diff --git a/.github/workflows/plugins.yml b/.github/workflows/plugins.yml
index 4556215f1..3de7288eb 100644
--- a/.github/workflows/plugins.yml
+++ b/.github/workflows/plugins.yml
@@ -118,9 +118,12 @@ jobs:
     - name: clone https://github.com/lekemula/solargraph-rspec/
       run: |
        cd ..
-       git clone https://github.com/lekemula/solargraph-rspec.git
+       # git clone https://github.com/lekemula/solargraph-rspec.git
 
+       # pending https://github.com/lekemula/solargraph-rspec/pull/31
+       git clone https://github.com/apiology/solargraph-rspec.git
        cd solargraph-rspec
+       git checkout test_solargraph_prereleases
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
diff --git a/.gitignore b/.gitignore
index 2819165b1..75510d96b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,3 +14,4 @@ coverage
 /Makefile
 /.pryrc
 /.rspec-local
+vendor/cache
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 315ba0c73..e07381830 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
+## 0.58.2 - January 19, 2026
+- Avoid rbs pollution (#1146)
+- Fix 'solargraph pin --references ClassName' private method call (#1150)
+- Improve memory efficiency of Position class (#1054)
+- Raise InvalidOffsetError for offsets > text (#1155)
+
 ## 0.58.1 - January 2, 2026
--  Normalize line endings to LF (#1142)
+- Normalize line endings to LF (#1142)
 
 ## 0.58.0 - January 1, 2026
 - Faster constant resolution (#1083)
diff --git a/lib/solargraph/position.rb b/lib/solargraph/position.rb
index 53c7b61ba..332ffa527 100644
--- a/lib/solargraph/position.rb
+++ b/lib/solargraph/position.rb
@@ -57,7 +57,24 @@ def inspect
     # @return [Integer]
     def self.to_offset text, position
       return 0 if text.empty?
-      text.lines[0...position.line].sum(&:length) + position.character
+
+      newline_index = -1
+      line = -1
+      last_line_index = 0
+
+      # @sg-ignore flow sensitive typing should be able to handle redefinition
+      while (newline_index = text.index("\n", newline_index + 1)) && line <= position.line
+        line += 1
+        break if line == position.line
+
+        # @sg-ignore oflow sensitive typing should be able to handle redefinition
+        line_length = newline_index - last_line_index
+        last_line_index = newline_index
+      end
+
+      last_line_index += 1 if position.line > 0
+      # @sg-ignore flow sensitive typing should be able to handle redefinition
+      last_line_index + position.character
     end
 
     # Get a numeric offset for the specified text and a position identified
@@ -73,23 +90,24 @@ def self.line_char_to_offset text, line, character
 
     # Get a position for the specified text and offset.
     #
+    # @raise [InvalidOffsetError] if the offset is outside the text range
+    #
     # @param text [String]
     # @param offset [Integer]
     # @return [Position]
     def self.from_offset text, offset
+      raise InvalidOffsetError if offset > text.length
+
       cursor = 0
       line = 0
-      # @type [Integer, nil]
-      character = nil
-      text.lines.each do |l|
-        line_length = l.length
-        char_length = l.chomp.length
-        if cursor + char_length >= offset
-          character = offset - cursor
-          break
-        end
-        cursor += line_length
+      character = offset
+      newline_index = -1
+
+      # @sg-ignore flow sensitive typing should be able to handle redefinition
+      while (newline_index = text.index("\n", newline_index + 1)) && newline_index < offset
         line += 1
+        # @sg-ignore flow sensitive typing should be able to handle redefinition
+        character = offset - newline_index - 1
       end
       character = 0 if character.nil? and (cursor - offset).between?(0, 1)
       raise InvalidOffsetError if character.nil?
diff --git a/lib/solargraph/version.rb b/lib/solargraph/version.rb
index bfe833039..00cc77b02 100755
--- a/lib/solargraph/version.rb
+++ b/lib/solargraph/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Solargraph
-  VERSION = ENV.fetch('SOLARGRAPH_FORCE_VERSION', '0.59.0.dev.1')
+  VERSION = ENV.fetch('SOLARGRAPH_FORCE_VERSION', '0.59.0.dev.2')
 end
diff --git a/spec/position_spec.rb b/spec/position_spec.rb
index fa30cf7d9..e8dab1960 100644
--- a/spec/position_spec.rb
+++ b/spec/position_spec.rb
@@ -12,9 +12,38 @@
     expect(orig).to be(norm)
   end
 
+  it 'finds offset from position' do
+    text = "\n      class Foo\n        def bar baz, boo = 'boo'\n        end\n      end\n    "
+    expect(Solargraph::Position.to_offset(text, Solargraph::Position.new(0, 0))).to eq(0)
+    expect(Solargraph::Position.to_offset(text, Solargraph::Position.new(0, 4))).to eq(4)
+    expect(Solargraph::Position.to_offset(text, Solargraph::Position.new(2, 12))).to eq(29)
+    expect(Solargraph::Position.to_offset(text, Solargraph::Position.new(2, 27))).to eq(44)
+    expect(Solargraph::Position.to_offset(text, Solargraph::Position.new(3, 8))).to eq(58)
+  end
+
+  it 'constructs position from offset' do
+    text = "\n      class Foo\n        def bar baz, boo = 'boo'\n        end\n      end\n    "
+    expect(Solargraph::Position.from_offset(text, 0)).to eq(Solargraph::Position.new(0, 0))
+    expect(Solargraph::Position.from_offset(text, 4)).to eq(Solargraph::Position.new(1, 3))
+    expect(Solargraph::Position.from_offset(text, 29)).to eq(Solargraph::Position.new(2, 12))
+    expect(Solargraph::Position.from_offset(text, 44)).to eq(Solargraph::Position.new(2, 27))
+  end
+
   it "raises an error for objects that cannot be normalized" do
     expect {
       Solargraph::Position.normalize('0, 1')
     }.to raise_error(ArgumentError)
   end
+
+  it 'avoids fencepost errors' do
+    text = "      class Foo\n        def bar baz, boo = 'boo'\n        end\n      end\n    "
+    offset = Solargraph::Position.to_offset(text, Solargraph::Position.new(3, 6))
+    expect(offset).to eq(67)
+  end
+
+  it 'avoids fencepost errors with multiple blank lines' do
+    text = "      class Foo\n        def bar baz, boo = 'boo'\n\n        end\n      end\n    "
+    offset = Solargraph::Position.to_offset(text, Solargraph::Position.new(4, 6))
+    expect(offset).to eq(68)
+  end
 end