Format code with fourmolu

AGENTS.md

@@ -0,0 +1,76 @@
+# AGENTS.md
+
+## Project Overview
+
+`orville-sqlite` is a Haskell library providing a type-safe SQLite API modeled after the [Flipstone Orville](https://github.com/flipstone/orville/) PostgreSQL library. It maps Haskell data types to SQLite tables with compile-time schema guarantees.
+
+## Development Environment
+
+**All development happens inside Docker.** No local Haskell tools should be installed directly on the host machine.
+
+Use the `./hs` wrapper script for all Haskell tooling:
+
+```bash
+./hs stack build
+./hs stack test
+./hs stack ghci
+./hs fourmolu -i src/
+./hs hlint src/
+```
+
+The script builds a Docker image based on `ghcr.io/flipstone/haskell-tools:debian-ghc-9.10.3-5d6640d` with `libsqlite3-dev` installed. A named Docker volume (`orville-sqlite-stack-root`) caches GHC and dependencies across worktrees.
+
+## Build System
+
+- **GHC**: 9.10.3
+- **Build tool**: Stack (via the `hs` wrapper)
+- **Formatter**: fourmolu
+- **Linter**: hlint
+
+## Dependencies
+
+- **Base SQLite library**: [direct-sqlite](https://github.com/IreneKnapp/direct-sqlite) — the low-level FFI binding to SQLite
+- This library builds type-safe marshalling, auto-migration, and query execution on top of `direct-sqlite`
+
+## Target API
+
+The library should provide APIs analogous to three key modules from `orville-postgresql`:
+
+1. **`Orville.PostgreSQL.Marshall.SqlMarshaller`** — Type-safe mapping between Haskell records and SQL table columns
+2. **`Orville.PostgreSQL.AutoMigration`** — Schema migration: create tables if they don't exist, alter tables to match expected schema
+3. **`Orville.PostgreSQL.Execution`** — Query execution: SELECT, INSERT, UPDATE against typed tables
+
+### Example Usage (Target API)
+
+Given a Haskell type:
+
+```haskell
+data Person = Person
+  { firstName :: Text
+  , lastName  :: Text
+  , age       :: Int
+  }
+```
+
+It should map to a table:
+
+```sql
+CREATE TABLE person (
+    first_name VARCHAR(100) NOT NULL,
+    last_name  VARCHAR(100) NOT NULL,
+    age        INT
+);
+```
+
+And support:
+- Creating the table if it doesn't exist
+- Altering the table to match the schema when columns differ
+- Querying rows as `Person` values
+- Inserting `Person` values
+- Updating rows from `Person` values
+
+## Design Principles
+
+- Haskell types to SQLite schema — not a direct port of the PostgreSQL implementation
+- Follow the spirit and API shape of Orville, adapted to SQLite's type system and SQL dialect
+- Favor type safety and compile-time guarantees over runtime flexibility

README.md

@@ -0,0 +1,61 @@
+# orville-sqlite
+
+This library is intended to be a SQLite Haskell API similar in spirit to https://github.com/flipstone/orville/
+
+The goal of this library is to provide a type safe approach to mapping Haskell types to SQLite data. We aim for type-safe queries and migrations.
+
+The Flipstone orville library is robust and deep. This library aspires to the same but realizes it's unlikely to get there anytime soon.
+
+## Goal
+
+This library intends to provide a similar API for describing the database schema and executing queries as the Flipstone Orville library.
+
+We will not port the PostgreSQL implementation directly but instead target a similar API.
+
+The APIs that concern us the most are:
+
+- Orville.PostgreSQL.Marshall.SqlMarshaller
+- Orville.PostgreSQL.AutoMigration as AutoMigration
+- Orville.PostgreSQL.Execution
+
+and even for those, we only what's strictly necessary to define a way to take a Haskell data type like
+
+```haskell
+
+data Person =
+  Person
+    { firstName :: Text
+    , lastName :: Text
+    , age :: Int
+    }
+```
+
+and map it to a table of schema
+
+```sql
+CREATE TABLE person (
+    first_name VARCHAR(100) NOT NULL,
+    last_name  VARCHAR(100) NOT NULL,
+    age        INT
+);
+```
+
+and then give us an API for marshalling that Haskell type to that table definition
+
+then using that marshaller we should have APIs that can;
+
+- create the table if it does not exist
+- alter the table to match the schema if the table does exist but its columns don't match
+- query the table and retrieve Person values
+- insert Person values into the table
+- update the table from Person values.
+
+## Development environment
+
+The development environment should be entirely inside of Docker - no local
+tools should be installed on the machine directly. use the `hs` wrapper script
+to execute Haskell tooling inside of Docker.
+
+## Base SQLite library
+
+Our base library for interacting with SQLite should be direct-sqlite - https://github.com/IreneKnapp/direct-sqlite

hs

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# Thin wrapper to run Haskell tooling (stack, hpack, fourmolu, hlint, ...)
+# inside a Docker image with our system dependencies pre-installed.
+# Usage: ./hs <cmd> [args]
+set -euo pipefail
+
+PROJECT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# Build a custom image on top of flipstone/haskell-tools that includes
+# the C libraries our Haskell packages need (e.g. libsqlite3-dev).
+IMAGE="orville-sqlite-haskell-tools"
+
+docker build \
+  --quiet \
+  -t "${IMAGE}" \
+  -f - \
+  "${PROJECT_DIR}" << DOCKERFILE
+FROM ghcr.io/flipstone/haskell-tools:debian-ghc-9.10.3-5d6640d
+RUN apt-get update -qq && apt-get install -y -qq libsqlite3-dev
+DOCKERFILE
+
+# Named Docker volume shared across all worktrees so cached
+# GHC/dependencies don't need rebuilding per worktree.
+STACK_ROOT_VOLUME="orville-sqlite-stack-root"
+
+docker volume inspect "${STACK_ROOT_VOLUME}" > /dev/null 2>&1 || \
+  docker volume create "${STACK_ROOT_VOLUME}" > /dev/null
+
+exec docker run --rm -i $([ -t 0 ] && printf -- -t) \
+  -v "${PROJECT_DIR}:/work" \
+  -v "${STACK_ROOT_VOLUME}:/stack-root" \
+  -e STACK_ROOT=/stack-root \
+  -w /work/orville-sqlite \
+  "${IMAGE}" \
+  "$@"

src/Orville/SQLite/AutoMigration.hs

@@ -3,16 +3,16 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 
-module Orville.SQLite.AutoMigration
-  ( MigrationOptions (..)
-  , defaultOptions
-  , SchemaItem (..)
-  , schemaTable
-  , dropColumns
-  , autoMigrateSchema
-  , MigrationStep (..)
-  , generateMigrationPlan
-  , executeMigrationPlan
+module Orville.SQLite.AutoMigration (
+    MigrationOptions (..),
+    defaultOptions,
+    SchemaItem (..),
+    schemaTable,
+    dropColumns,
+    autoMigrateSchema,
+    MigrationStep (..),
+    generateMigrationPlan,
+    executeMigrationPlan,
 ) where
 
 import Control.Monad (when)
@@ -23,12 +23,12 @@ import qualified Data.Text as T
 import qualified Database.SQLite3 as SQLite3
 import Orville.SQLite.FieldDefinition (fieldColumnName)
 import Orville.SQLite.Monad (OrvilleM)
-import Orville.SQLite.SqlMarshaller
-  ( FieldInfo (..)
-  , SqlMarshaller
-  , marshallerFieldInfo
+import Orville.SQLite.SqlMarshaller (
+    FieldInfo (..),
+    SqlMarshaller,
+    marshallerFieldInfo,
  )
-import Orville.SQLite.TableDefinition (TableDefinition (..), PrimaryKey (..))
+import Orville.SQLite.TableDefinition (PrimaryKey (..), TableDefinition (..))
 
 data MigrationOptions = MigrationOptions
     { runSchemaChanges :: Bool
@@ -47,7 +47,8 @@ data SchemaItemRep where
         , schemaItemMarshaller :: SqlMarshaller w r
         , schemaItemPkName :: String
         , schemaItemDropColumns :: [String]
-    } -> SchemaItemRep
+        } ->
+        SchemaItemRep
 
 schemaTable ::
     TableDefinition key writeEntity readEntity ->

src/Orville/SQLite/Execution.hs

@@ -2,12 +2,12 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
-module Orville.SQLite.Execution
-  ( insertEntity
-  , findEntity
-  , findAll
-  , updateEntity
-  , deleteEntity
+module Orville.SQLite.Execution (
+    insertEntity,
+    findEntity,
+    findAll,
+    updateEntity,
+    deleteEntity,
 ) where
 
 import Control.Monad.IO.Class (liftIO)
@@ -18,12 +18,12 @@ import qualified Database.SQLite3 as SQLite3
 import Database.SQLite3.Direct (columnCount)
 import Orville.SQLite.FieldDefinition (fieldColumnName, fieldToSqlValue)
 import Orville.SQLite.Monad (OrvilleM)
-import Orville.SQLite.SqlMarshaller
-  ( marshallerDerivedColumns
-  , marshallerEncodeWrite
-  , marshallerDecodeRow
+import Orville.SQLite.SqlMarshaller (
+    marshallerDecodeRow,
+    marshallerDerivedColumns,
+    marshallerEncodeWrite,
  )
-import Orville.SQLite.TableDefinition (TableDefinition (..), PrimaryKey (..))
+import Orville.SQLite.TableDefinition (PrimaryKey (..), TableDefinition (..))
 
 insertEntity ::
     TableDefinition key writeEntity readEntity ->

src/Orville/SQLite/FieldDefinition.hs

@@ -3,37 +3,37 @@
 {-# LANGUAGE KindSignatures #-}
 {-# LANGUAGE LambdaCase #-}
 
-module Orville.SQLite.FieldDefinition
-  ( Nullability (..)
-  , FieldDefinition (..)
-  , integerField
-  , textField
-  , realField
-  , blobField
-  , nullableField
-  , convertField
-  , fieldToSqlValue
-  , fieldFromSqlValue
-  , fieldColumnName
-  , fieldSqlTypeName
-  , fieldIsNullable
+module Orville.SQLite.FieldDefinition (
+    Nullability (..),
+    FieldDefinition (..),
+    integerField,
+    textField,
+    realField,
+    blobField,
+    nullableField,
+    convertField,
+    fieldToSqlValue,
+    fieldFromSqlValue,
+    fieldColumnName,
+    fieldSqlTypeName,
+    fieldIsNullable,
 ) where
 
-import Data.Kind (Type)
 import qualified Data.ByteString as BS
 import Data.Int (Int64)
+import Data.Kind (Type)
 import qualified Data.Text as T
 import qualified Database.SQLite3 as SQLite3
-import Orville.SQLite.SqlType
-  ( SqlType
-  , convertSqlType
-  , integerType
-  , realType
-  , blobType
-  , sqlTypeFromSql
-  , sqlTypeName
-  , sqlTypeToSql
-  , textType
+import Orville.SQLite.SqlType (
+    SqlType,
+    blobType,
+    convertSqlType,
+    integerType,
+    realType,
+    sqlTypeFromSql,
+    sqlTypeName,
+    sqlTypeToSql,
+    textType,
  )
 
 data Nullability = NotNull | Nullable
@@ -42,11 +42,13 @@ data FieldDefinition (nullability :: Nullability) :: Type -> Type where
     NotNullField ::
         { notNullFieldName :: String
         , notNullFieldSqlType :: SqlType a
-    } -> FieldDefinition 'NotNull a
+        } ->
+        FieldDefinition 'NotNull a
     NullableField ::
         { nullableFieldName :: String
         , nullableFieldSqlType :: SqlType a
-    } -> FieldDefinition 'Nullable a
+        } ->
+        FieldDefinition 'Nullable a
 
 fieldColumnName :: FieldDefinition null a -> String
 fieldColumnName = \case

src/Orville/SQLite/Monad.hs

@@ -1,17 +1,17 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE OverloadedStrings #-}
 
-module Orville.SQLite.Monad
-  ( OrvilleM
-  , withConnection
-  , openConnection
-  , closeConnection
-  , runOrvilleM
-  , withTransaction
+module Orville.SQLite.Monad (
+    OrvilleM,
+    withConnection,
+    openConnection,
+    closeConnection,
+    runOrvilleM,
+    withTransaction,
 ) where
 
 import Control.Monad.IO.Class (MonadIO (liftIO))
-import Control.Monad.Reader (ReaderT, runReaderT, ask, MonadReader)
+import Control.Monad.Reader (MonadReader, ReaderT, ask, runReaderT)
 import qualified Data.Text as T
 import qualified Database.SQLite3 as SQLite3
 

src/Orville/SQLite/RawSql.hs

@@ -1,16 +1,16 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 
-module Orville.SQLite.RawSql
-  ( RawSql (..)
-  , fromString
-  , toRawSql
-  , intercalate
-  , fromText
-  , space
-  , comma
-  , leftParen
-  , rightParen
-  , equals
+module Orville.SQLite.RawSql (
+    RawSql (..),
+    fromString,
+    toRawSql,
+    intercalate,
+    fromText,
+    space,
+    comma,
+    leftParen,
+    rightParen,
+    equals,
 ) where
 
 import qualified Data.Text as T

src/Orville/SQLite/SqlMarshaller.hs

@@ -3,27 +3,27 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
-module Orville.SQLite.SqlMarshaller
-  ( SqlMarshaller
-  , FieldInfo (..)
-  , marshallField
-  , marshallReadOnlyField
-  , marshallMaybe
-  , marshallerFieldInfo
-  , marshallerDerivedColumns
-  , marshallerEncodeWrite
-  , marshallerDecodeRow
+module Orville.SQLite.SqlMarshaller (
+    SqlMarshaller,
+    FieldInfo (..),
+    marshallField,
+    marshallReadOnlyField,
+    marshallMaybe,
+    marshallerFieldInfo,
+    marshallerDerivedColumns,
+    marshallerEncodeWrite,
+    marshallerDecodeRow,
 ) where
 
 import qualified Database.SQLite3 as SQLite3
-import Orville.SQLite.FieldDefinition
-  ( FieldDefinition (..)
-  , Nullability (..)
-  , fieldColumnName
-  , fieldToSqlValue
-  , fieldFromSqlValue
-  , fieldIsNullable
-  , fieldSqlTypeName
+import Orville.SQLite.FieldDefinition (
+    FieldDefinition (..),
+    Nullability (..),
+    fieldColumnName,
+    fieldFromSqlValue,
+    fieldIsNullable,
+    fieldSqlTypeName,
+    fieldToSqlValue,
  )
 
 data FieldInfo = FieldInfo

src/Orville/SQLite/SqlType.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE LambdaCase #-}
 
-module Orville.SQLite.SqlType
-  ( SqlType (..)
-  , integerType
-  , textType
-  , realType
-  , blobType
-  , convertSqlType
+module Orville.SQLite.SqlType (
+    SqlType (..),
+    integerType,
+    textType,
+    realType,
+    blobType,
+    convertSqlType,
 ) where
 
 import qualified Data.ByteString as BS

src/Orville/SQLite/TableDefinition.hs

@@ -2,19 +2,19 @@
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
-module Orville.SQLite.TableDefinition
-  ( PrimaryKey (..)
-  , primaryKey
-  , TableDefinition (..)
-  , mkTableDefinition
-  , mkTableDefinitionWithoutKey
+module Orville.SQLite.TableDefinition (
+    PrimaryKey (..),
+    primaryKey,
+    TableDefinition (..),
+    mkTableDefinition,
+    mkTableDefinitionWithoutKey,
 ) where
 
-import Orville.SQLite.FieldDefinition
-  ( FieldDefinition
-  , Nullability (..)
-  , integerField
-  , convertField
+import Orville.SQLite.FieldDefinition (
+    FieldDefinition,
+    Nullability (..),
+    convertField,
+    integerField,
  )
 import Orville.SQLite.SqlMarshaller (SqlMarshaller)
 

stack.yaml.lock

@@ -0,0 +1,19 @@
+# This file was autogenerated by Stack.
+# You should not edit this file by hand.
+# For more information, please see the documentation at:
+#   https://docs.haskellstack.org/en/stable/topics/lock_files
+
+packages:
+- completed:
+    hackage: direct-sqlite-2.3.29@sha256:6ff3969a6eae383c8a9ab093abfee7f7b0ed76dab045c984a1497b7e1d71279d,4180
+    pantry-tree:
+      sha256: 794455a2e32dc749ff32d8907bc51d810f79b963d5e21c42bc8555bc34bbd625
+      size: 770
+  original:
+    hackage: direct-sqlite-2.3.29
+snapshots:
+- completed:
+    sha256: 3c412a7c13dba6d3d808455a458e0776c58b6cf99b8a7961a2f5e55589d6f1d6
+    size: 729011
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/24/43.yaml
+  original: lts-24.43

test/Main.hs

@@ -6,8 +6,8 @@ module Main where
 import Control.Monad.IO.Class (liftIO)
 import Data.Int (Int64)
 import Data.Text (Text)
-import Test.Hspec
 import Orville.SQLite
+import Test.Hspec
 
 data Person = Person
     { personId :: Int64