diff --git a/spec/compiler/crystal/tools/playground_spec.cr b/spec/compiler/crystal/tools/playground_spec.cr
index dcff25b7e7ae..2e122ab8912c 100644
--- a/spec/compiler/crystal/tools/playground_spec.cr
+++ b/spec/compiler/crystal/tools/playground_spec.cr
@@ -576,7 +576,7 @@ describe Playground::AgentInstrumentorTransformer do
 end
 
 private def assert_compile(source)
-  sources = Playground::Session.instrument_and_prelude("", "", 0, source, Logger.new(nil))
+  sources = Playground::Session.instrument_and_prelude("", "", 0, source)
   compiler = Compiler.new
   compiler.no_codegen = true
   result = compiler.compile sources, "fake-no-build"
diff --git a/spec/std/logger_spec.cr b/spec/std/logger_spec.cr
deleted file mode 100644
index d0b147032cb9..000000000000
--- a/spec/std/logger_spec.cr
+++ /dev/null
@@ -1,96 +0,0 @@
-require "spec"
-require "logger"
-
-describe "Logger" do
-  it "logs messages" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.debug "debug:skip"
-      logger.info "info:show"
-
-      logger.level = Logger::DEBUG
-      logger.debug "debug:show"
-
-      logger.level = Logger::WARN
-      logger.debug "debug:skip:again"
-      logger.info "info:skip"
-      logger.error "error:show"
-
-      r.gets.should match(/info:show/)
-      r.gets.should match(/debug:show/)
-      r.gets.should match(/error:show/)
-    end
-  end
-
-  it "logs any object" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.info 12345
-
-      r.gets.should match(/12345/)
-    end
-  end
-
-  it "formats message" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.progname = "crystal"
-      logger.warn "message"
-
-      r.gets(chomp: false).should match(/W, \[.+? #\d+\]  WARN -- crystal: message\n/)
-    end
-  end
-
-  it "uses custom formatter" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.formatter = Logger::Formatter.new do |severity, datetime, progname, message, io|
-        io << severity.to_s[0] << ' ' << progname << ": " << message
-      end
-      logger.warn "message", "prog"
-
-      r.gets(chomp: false).should eq("W prog: message\n")
-    end
-  end
-
-  it "yields message" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.error { "message" }
-      logger.unknown { "another message" }
-
-      r.gets(chomp: false).should match(/ERROR -- : message\n/)
-      r.gets(chomp: false).should match(/  ANY -- : another message\n/)
-    end
-  end
-
-  it "yields message with progname" do
-    IO.pipe do |r, w|
-      logger = Logger.new(w)
-      logger.error("crystal") { "message" }
-      logger.unknown("shard") { "another message" }
-
-      r.gets(chomp: false).should match(/ERROR -- crystal: message\n/)
-      r.gets(chomp: false).should match(/  ANY -- shard: another message\n/)
-    end
-  end
-
-  it "can create a logger with nil (#3065)" do
-    logger = Logger.new(nil)
-    logger.error("ouch")
-  end
-
-  it "doesn't yield to the block with nil" do
-    a = 0
-    logger = Logger.new(nil)
-    logger.info { a = 1 }
-    a.should eq(0)
-  end
-
-  it "closes" do
-    IO.pipe do |r, w|
-      Logger.new(w).close
-      w.closed?.should be_true
-    end
-  end
-end
diff --git a/src/compiler/crystal/command/playground.cr b/src/compiler/crystal/command/playground.cr
index 9fb76acb59c5..3a4cd974e760 100644
--- a/src/compiler/crystal/command/playground.cr
+++ b/src/compiler/crystal/command/playground.cr
@@ -2,6 +2,7 @@
 #
 # This is just the command-line part. The playground is
 # implemented in `crystal/tools/playground/`
+require "logger"
 
 class Crystal::Command
   private def playground
@@ -19,7 +20,7 @@ class Crystal::Command
       end
 
       opts.on("-v", "--verbose", "Display detailed information of executed code") do
-        server.logger.level = Logger::Severity::DEBUG
+        Logger.default_dispatcher.filter = Logger::DEBUG
       end
 
       opts.on("-h", "--help", "Show this message") do
diff --git a/src/compiler/crystal/tools/playground/server.cr b/src/compiler/crystal/tools/playground/server.cr
index 460c1ec19ed5..63885a05bb64 100644
--- a/src/compiler/crystal/tools/playground/server.cr
+++ b/src/compiler/crystal/tools/playground/server.cr
@@ -8,16 +8,18 @@ module Crystal::Playground
   class Session
     getter tag : Int32
 
-    def initialize(@ws : HTTP::WebSocket, @session_key : Int32, @port : Int32, @logger : Logger)
+    @@logger = Logger.get(self)
+
+    def initialize(@ws : HTTP::WebSocket, @session_key : Int32, @port : Int32)
       @running_process_filename = ""
       @tag = 0
     end
 
-    def self.instrument_and_prelude(session_key, port, tag, source, logger)
+    def self.instrument_and_prelude(session_key, port, tag, source)
       ast = Parser.new(source).parse
 
       instrumented = Playground::AgentInstrumentorTransformer.transform(ast).to_s
-      logger.info "Code instrumentation (session=#{session_key}, tag=#{tag}).\n#{instrumented}"
+      @@logger.info "Code instrumentation (session=#{session_key}, tag=#{tag}).\n#{instrumented}"
 
       prelude = %(
         require "compiler/crystal/tools/playground/agent"
@@ -42,11 +44,11 @@ module Crystal::Playground
     end
 
     def run(source, tag)
-      @logger.info "Request to run code (session=#{@session_key}, tag=#{tag}).\n#{source}"
+      @@logger.info "Request to run code (session=#{@session_key}, tag=#{tag}).\n#{source}"
 
       @tag = tag
       begin
-        sources = self.class.instrument_and_prelude(@session_key, @port, tag, source, @logger)
+        sources = self.class.instrument_and_prelude(@session_key, @port, tag, source)
       rescue ex : Crystal::Exception
         send_exception ex, tag
         return
@@ -56,22 +58,22 @@ module Crystal::Playground
       compiler = Compiler.new
       compiler.color = false
       begin
-        @logger.info "Instrumented code compilation started (session=#{@session_key}, tag=#{tag})."
+        @@logger.info "Instrumented code compilation started (session=#{@session_key}, tag=#{tag})."
         result = compiler.compile sources, output_filename
       rescue ex
-        @logger.info "Instrumented code compilation failed (session=#{@session_key}, tag=#{tag})."
+        @@logger.info "Instrumented code compilation failed (session=#{@session_key}, tag=#{tag})."
 
         # due to instrumentation, we compile the original program
         begin
-          @logger.info "Original code compilation started (session=#{@session_key}, tag=#{tag})."
+          @@logger.info "Original code compilation started (session=#{@session_key}, tag=#{tag})."
           compiler.compile Compiler::Source.new("play", source), output_filename
         rescue ex
-          @logger.info "Original code compilation failed (session=#{@session_key}, tag=#{tag})."
+          @@logger.info "Original code compilation failed (session=#{@session_key}, tag=#{tag})."
           send_exception ex, tag
           return # if we don't exit here we've found a bug
         end
 
-        @logger.error "Instrumention bug found (session=#{@session_key}, tag=#{tag})."
+        @@logger.error "Instrumention bug found (session=#{@session_key}, tag=#{tag})."
         send_with_json_builder do |json|
           json.field "type", "bug"
           json.field "tag", tag
@@ -93,7 +95,7 @@ module Crystal::Playground
     end
 
     def format(source, tag)
-      @logger.info "Request to format code (session=#{@session_key}, tag=#{tag}).\n#{source}"
+      @@logger.info "Request to format code (session=#{@session_key}, tag=#{tag}).\n#{source}"
 
       @tag = tag
 
@@ -119,7 +121,7 @@ module Crystal::Playground
       begin
         @ws.send(message)
       rescue ex : IO::Error
-        @logger.warn "Unable to send message (session=#{@session_key})."
+        @@logger.warn "Unable to send message (session=#{@session_key})."
       end
     end
 
@@ -158,7 +160,7 @@ module Crystal::Playground
 
     private def stop_process
       if process = @process
-        @logger.info "Code execution killed (session=#{@session_key}, filename=#{@running_process_filename})."
+        @@logger.info "Code execution killed (session=#{@session_key}, filename=#{@running_process_filename})."
         @process = nil
         File.delete @running_process_filename rescue nil
         process.kill rescue nil
@@ -168,13 +170,13 @@ module Crystal::Playground
     private def execute(tag, output_filename)
       stop_process
 
-      @logger.info "Code execution started (session=#{@session_key}, tag=#{tag}, filename=#{output_filename})."
+      @@logger.info "Code execution started (session=#{@session_key}, tag=#{tag}, filename=#{output_filename})."
       process = @process = Process.new(output_filename, args: [] of String, input: Process::Redirect::Pipe, output: Process::Redirect::Pipe, error: Process::Redirect::Pipe)
       @running_process_filename = output_filename
 
       spawn do
         status = process.wait
-        @logger.info "Code execution ended (session=#{@session_key}, tag=#{tag}, filename=#{output_filename})."
+        @@logger.info "Code execution ended (session=#{@session_key}, tag=#{tag}, filename=#{output_filename})."
         exit_status = status.normal_exit? ? status.exit_code : status.exit_signal.value
 
         send_with_json_builder do |json|
@@ -450,17 +452,16 @@ module Crystal::Playground
     @sessions = {} of Int32 => Session
     @sessions_key = 0
 
+    @@logger = Logger.get(self)
+
     property host : String?
     property port
-    property logger
     property source : Compiler::Source?
 
     def initialize
       @host = nil
       @port = 8080
       @verbose = false
-      @logger = Logger.new(STDOUT)
-      @logger.level = Logger::Severity::WARN
     end
 
     def start
@@ -472,7 +473,7 @@ module Crystal::Playground
         match_data = context.request.path.not_nil!.match(/\/(\d+)\/(\d+)$/).not_nil!
         session_key = match_data[1]?.try(&.to_i)
         tag = match_data[2]?.try(&.to_i)
-        @logger.info "#{context.request.path} WebSocket connected (session=#{session_key}, tag=#{tag})"
+        @@logger.info "#{context.request.path} WebSocket connected (session=#{session_key}, tag=#{tag})"
 
         session = @sessions[session_key]
 
@@ -488,12 +489,12 @@ module Crystal::Playground
       client_ws = PathWebSocketHandler.new "/client" do |ws, context|
         origin = context.request.headers["Origin"]
         if !accept_request?(origin)
-          @logger.warn "Invalid Request Origin: #{origin}"
+          @@logger.warn "Invalid Request Origin: #{origin}"
           ws.close "Invalid Request Origin"
         else
           @sessions_key += 1
-          @sessions[@sessions_key] = session = Session.new(ws, @sessions_key, @port, @logger)
-          @logger.info "/client WebSocket connected as session=#{@sessions_key}"
+          @sessions[@sessions_key] = session = Session.new(ws, @sessions_key, @port)
+          @@logger.info "/client WebSocket connected as session=#{@sessions_key}"
 
           ws.on_message do |message|
             json = JSON.parse(message)
diff --git a/src/logger.cr b/src/logger.cr
index 28103b89f9ee..b470c1e1b22f 100644
--- a/src/logger.cr
+++ b/src/logger.cr
@@ -1,178 +1,27 @@
-# The `Logger` class provides a simple but sophisticated logging utility that you can use to output messages.
-#
-# The messages have associated levels, such as `INFO` or `ERROR` that indicate their importance.
-# You can then give the `Logger` a level, and only messages at that level of higher will be printed.
-#
-# For instance, in a production system, you may have your `Logger` set to `INFO` or even `WARN`.
-# When you are developing the system, however, you probably want to know about the program’s internal state,
-# and would set the `Logger` to `DEBUG`.
-#
-# If logging to multiple locations is required, an `IO::MultiWriter` can be
-# used.
-#
-# ### Example
-#
-# ```
-# require "logger"
-#
-# log = Logger.new(STDOUT)
-# log.level = Logger::WARN
-#
-# # or
-# log = Logger.new(STDOUT, level: Logger::WARN)
-#
-# log.debug("Created logger")
-# log.info("Program started")
-# log.warn("Nothing to do!")
-#
-# begin
-#   File.each_line("/foo/bar.log") do |line|
-#     unless line =~ /^(\w+) = (.*)$/
-#       log.error("Line in wrong format: #{line}")
-#     end
-#   end
-# rescue err
-#   log.fatal("Caught exception; exiting")
-#   log.fatal(err)
-# end
-# ```
-class Logger
-  property level : Severity
-  property progname : String
-
-  # Customizable `Proc` (with a reasonable default)
-  # which the `Logger` uses to format and print its entries.
-  #
-  # Use this setter to provide a custom formatter.
-  # The `Logger` will invoke it with the following arguments:
-  #  - severity: a `Logger::Severity`
-  #  - datetime: `Time`, the entry's timestamp
-  #  - progname: `String`, the program name, if set when the logger was built
-  #  - message: `String`, the body of a message
-  #  - io: `IO`, the Logger's stream, to which you must write the final output
-  #
-  # Example:
-  #
-  # ```
-  # require "logger"
-  #
-  # logger = Logger.new(STDOUT)
-  # logger.progname = "YodaBot"
-  #
-  # logger.formatter = Logger::Formatter.new do |severity, datetime, progname, message, io|
-  #   label = severity.unknown? ? "ANY" : severity.to_s
-  #   io << label[0] << ", [" << datetime << " #" << Process.pid << "] "
-  #   io << label.rjust(5) << " -- " << progname << ": " << message
-  # end
-  #
-  # logger.warn("Fear leads to anger. Anger leads to hate. Hate leads to suffering.")
-  #
-  # # Prints to the console:
-  # # "W, [2017-05-06 18:00:41 -0300 #11927]  WARN --
-  # #  YodaBot: Fear leads to anger. Anger leads to hate. Hate leads to suffering."
-  # ```
-  property formatter
-
-  # A logger severity level.
-  enum Severity
-    # Low-level information for developers
-    DEBUG
-
-    # Generic (useful) information about system operation
-    INFO
-
-    # A warning
-    WARN
-
-    # A handleable error condition
-    ERROR
-
-    # An unhandleable error that results in a program crash
-    FATAL
-
-    UNKNOWN
-  end
-
-  alias Formatter = Severity, Time, String, String, IO ->
-
-  private DEFAULT_FORMATTER = Formatter.new do |severity, datetime, progname, message, io|
-    label = severity.unknown? ? "ANY" : severity.to_s
-    io << label[0] << ", [" << datetime << " #" << Process.pid << "] "
-    io << label.rjust(5) << " -- " << progname << ": " << message
-  end
-
-  # :nodoc:
-  record Message,
-    severity : Severity,
-    datetime : Time,
-    progname : String,
-    message : String
+require "logger/*"
+
+struct Logger
+  getter component : String
+  getter dispatcher : Dispatcher
+
+  {% for level in Severity.constants %}
+    {% unless level == "SILENT" %}
+      def {{ level.downcase.id }}(message, *, time = Time.now, line_number = __LINE__, filename = __FILE__)
+        dispatcher.call Entry.new(message, Severity::{{ level }}, component, time, line_number, filename)
+      end
+    {% end %}
+  {% end %}
 
-  # Creates a new logger that will log to the given *io*.
-  # If *io* is `nil` then all log calls will be silently ignored.
-  def initialize(@io : IO?, @level = Severity::INFO, @formatter = DEFAULT_FORMATTER, @progname = "")
-    @closed = false
-    @mutex = Mutex.new
+  def initialize(@component, @dispatcher)
   end
 
-  # Calls the *close* method on the object passed to `initialize`.
-  def close
-    return if @closed
-    return unless io = @io
-    @closed = true
+  class_getter default_dispatcher = Dispatcher.new(nil, IOEmitter.new)
 
-    @mutex.synchronize do
-      io.close
-    end
+  def self.get(component) : Logger
+    default_dispatcher.get component
   end
 
-  {% for name in Severity.constants %}
-    {{name.id}} = Severity::{{name.id}}
-
-    # Returns `true` if the logger's current severity is lower or equal to `{{name.id}}`.
-    def {{name.id.downcase}}?
-      level <= Severity::{{name.id}}
-    end
-
-    # Logs *message* if the logger's current severity is lower or equal to `{{name.id}}`.
-    # *progname* overrides a default progname set in this logger.
-    def {{name.id.downcase}}(message, progname = nil)
-      log(Severity::{{name.id}}, message, progname)
-    end
-
-    # Logs the message as returned from the given block if the logger's current severity
-    # is lower or equal to `{{name.id}}`. The block is not run if the severity is higher.
-    # *progname* overrides a default progname set in this logger.
-    def {{name.id.downcase}}(progname = nil)
-      log(Severity::{{name.id}}, progname) { yield }
-    end
+  {% for level in Severity.constants %}
+    {{ level }} = Severity::{{ level }}
   {% end %}
-
-  # Logs *message* if *severity* is higher or equal with the logger's current
-  # severity. *progname* overrides a default progname set in this logger.
-  def log(severity, message, progname = nil)
-    return if severity < level || !@io
-    write(severity, Time.now, progname || @progname, message)
-  end
-
-  # Logs the message as returned from the given block if *severity*
-  # is higher or equal with the loggers current severity. The block is not run
-  # if *severity* is lower. *progname* overrides a default progname set in this logger.
-  def log(severity, progname = nil)
-    return if severity < level || !@io
-    write(severity, Time.now, progname || @progname, yield)
-  end
-
-  private def write(severity, datetime, progname, message)
-    io = @io
-    return unless io
-
-    progname_to_s = progname.to_s
-    message_to_s = message.to_s
-    @mutex.synchronize do
-      formatter.call(severity, datetime, progname_to_s, message_to_s, io)
-      io.puts
-      io.flush
-    end
-  end
 end
diff --git a/src/logger/dispatcher.cr b/src/logger/dispatcher.cr
new file mode 100644
index 000000000000..6648c57ab089
--- /dev/null
+++ b/src/logger/dispatcher.cr
@@ -0,0 +1,34 @@
+require "./emitter"
+
+struct Logger
+  alias FilterType = Filter | Severity | (Entry -> Bool)
+  alias EmitterType = Emitter | (Entry -> Nil)
+
+  class Dispatcher
+    include Emitter
+
+    property filter : FilterType?
+    property emitters : Array(EmitterType)
+
+    def initialize(@filter, @emitters)
+    end
+
+    def self.new(filter, emitter : EmitterType)
+      new(filter, [emitter] of EmitterType)
+    end
+
+    def call(entry : Entry)
+      case ff = filter
+      when Filter, Proc(Entry, Bool)
+        return unless ff.call(entry)
+      when Severity
+        return unless entry.severity >= ff
+      end
+      emitters.each &.call(entry)
+    end
+
+    def get(component) : Logger
+      Logger.new(component.to_s, self)
+    end
+  end
+end
diff --git a/src/logger/emitter.cr b/src/logger/emitter.cr
new file mode 100644
index 000000000000..8a2043200e9a
--- /dev/null
+++ b/src/logger/emitter.cr
@@ -0,0 +1,24 @@
+require "./entry"
+
+struct Logger
+  module Emitter
+    abstract def call(entry : Entry) : Nil
+  end
+
+  class IOEmitter
+    include Emitter
+
+    DEFAULT_FORMATTER = ->(io : IO, entry : Entry) do
+      io << entry.time << ' ' << entry.severity.to_s.ljust(5) << " ::"
+      io << entry.component << " " << entry.message << '\n'
+      return nil
+    end
+
+    def initialize(@io : IO = STDOUT, @formatter : Proc(IO, Entry, Nil) = DEFAULT_FORMATTER)
+    end
+
+    def call(entry : Entry) : Nil
+      @formatter.call(@io, entry)
+    end
+  end
+end
diff --git a/src/logger/entry.cr b/src/logger/entry.cr
new file mode 100644
index 000000000000..5146a767179d
--- /dev/null
+++ b/src/logger/entry.cr
@@ -0,0 +1,15 @@
+require "./severity"
+
+struct Logger
+  struct Entry
+    getter message : String
+    getter severity : Severity
+    getter component : String
+    getter time : Time
+    getter line_number : Int32
+    getter filename : String
+
+    def initialize(@message, @severity, @component, @time, @line_number, @filename)
+    end
+  end
+end
diff --git a/src/logger/filter.cr b/src/logger/filter.cr
new file mode 100644
index 000000000000..c4b908096510
--- /dev/null
+++ b/src/logger/filter.cr
@@ -0,0 +1,31 @@
+require "./entry"
+
+struct Logger
+  module Filter
+    abstract def call(entry : Entry) : Bool
+  end
+
+  class HierarchyFilter
+    include Filter
+
+    property levels : Hash(String, Severity)
+
+    def initialize(@levels = {} of String => Severity)
+    end
+
+    def call(entry : Entry)
+      component = entry.component
+      while true
+        if level = @levels[component]?
+          return entry.severity >= level
+        end
+        break if component.empty?
+        component = component[0...(component.rindex("::") || 0)]
+      end
+
+      return true
+    end
+
+    forward_missing_to @levels
+  end
+end
diff --git a/src/logger/severity.cr b/src/logger/severity.cr
new file mode 100644
index 000000000000..506947b90e77
--- /dev/null
+++ b/src/logger/severity.cr
@@ -0,0 +1,17 @@
+struct Logger
+  # A logger severity level.
+  enum Severity
+    # Low-level information for developers
+    DEBUG
+    # Generic (useful) information about system operation
+    INFO
+    # A warning
+    WARN
+    # A handleable error condition
+    ERROR
+    # An unhandleable error that results in a program crash
+    FATAL
+    # A level that should never be used in messages but may be useful for setting thresholds
+    SILENT
+  end
+end