojure.lang.AFn applyToHelper 152]
  [clojure.lang.AFn applyTo 144]
  [clojure.core$apply invokeStatic core.clj 657]
  [clojure.core$with_bindings_STAR_ invokeStatic core.clj 1963]
  [clojure.core$with_bindings_STAR_ doInvoke core.clj 1963]
  [clojure.lang.RestFn invoke 425]
  [$evaluate invokeStatic interruptible_eval.clj 85]
  [$evaluate invoke interruptible_eval.clj 55]
  [$interruptible_eval$fn__941$fn__944 invoke interruptible_eval.clj 222]
  [$run_next$fn__936 invoke interruptible_eval.clj 190]
  [clojure.lang.AFn run 22]
  [java.util.concurrent.ThreadPoolExecutor runWorker 1142]
  [java.util.concurrent.ThreadPoolExecutor$Worker run 617]
  [java.lang.Thread run 745]]}}

using this library

In doc [there was a link, but as a new user forum doesn’t allow write it] i can read:

If a stacktrace or exception is involved in a report then grouping will only consider this information.

But after send it many i have each error as separated and each have 1 events. It should be grouped, shouldn’t be?

Because of it doesn’t work I consider use

What this sentence mean?

Additionally if you simply wish to append information, thus making the grouping slightly less aggressive, you can do that as well: Raven.captureException(ex, {fingerprint: ['{{ default }}', 'other', 'data']})

What this {{ default }} do?

Do i really have to use fingerprints to group it correctly?

I solved it with fingerprints for now, it works.