diff --git a/CHANGELOG.md b/CHANGELOG.md
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--- /dev/null
+++ b/CHANGELOG.md
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+# Revision history for ob
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright (c) 2025, Sridhar Ratnakumar
+
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * 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.
+
+    * 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/ob.cabal b/ob.cabal
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--- /dev/null
+++ b/ob.cabal
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+cabal-version:   3.4
+name:            ob
+version:         0.1.0.0
+synopsis:        Live in-memory sync of Obsidian Markdown notes
+
+-- description:
+homepage:        https://github.com/srid/imako
+license:         BSD-3-Clause
+license-file:    LICENSE
+author:          Sridhar Ratnakumar
+maintainer:      srid@srid.ca
+
+-- copyright:
+category:        Text
+build-type:      Simple
+extra-doc-files: CHANGELOG.md
+
+-- extra-source-files:
+
+common warnings
+  ghc-options: -Wall
+
+library
+  import:             warnings
+  exposed-modules:    Ob
+  mixins:
+    base hiding (Prelude),
+    relude (Relude as Prelude, Relude.Container.One),
+    relude
+
+  default-extensions:
+    DataKinds
+    DerivingStrategies
+    DerivingVia
+    LambdaCase
+    MultiWayIf
+    NoStarIsType
+    OverloadedStrings
+    StrictData
+    TypeFamilies
+    ViewPatterns
+
+  -- other-modules:
+  -- other-extensions:
+  build-depends:
+    , aeson
+    , async
+    , base                 ^>=4.18.2.1
+    , commonmark-simple
+    , commonmark-wikilink
+    , containers
+    , filepath
+    , monad-logger
+    , pandoc
+    , pandoc-types
+    , relude
+    , stm
+    , unionmount
+    , unliftio
+
+  hs-source-dirs:     src
+  default-language:   GHC2021
+
+test-suite ob-test
+  import:           warnings
+  default-language: GHC2021
+
+  -- other-modules:
+  -- other-extensions:
+  type:             exitcode-stdio-1.0
+  hs-source-dirs:   test
+  main-is:          Main.hs
+  build-depends:
+    , base  ^>=4.18.2.1
+    , ob
diff --git a/src/Ob.hs b/src/Ob.hs
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--- /dev/null
+++ b/src/Ob.hs
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+{- | Work with Obsidian notebooks in Haskell
+
+WARNING: This package doesn't provide anything useful yet. See the GitHub repo for developmnt progress.
+-}
+module Ob (
+  Note,
+  Notebook,
+  getNotebook,
+  withNotebook,
+)
+where
+
+import Commonmark.Simple qualified as CM
+import Control.Monad.Logger (runStdoutLoggingT)
+import Data.Aeson qualified as Aeson
+import Data.Map.Strict qualified as Map
+import System.FilePath ((</>))
+import System.UnionMount qualified as UM
+import Text.Pandoc.Definition (Pandoc)
+import UnliftIO.Async (concurrently_)
+
+type Note = Either Text (Maybe Aeson.Value, Pandoc)
+
+type Notebook = Map FilePath Note
+
+-- | Like `withNotebook` but returns the current snapshot, without monitoring it.
+getNotebook :: FilePath -> IO Notebook
+getNotebook path = do
+  runStdoutLoggingT $ do
+    (model0, _) <- UM.mount path (one ((), "*.md")) [] mempty (const $ handlePathUpdate path)
+    liftIO $ putTextLn $ "Model ready; initial docs = " <> show (Map.size model0) <> "; sample = " <> show (take 4 $ Map.keys model0)
+    pure model0
+
+withNotebook :: FilePath -> (TVar Notebook -> IO ()) -> IO ()
+withNotebook path f = do
+  runStdoutLoggingT $ do
+    (model0, modelF) <- UM.mount path (one ((), "*.md")) [] mempty (const $ handlePathUpdate path)
+    liftIO $ putTextLn $ "Model ready; initial docs = " <> show (Map.size model0) <> "; sample = " <> show (take 4 $ Map.keys model0)
+    modelVar <- newTVarIO model0
+    concurrently_ (liftIO $ f modelVar) $ do
+      modelF $ \newModel -> do
+        putTextLn $ "Model udpated; total docs = " <> show (Map.size newModel)
+        atomically $ writeTVar modelVar newModel
+
+handlePathUpdate ::
+  (MonadIO m) =>
+  FilePath ->
+  FilePath ->
+  UM.FileAction () ->
+  m (Map FilePath Note -> Map FilePath Note)
+handlePathUpdate baseDir path action = do
+  case action of
+    UM.Refresh _ _ -> do
+      s <- decodeUtf8 <$> readFileBS (baseDir </> path)
+      let doc = CM.parseMarkdownWithFrontMatter @Aeson.Value CM.fullMarkdownSpec path s
+      pure $ Map.insert path doc
+    UM.Delete -> do
+      pure $ Map.delete path
diff --git a/test/Main.hs b/test/Main.hs
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--- /dev/null
+++ b/test/Main.hs
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+module Main (main) where
+
+main :: IO ()
+main = putStrLn "Test suite not yet implemented."