diff --git a/examples/sftp.cr b/examples/sftp.cr
index b91f1b5..40e9db7 100644
--- a/examples/sftp.cr
+++ b/examples/sftp.cr
@@ -3,8 +3,8 @@ require "../src/ssh2"
 SSH2::Session.open("localhost", 2222) do |session|
   session.login_with_pubkey("root", "./spec/keys/id_rsa")
   session.sftp_session do |sftp|
-    sftp.open_dir(".").ll do |fn|
-      puts fn
+    sftp.open_dir(".").ll do |file_name|
+      puts file_name
     end
     file = sftp.open(".bashrc")
     puts file.read
diff --git a/examples/shell.cr b/examples/shell.cr
index 88792f8..ffecefc 100644
--- a/examples/shell.cr
+++ b/examples/shell.cr
@@ -2,24 +2,24 @@ require "../src/ssh2"
 
 SSH2::Session.open("my_server") do |session|
   session.login("username", "password")
-  session.open_session do |ch|
-    ch.request_pty("vt100")
-    ch.shell
+  session.open_session do |chan|
+    chan.request_pty("vt100")
+    chan.shell
     session.blocking = false
 
     buf_space = Bytes.new(1024)
     buf = buf_space.to_slice
     loop do
-      io = IO.select([STDIN, ch.socket]).first
+      io = IO.select([STDIN, chan.socket]).first
       if io == STDIN
         command = gets
         if command
-          ch.write(command.to_slice)
+          chan.write(command.to_slice)
         end
-      elsif io == ch.socket
-        len = ch.read(buf).to_i32
+      elsif io == chan.socket
+        len = chan.read(buf).to_i32
         print! String.new buf[0, len]
-        break if ch.eof?
+        break if chan.eof?
       end
     end
   end
diff --git a/spec/ssh2_spec.cr b/spec/ssh2_spec.cr
index 5609c5b..a7e4c2b 100644
--- a/spec/ssh2_spec.cr
+++ b/spec/ssh2_spec.cr
@@ -4,7 +4,7 @@ require "spec"
 SPEC_SSH_HOST = ENV["SPEC_SSH_HOST"]? || "localhost"
 SPEC_SSH_PORT = ENV["CI"]? ? 22 : 10022
 
-def connect_ssh
+def connect_ssh(&)
   SSH2::Session.open(SPEC_SSH_HOST, SPEC_SSH_PORT) do |session|
     session.login("root", "somepassword")
     session.authenticated?.should be_true
@@ -48,16 +48,16 @@ describe SSH2 do
   it "should be able to scp transfer file" do
     fn = "#{Time.utc.to_unix}.txt"
     connect_ssh do |session|
-      session.scp_send(fn, 0o0644, 12) do |ch|
-        ch.puts "hello world"
+      session.scp_send(fn, 0o0644, 12) do |chan|
+        chan.puts "hello world"
       end
-      session.open_session do |ch|
-        ch.command("ls -l")
-        ch.gets_to_end.includes?(fn).should be_true
+      session.open_session do |chan|
+        chan.command("ls -l")
+        chan.gets_to_end.includes?(fn).should be_true
       end
-      session.scp_recv(fn) do |ch, st|
-        buf = Slice(UInt8).new(st.st_size.to_i32)
-        ch.read(buf)
+      session.scp_recv(fn) do |chan, stat|
+        buf = Slice(UInt8).new(stat.st_size.to_i32)
+        chan.read(buf)
         String.new(buf).should eq("hello world\n")
       end
     end
@@ -95,7 +95,7 @@ describe SSH2::KnownHosts do
       known_hosts.size.should eq(2)
       known_hosts.map(&.name).includes?(SPEC_SSH_HOST).should be_true
       known_hosts.write_file("known_hosts")
-      known_hosts.delete_if { |h| h.name == SPEC_SSH_HOST }
+      known_hosts.delete_if { |host| host.name == SPEC_SSH_HOST }
       known_hosts.size.should eq(1)
     end
 
diff --git a/src/agent.cr b/src/agent.cr
index 941fb5b..7dcfdbc 100644
--- a/src/agent.cr
+++ b/src/agent.cr
@@ -52,7 +52,7 @@ class SSH2::Agent
     raise SSH2Error.new "Failed to authenticate username #{username} with SSH agent"
   end
 
-  def each
+  def each(&)
     each_unsafe do |key|
       yield PublicKey.new(
         Slice.new(key.value.blob, key.value.blob_len),
@@ -60,7 +60,7 @@ class SSH2::Agent
     end
   end
 
-  private def each_unsafe
+  private def each_unsafe(&)
     prev = Pointer(LibSSH2::AgentPublicKey).null
     until LibSSH2.agent_get_identity(self, out store, prev) == 1
       yield store
diff --git a/src/channel.cr b/src/channel.cr
index 226461c..8d7bea5 100644
--- a/src/channel.cr
+++ b/src/channel.cr
@@ -13,7 +13,7 @@ class SSH2::Channel < IO
   end
 
   def socket
-    @session.socket.not_nil!
+    @session.socket.as(TCPSocket)
   end
 
   # Close an active data channel. In practice this means sending an
diff --git a/src/known_hosts.cr b/src/known_hosts.cr
index a842e3a..6db9b97 100644
--- a/src/known_hosts.cr
+++ b/src/known_hosts.cr
@@ -29,7 +29,7 @@ class SSH2::KnownHosts
     LibSSH2.knownhost_checkp(self, host, port, key, key.size.to_u64, typemask, out store)
   end
 
-  def delete_if
+  def delete_if(&)
     each_unsafe do |known_host|
       if yield conv_to_host(known_host)
         ret = LibSSH2.knownhost_del(self, known_host)
@@ -53,7 +53,7 @@ class SSH2::KnownHosts
     check_error(ret)
   end
 
-  def each
+  def each(&)
     each_unsafe do |known_host|
       yield conv_to_host(known_host)
     end
@@ -65,7 +65,7 @@ class SSH2::KnownHosts
     Host.new(name, key, known_host.value.typemask)
   end
 
-  private def each_unsafe
+  private def each_unsafe(&)
     prev = Pointer(LibSSH2::KnownHost).null
     until LibSSH2.knownhost_get(self, out store, prev) == 1
       yield store
diff --git a/src/session.cr b/src/session.cr
index 1233846..1358852 100644
--- a/src/session.cr
+++ b/src/session.cr
@@ -23,7 +23,7 @@ class SSH2::Session
     new(socket)
   end
 
-  def self.open(host : String, port = 22)
+  def self.open(host : String, port = 22, &)
     TCPSocket.open(host, port) do |socket|
       session = new(socket)
       begin
@@ -40,7 +40,7 @@ class SSH2::Session
     @socket.wait_writable if flags.outbound?
   end
 
-  def perform_nonblock
+  def perform_nonblock(&)
     loop do
       result = @request_lock.synchronize { yield }
       code = if result.is_a?(Tuple)
@@ -57,7 +57,7 @@ class SSH2::Session
     end
   end
 
-  def nonblock_handle
+  def nonblock_handle(&)
     loop do
       result = @request_lock.synchronize { yield }
       handle = if result.is_a?(Tuple)
@@ -142,10 +142,6 @@ class SSH2::Session
     @@callbacks_lock.synchronize { @@callbacks.delete object_id }
   end
 
-  private def password_cb(username : String, welcome : String) : String
-    @interactive_cb.not_nil!.call(username, welcome)
-  end
-
   # Login with username using pub/priv key values
   def login_with_data(username : String, privkey : String, pubkey : String, passphrase : String? = nil)
     @socket.wait_writable
@@ -217,10 +213,10 @@ class SSH2::Session
             #  64
           end
     slice = Slice.new(handle, len)
-    String.build do |o|
-      slice.each_with_index do |b, idx|
-        o << b.to_s(16)
-        o << ":" unless idx == length - 1
+    String.build do |outp|
+      slice.each_with_index do |byte, idx|
+        outp << byte.to_s(16)
+        outp << ":" unless idx == length - 1
       end
     end
   end
@@ -287,14 +283,26 @@ class SSH2::Session
   end
 
   # If set, libssh2 will not attempt to block SIGPIPEs but will let them trigger from the underlying socket layer.
+  @[Deprecated("Use `#enable_sigpipe=` instead")]
+  # ameba:disable Naming/AccessorMethodName
   def set_enable_sigpipe(value)
+    self.enable_sigpipe = value
+  end
+
+  def enable_sigpipe=(value)
     perform_nonblock { LibSSH2.session_flag(self, LibSSH2::SessionFlag::SIGPIPE, value ? 1 : 0) }
   end
 
   # If set - before the connection negotiation is performed - libssh2 will try
   # to negotiate compression enabling for this connection. By default libssh2
   # will not attempt to use compression.
+  @[Deprecated("Use `#enable_compression=` instead")]
+  # ameba:disable Naming/AccessorMethodName
   def set_enable_compression(value)
+    self.enable_compression = value
+  end
+
+  def enable_compression=(value)
     perform_nonblock { LibSSH2.session_flag(self, LibSSH2::SessionFlag::COMPRESS, value ? 1 : 0) }
   end
 
@@ -370,7 +378,7 @@ class SSH2::Session
     open_channel("session", LibSSH2::CHANNEL_WINDOW_DEFAULT, LibSSH2::CHANNEL_PACKET_DEFAULT, nil)
   end
 
-  def open_session
+  def open_session(&)
     channel = open_session
     begin
       yield channel
@@ -388,7 +396,7 @@ class SSH2::Session
     Channel.new self, handle
   end
 
-  def direct_tcpip(host, port, source_host, source_port)
+  def direct_tcpip(host, port, source_host, source_port, &)
     channel = direct_tcpip(host, port, source_host, source_port)
     begin
       yield channel
@@ -406,7 +414,7 @@ class SSH2::Session
 
   # Send a file to the remote host via SCP.
   # A new channel is passed to the block and closed afterwards.
-  def scp_send(path, mode, size, mtime = Time.utc.to_unix, atime = Time.utc.to_unix)
+  def scp_send(path, mode, size, mtime = Time.utc.to_unix, atime = Time.utc.to_unix, &)
     channel = scp_send(path, mode, size, mtime, atime)
     begin
       yield channel
@@ -421,9 +429,9 @@ class SSH2::Session
       raise SSH2Error.new("Unable to get stat for '#{path}'")
     end
     scp_send(remote_path, (stat.st_mode & 0x3ff).to_i32, stat.st_size.to_u64,
-      stat.st_mtim.tv_sec, stat.st_atim.tv_sec) do |ch|
-      File.open(path, "r") do |f|
-        IO.copy(f, ch)
+      stat.st_mtim.tv_sec, stat.st_atim.tv_sec) do |chan|
+      File.open(path, "r") do |file|
+        IO.copy(file, chan)
       end
     end
   end
@@ -439,7 +447,7 @@ class SSH2::Session
 
   # Request a file from the remote host via SCP.
   # A new channel is passed to the block and closed afterwards.
-  def scp_recv(path)
+  def scp_recv(path, &)
     channel, stat = scp_recv(path)
     begin
       yield channel, stat
@@ -450,11 +458,11 @@ class SSH2::Session
 
   # Download a file from the remote host via SCP to the local filesystem.
   def scp_recv_file(path, local_path = path)
-    File.open(local_path, "w") do |f|
-      scp_recv(path) do |ch, st|
-        buf = Slice(UInt8).new(st.st_size.to_i32)
-        ch.read(buf)
-        f.write(buf)
+    File.open(local_path, "w") do |file|
+      scp_recv(path) do |chan, stat|
+        buf = Slice(UInt8).new(stat.st_size.to_i32)
+        chan.read(buf)
+        file.write(buf)
       end
     end
   end
@@ -466,7 +474,7 @@ class SSH2::Session
     SFTP::Session.new(self, handle)
   end
 
-  def sftp_session
+  def sftp_session(&)
     sftp = sftp_session
     begin
       yield sftp
diff --git a/src/sftp/dir.cr b/src/sftp/dir.cr
index 941e024..37716ab 100644
--- a/src/sftp/dir.cr
+++ b/src/sftp/dir.cr
@@ -5,7 +5,7 @@ module SSH2::SFTP
     include Node
 
     # Lists a current directory
-    def ls
+    def ls(&)
       loop do
         buf_space = uninitialized UInt8[512]
         buf = buf_space.to_slice
@@ -18,11 +18,11 @@ module SSH2::SFTP
     # Lists a current directory
     def ls
       ret = [] of String
-      ls { |fn| ret << fn }
+      ls { |file_name| ret << file_name }
       ret
     end
 
-    def ll
+    def ll(&)
       loop do
         buf_space = uninitialized UInt8[512]
         buf = buf_space.to_slice
@@ -42,7 +42,7 @@ module SSH2::SFTP
 
     def ll
       ret = [] of String
-      ll { |fn| ret << fn }
+      ll { |file_name| ret << file_name }
       ret
     end
   end