diff --git a/CHANGELOG.md b/CHANGELOG.md
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--- /dev/null
+++ b/CHANGELOG.md
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+# Changelog
+
+0.2.0.5 Package as flake.
+
+0.2.0.4 Updated dependencies.
+
+0.2.0.3 Reformatted source code.
+
+0.1.0.0 Initial release
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+BSD 3-Clause License
+
+Copyright (c) 2022-2023, Amy de Buitléir
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/app/Main.hs b/app/Main.hs
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--- /dev/null
+++ b/app/Main.hs
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+{-|
+Module      : Main
+Description : An easy way to create tables with wrapped text in Markdown.
+Copyright   : (c) 2020-2023 Amy de Buitléir
+License     : BSD--3
+Maintainer  : amy@nualeargais.ie
+Stability   : experimental
+Portability : POSIX
+
+See <https://github.com/mhwombat/pandoc-columns> for information
+on how to use this filter.
+-}
+import Text.Pandoc.Filters.Columns (formatColumns)
+import Text.Pandoc.JSON            (toJSONFilter)
+
+main :: IO ()
+main = toJSONFilter formatColumns
diff --git a/pandoc-columns.cabal b/pandoc-columns.cabal
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--- /dev/null
+++ b/pandoc-columns.cabal
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+cabal-version:   3.0
+name:            pandoc-columns
+version:         0.2.0.5
+synopsis:
+    A pandoc filter that provides a Markdown extension for columns.
+description:
+  For more information and a tutorial on how to use this package,
+  please see the README at <https://github.com/mhwombat/pandoc-columns#readme>.
+homepage:        https://github.com/mhwombat/pandoc-columns
+bug-reports:     https://github.com/mhwombat/pandoc-columns/issues
+license:         BSD-3-Clause
+license-file:    LICENSE
+author:          Amy de Buitléir
+maintainer:      amy@nualeargais.ie
+copyright:       (c) 2020-2023 Amy de Buitléir
+category:        Text
+build-type:      Simple
+extra-doc-files: CHANGELOG.md
+
+source-repository head
+  type:              git
+  location:          https://github.com/mhwombat/pandoc-columns.git
+
+common common-stuff
+  default-language: Haskell2010
+  default-extensions: ImportQualifiedPost
+  build-depends:
+    base >= 4.16.4 && < 4.17,
+    pandoc-types >= 1.22.2 && < 1.23
+  ghc-options: -Wall  -Wunused-packages
+
+library
+  import:           common-stuff
+  hs-source-dirs:   src
+  exposed-modules:  Text.Pandoc.Filters.Columns
+  build-depends:
+    pandoc >= 2.19.2 && < 2.20
+
+executable pandoc-columns
+  import:           common-stuff
+  hs-source-dirs:   app
+  main-is:          Main.hs
+  build-depends:
+    pandoc-columns
+
diff --git a/src/Text/Pandoc/Filters/Columns.hs b/src/Text/Pandoc/Filters/Columns.hs
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--- /dev/null
+++ b/src/Text/Pandoc/Filters/Columns.hs
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+{-|
+Module      : Columns
+Description : Pandoc filter to support columns in Markdown.
+Copyright   : (c) 2020-2023 Amy de Buitléir
+License     : BSD--3
+Maintainer  : amy@nualeargais.ie
+Stability   : experimental
+Portability : POSIX
+
+See <https://github.com/mhwombat/pandoc-linear-table> for information
+on how to use this filter.
+-}
+
+{-# LANGUAGE OverloadedStrings #-}
+module Text.Pandoc.Filters.Columns
+  (
+    transform,
+    formatColumns
+  ) where
+
+import Text.Pandoc      qualified as P
+import Text.Pandoc.Walk (walk)
+
+
+-- | A transformation that can be used with Hakyll.
+transform :: P.Pandoc -> P.Pandoc
+transform = walk formatColumns
+
+formatColumns :: P.Block -> P.Block
+formatColumns (P.Div attr@(_,["columns"],_) bs)
+  = P.Table attr defaultTableCaption colSpecs
+                    defaultTableHeader [body]
+                    defaultTableFooter
+  where body = blocksToTableBody bs
+        colSpecs = map (const defaultColSpec) bs
+formatColumns b = b
+
+blocksToTableBody :: [P.Block] -> P.TableBody
+blocksToTableBody bs = P.TableBody P.nullAttr (P.RowHeadColumns 0) [] [row]
+  where row = blocksToTableRow bs
+
+blocksToTableRow :: [P.Block] -> P.Row
+blocksToTableRow = P.Row P.nullAttr . map blockToCell
+
+blockToCell :: P.Block -> P.Cell
+blockToCell b = P.Cell P.nullAttr P.AlignDefault (P.RowSpan 1) (P.ColSpan 1) [b]
+
+defaultColSpec :: P.ColSpec
+defaultColSpec = (P.AlignDefault, P.ColWidthDefault)
+
+defaultTableCaption :: P.Caption
+defaultTableCaption = P.Caption Nothing []
+
+defaultTableHeader :: P.TableHead
+defaultTableHeader = P.TableHead P.nullAttr []
+
+defaultTableFooter :: P.TableFoot
+defaultTableFooter = P.TableFoot P.nullAttr []