add sqlite

.gitignore

···
 admin-setup-token.txt
 package-lock.json
 bun.lock
+*.db*

Cargo.lock

···
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
 [[package]]
+name = "foldhash"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a0d2fde1f7b3d48b8395d5f2de76c18a528bd6a9cdde438df747bfcba3e05d6f"
+
+[[package]]
 name = "foreign-types"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
···
 ]
 
 [[package]]
+name = "futures"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "65bc07b1a8bc7c85c5f2e110c476c7389b4554ba72af57d8445ea63a576b0876"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
 name = "futures-channel"
 version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
···
 checksum = "9e5c1b78ca4aae1ac06c48a526a655760685149f0d465d21f37abfe57ce075c6"
 
 [[package]]
+name = "futures-macro"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "162ee34ebcb7c64a8abebc059ce0fee27c2262618d7b60ed8faf72fef13c3650"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
 name = "futures-sink"
 version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
···
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9fa08315bb612088cc391249efdc3bc77536f16c91f6cf495e6fbe85b20a4a81"
 dependencies = [
+ "futures-channel",
  "futures-core",
  "futures-io",
+ "futures-macro",
  "futures-sink",
  "futures-task",
  "memchr",
···
 
 [[package]]
 name = "hashbrown"
-version = "0.14.5"
+version = "0.15.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
+checksum = "bf151400ff0baff5465007dd2f3e717f3fe502074ca563069ce3a6629d07b289"
 dependencies = [
- "ahash",
  "allocator-api2",
+ "equivalent",
+ "foldhash",
 ]
 
 [[package]]
-name = "hashbrown"
-version = "0.15.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bf151400ff0baff5465007dd2f3e717f3fe502074ca563069ce3a6629d07b289"
-
-[[package]]
 name = "hashlink"
-version = "0.9.1"
+version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ba4ff7128dee98c7dc9794b6a411377e1404dba1c97deb8d1a55297bd25d8af"
+checksum = "7382cf6263419f2d8df38c55d7da83da5c18aef87fc7a7fc1fb1e344edfe14c1"
 dependencies = [
- "hashbrown 0.14.5",
+ "hashbrown",
 ]
 
 [[package]]
···
 checksum = "8c9c992b02b5b4c94ea26e32fe5bccb7aa7d9f390ab5c1221ff895bc7ea8b652"
 dependencies = [
  "equivalent",
- "hashbrown 0.15.2",
+ "hashbrown",
 ]
 
 [[package]]
···
 ]
 
 [[package]]
-name = "minimal-lexical"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
-
-[[package]]
 name = "miniz_oxide"
 version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
···
 ]
 
 [[package]]
-name = "nom"
-version = "7.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
-dependencies = [
- "memchr",
- "minimal-lexical",
-]
-
-[[package]]
 name = "nu-ansi-term"
 version = "0.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
···
  "chrono",
  "clap",
  "dotenv",
+ "futures",
  "jsonwebtoken",
  "lazy_static",
  "mime_guess",
···
 ]
 
 [[package]]
-name = "sqlformat"
-version = "0.2.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7bba3a93db0cc4f7bdece8bb09e77e2e785c20bfebf79eb8340ed80708048790"
-dependencies = [
- "nom",
- "unicode_categories",
-]
-
-[[package]]
 name = "sqlx"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fcfa89bea9500db4a0d038513d7a060566bfc51d46d1c014847049a45cce85e8"
+checksum = "4410e73b3c0d8442c5f99b425d7a435b5ee0ae4167b3196771dd3f7a01be745f"
 dependencies = [
  "sqlx-core",
  "sqlx-macros",
···
 
 [[package]]
 name = "sqlx-core"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d06e2f2bd861719b1f3f0c7dbe1d80c30bf59e76cf019f07d9014ed7eefb8e08"
+checksum = "6a007b6936676aa9ab40207cde35daab0a04b823be8ae004368c0793b96a61e0"
 dependencies = [
- "atoi",
- "byteorder",
  "bytes",
  "chrono",
  "crc",
  "crossbeam-queue",
  "either",
  "event-listener",
- "futures-channel",
  "futures-core",
  "futures-intrusive",
  "futures-io",
  "futures-util",
- "hashbrown 0.14.5",
+ "hashbrown",
  "hashlink",
- "hex",
  "indexmap",
  "log",
  "memchr",
  "native-tls",
  "once_cell",
- "paste",
  "percent-encoding",
  "serde",
  "serde_json",
  "sha2",
  "smallvec",
- "sqlformat",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tokio",
  "tokio-stream",
  "tracing",
  "url",
- "uuid",
 ]
 
 [[package]]
 name = "sqlx-macros"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2f998a9defdbd48ed005a89362bd40dd2117502f15294f61c8d47034107dbbdc"
+checksum = "3112e2ad78643fef903618d78cf0aec1cb3134b019730edb039b69eaf531f310"
 dependencies = [
  "proc-macro2",
  "quote",
···
 
 [[package]]
 name = "sqlx-macros-core"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3d100558134176a2629d46cec0c8891ba0be8910f7896abfdb75ef4ab6f4e7ce"
+checksum = "4e9f90acc5ab146a99bf5061a7eb4976b573f560bc898ef3bf8435448dd5e7ad"
 dependencies = [
  "dotenvy",
  "either",
···
 
 [[package]]
 name = "sqlx-mysql"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "936cac0ab331b14cb3921c62156d913e4c15b74fb6ec0f3146bd4ef6e4fb3c12"
+checksum = "4560278f0e00ce64938540546f59f590d60beee33fffbd3b9cd47851e5fff233"
 dependencies = [
  "atoi",
  "base64 0.22.1",
···
  "smallvec",
  "sqlx-core",
  "stringprep",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
- "uuid",
  "whoami",
 ]
 
 [[package]]
 name = "sqlx-postgres"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9734dbce698c67ecf67c442f768a5e90a49b2a4d61a9f1d59f73874bd4cf0710"
+checksum = "c5b98a57f363ed6764d5b3a12bfedf62f07aa16e1856a7ddc2a0bb190a959613"
 dependencies = [
  "atoi",
  "base64 0.22.1",
···
  "etcetera",
  "futures-channel",
  "futures-core",
- "futures-io",
  "futures-util",
  "hex",
  "hkdf",
···
  "smallvec",
  "sqlx-core",
  "stringprep",
- "thiserror 1.0.69",
+ "thiserror 2.0.11",
  "tracing",
- "uuid",
  "whoami",
 ]
 
 [[package]]
 name = "sqlx-sqlite"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a75b419c3c1b1697833dd927bdc4c6545a620bc1bbafabd44e1efbe9afcd337e"
+checksum = "f85ca71d3a5b24e64e1d08dd8fe36c6c95c339a896cc33068148906784620540"
 dependencies = [
  "atoi",
  "chrono",
···
  "sqlx-core",
  "tracing",
  "url",
- "uuid",
 ]
 
 [[package]]
···
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e70f2a8b45122e719eb623c01822704c4e0907e7e426a05927e1a1cfff5b75d0"
-
-[[package]]
-name = "unicode_categories"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "39ec24b3121d976906ece63c9daad25b85969647682eee313cb5779fdd69e14e"
 
 [[package]]
 name = "untrusted"

Cargo.toml

···
 actix-files = "0.6"
 actix-cors = "0.6"
 tokio = { version = "1.36", features = ["full"] }
-sqlx = { version = "0.8", features = ["runtime-tokio-native-tls", "postgres", "uuid", "chrono"] }
+sqlx = { version = "0.8", features = ["runtime-tokio-native-tls", "postgres", "sqlite", "chrono"] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 anyhow = "1.0"
···
 argon2 = "0.5.3"
 rand = { version = "0.8", features = ["std"] }
 mime_guess = "2.0.5"
+futures = "0.3.31"

migrations/sqlite/20250125000000_init.sql

···
+-- Enable foreign key support
+PRAGMA foreign_keys = ON;
+
+-- Add Migration Version
+CREATE TABLE IF NOT EXISTS _sqlx_migrations (
+    version INTEGER PRIMARY KEY,
+    description TEXT NOT NULL,
+    installed_on TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+-- Create users table
+CREATE TABLE users (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    email VARCHAR(255) NOT NULL UNIQUE,
+    password_hash TEXT NOT NULL
+);
+
+-- Create links table
+CREATE TABLE links (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    original_url TEXT NOT NULL,
+    short_code VARCHAR(8) NOT NULL UNIQUE,
+    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    clicks INTEGER NOT NULL DEFAULT 0,
+    user_id INTEGER,
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
+
+-- Create clicks table
+CREATE TABLE clicks (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    link_id INTEGER,
+    source TEXT,
+    query_source TEXT,
+    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (link_id) REFERENCES links(id)
+);
+
+-- Create indexes
+CREATE INDEX idx_short_code ON links(short_code);
+CREATE INDEX idx_user_id ON links(user_id);
+CREATE INDEX idx_link_id ON clicks(link_id);

src/handlers.rs

···
 use crate::{
     error::AppError,
     models::{
-        AuthResponse, Claims, ClickStats, CreateLink, Link, LoginRequest, RegisterRequest,
-        SourceStats, User, UserResponse,
+        AuthResponse, Claims, ClickStats, CreateLink, DatabasePool, Link, LoginRequest,
+        RegisterRequest, SourceStats, User, UserResponse,
     },
     AppState,
 };
···
 use jsonwebtoken::{encode, EncodingKey, Header};
 use lazy_static::lazy_static;
 use regex::Regex;
+use sqlx::{Postgres, Sqlite};
 
 lazy_static! {
     static ref VALID_CODE_REGEX: Regex = Regex::new(r"^[a-zA-Z0-9_-]{1,32}$").unwrap();
···
     payload: web::Json<CreateLink>,
 ) -> Result<impl Responder, AppError> {
     tracing::debug!("Creating short URL with user_id: {}", user.user_id);
-
     validate_url(&payload.url)?;
 
     let short_code = if let Some(ref custom_code) = payload.custom_code {
         validate_custom_code(custom_code)?;
 
-        tracing::debug!("Checking if custom code {} exists", custom_code);
-        // Check if code is already taken
-        if let Some(_) = sqlx::query_as::<_, Link>("SELECT * FROM links WHERE short_code = $1")
-            .bind(custom_code)
-            .fetch_optional(&state.db)
-            .await?
-        {
+        // Check if code exists using match on pool type
+        let exists = match &state.db {
+            DatabasePool::Postgres(pool) => {
+                sqlx::query_as::<_, Link>("SELECT * FROM links WHERE short_code = $1")
+                    .bind(custom_code)
+                    .fetch_optional(pool)
+                    .await?
+            }
+            DatabasePool::Sqlite(pool) => {
+                sqlx::query_as::<_, Link>("SELECT * FROM links WHERE short_code = ?1")
+                    .bind(custom_code)
+                    .fetch_optional(pool)
+                    .await?
+            }
+        };
+
+        if exists.is_some() {
             return Err(AppError::InvalidInput(
                 "Custom code already taken".to_string(),
             ));
         }
-
         custom_code.clone()
     } else {
         generate_short_code()
     };
 
-    // Start transaction
-    let mut tx = state.db.begin().await?;
+    // Start transaction based on pool type
+    let result = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
 
-    tracing::debug!("Inserting new link with short_code: {}", short_code);
-    let link = sqlx::query_as::<_, Link>(
-        "INSERT INTO links (original_url, short_code, user_id) VALUES ($1, $2, $3) RETURNING *",
-    )
-    .bind(&payload.url)
-    .bind(&short_code)
-    .bind(user.user_id)
-    .fetch_one(&mut *tx)
-    .await?;
+            let link = sqlx::query_as::<_, Link>(
+                "INSERT INTO links (original_url, short_code, user_id) VALUES ($1, $2, $3) RETURNING *"
+            )
+            .bind(&payload.url)
+            .bind(&short_code)
+            .bind(user.user_id)
+            .fetch_one(&mut *tx)
+            .await?;
+
+            if let Some(ref source) = payload.source {
+                sqlx::query("INSERT INTO clicks (link_id, source) VALUES ($1, $2)")
+                    .bind(link.id)
+                    .bind(source)
+                    .execute(&mut *tx)
+                    .await?;
+            }
+
+            tx.commit().await?;
+            link
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
 
-    if let Some(ref source) = payload.source {
-        tracing::debug!("Adding click source: {}", source);
-        sqlx::query("INSERT INTO clicks (link_id, source) VALUES ($1, $2)")
-            .bind(link.id)
-            .bind(source)
-            .execute(&mut *tx)
+            let link = sqlx::query_as::<_, Link>(
+                "INSERT INTO links (original_url, short_code, user_id) VALUES (?1, ?2, ?3) RETURNING *"
+            )
+            .bind(&payload.url)
+            .bind(&short_code)
+            .bind(user.user_id)
+            .fetch_one(&mut *tx)
             .await?;
-    }
 
-    tx.commit().await?;
-    Ok(HttpResponse::Created().json(link))
+            if let Some(ref source) = payload.source {
+                sqlx::query("INSERT INTO clicks (link_id, source) VALUES (?1, ?2)")
+                    .bind(link.id)
+                    .bind(source)
+                    .execute(&mut *tx)
+                    .await?;
+            }
+
+            tx.commit().await?;
+            link
+        }
+    };
+
+    Ok(HttpResponse::Created().json(result))
 }
 
 fn validate_custom_code(code: &str) -> Result<(), AppError> {
···
         .and_then(|q| web::Query::<std::collections::HashMap<String, String>>::from_query(q).ok())
         .and_then(|params| params.get("source").cloned());
 
-    let mut tx = state.db.begin().await?;
-
-    let link = sqlx::query_as::<_, Link>(
-        "UPDATE links SET clicks = clicks + 1 WHERE short_code = $1 RETURNING *",
-    )
-    .bind(&short_code)
-    .fetch_optional(&mut *tx)
-    .await?;
+    let link = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<_, Link>(
+                "UPDATE links SET clicks = clicks + 1 WHERE short_code = $1 RETURNING *",
+            )
+            .bind(&short_code)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<_, Link>(
+                "UPDATE links SET clicks = clicks + 1 WHERE short_code = ?1 RETURNING *",
+            )
+            .bind(&short_code)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+    };
 
     match link {
         Some(link) => {
-            // Record click with both user agent and query source
-            let user_agent = req
-                .headers()
-                .get("user-agent")
-                .and_then(|h| h.to_str().ok())
-                .unwrap_or("unknown")
-                .to_string();
+            // Handle click recording based on database type
+            match &state.db {
+                DatabasePool::Postgres(pool) => {
+                    let mut tx = pool.begin().await?;
+                    let user_agent = req
+                        .headers()
+                        .get("user-agent")
+                        .and_then(|h| h.to_str().ok())
+                        .unwrap_or("unknown")
+                        .to_string();
+
+                    sqlx::query(
+                        "INSERT INTO clicks (link_id, source, query_source) VALUES ($1, $2, $3)",
+                    )
+                    .bind(link.id)
+                    .bind(user_agent)
+                    .bind(query_source)
+                    .execute(&mut *tx)
+                    .await?;
+
+                    tx.commit().await?;
+                }
+                DatabasePool::Sqlite(pool) => {
+                    let mut tx = pool.begin().await?;
+                    let user_agent = req
+                        .headers()
+                        .get("user-agent")
+                        .and_then(|h| h.to_str().ok())
+                        .unwrap_or("unknown")
+                        .to_string();
 
-            sqlx::query("INSERT INTO clicks (link_id, source, query_source) VALUES ($1, $2, $3)")
-                .bind(link.id)
-                .bind(user_agent)
-                .bind(query_source)
-                .execute(&mut *tx)
-                .await?;
+                    sqlx::query(
+                        "INSERT INTO clicks (link_id, source, query_source) VALUES (?1, ?2, ?3)",
+                    )
+                    .bind(link.id)
+                    .bind(user_agent)
+                    .bind(query_source)
+                    .execute(&mut *tx)
+                    .await?;
 
-            tx.commit().await?;
+                    tx.commit().await?;
+                }
+            };
 
             Ok(HttpResponse::TemporaryRedirect()
                 .append_header(("Location", link.original_url))
···
     state: web::Data<AppState>,
     user: AuthenticatedUser,
 ) -> Result<impl Responder, AppError> {
-    let links = sqlx::query_as::<_, Link>(
-        "SELECT * FROM links WHERE user_id = $1 ORDER BY created_at DESC",
-    )
-    .bind(user.user_id)
-    .fetch_all(&state.db)
-    .await?;
+    let links = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            sqlx::query_as::<_, Link>(
+                "SELECT * FROM links WHERE user_id = $1 ORDER BY created_at DESC",
+            )
+            .bind(user.user_id)
+            .fetch_all(pool)
+            .await?
+        }
+        DatabasePool::Sqlite(pool) => {
+            sqlx::query_as::<_, Link>(
+                "SELECT * FROM links WHERE user_id = ?1 ORDER BY created_at DESC",
+            )
+            .bind(user.user_id)
+            .fetch_all(pool)
+            .await?
+        }
+    };
 
     Ok(HttpResponse::Ok().json(links))
 }
 
 pub async fn health_check(state: web::Data<AppState>) -> impl Responder {
-    match sqlx::query("SELECT 1").execute(&state.db).await {
-        Ok(_) => HttpResponse::Ok().json("Healthy"),
-        Err(_) => HttpResponse::ServiceUnavailable().json("Database unavailable"),
+    let is_healthy = match &state.db {
+        DatabasePool::Postgres(pool) => sqlx::query("SELECT 1").execute(pool).await.is_ok(),
+        DatabasePool::Sqlite(pool) => sqlx::query("SELECT 1").execute(pool).await.is_ok(),
+    };
+
+    if is_healthy {
+        HttpResponse::Ok().json("Healthy")
+    } else {
+        HttpResponse::ServiceUnavailable().json("Database unavailable")
     }
 }
 
···
     payload: web::Json<RegisterRequest>,
 ) -> Result<impl Responder, AppError> {
     // Check if any users exist
-    let user_count = sqlx::query!("SELECT COUNT(*) as count FROM users")
-        .fetch_one(&state.db)
-        .await?
-        .count
-        .unwrap_or(0);
+    let user_count = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let count = sqlx::query_as::<Postgres, (i64,)>("SELECT COUNT(*)::bigint FROM users")
+                .fetch_one(&mut *tx)
+                .await?
+                .0;
+            tx.commit().await?;
+            count
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let count = sqlx::query_as::<Sqlite, (i64,)>("SELECT COUNT(*) FROM users")
+                .fetch_one(&mut *tx)
+                .await?
+                .0;
+            tx.commit().await?;
+            count
+        }
+    };
 
     // If users exist, registration is closed - no exceptions
     if user_count > 0 {
···
     }
 
     // Check if email already exists
-    let exists = sqlx::query!("SELECT id FROM users WHERE email = $1", payload.email)
-        .fetch_optional(&state.db)
-        .await?;
+    let exists = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let exists =
+                sqlx::query_as::<Postgres, (i32,)>("SELECT id FROM users WHERE email = $1")
+                    .bind(&payload.email)
+                    .fetch_optional(&mut *tx)
+                    .await?;
+            tx.commit().await?;
+            exists
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let exists = sqlx::query_as::<Sqlite, (i32,)>("SELECT id FROM users WHERE email = ?")
+                .bind(&payload.email)
+                .fetch_optional(&mut *tx)
+                .await?;
+            tx.commit().await?;
+            exists
+        }
+    };
 
     if exists.is_some() {
         return Err(AppError::Auth("Email already registered".to_string()));
···
         .map_err(|e| AppError::Auth(e.to_string()))?
         .to_string();
 
-    let user = sqlx::query_as!(
-        User,
-        "INSERT INTO users (email, password_hash) VALUES ($1, $2) RETURNING *",
-        payload.email,
-        password_hash
-    )
-    .fetch_one(&state.db)
-    .await?;
+    // Insert new user
+    let user = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let user = sqlx::query_as::<Postgres, User>(
+                "INSERT INTO users (email, password_hash) VALUES ($1, $2) RETURNING *",
+            )
+            .bind(&payload.email)
+            .bind(&password_hash)
+            .fetch_one(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            user
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let user = sqlx::query_as::<Sqlite, User>(
+                "INSERT INTO users (email, password_hash) VALUES (?, ?) RETURNING *",
+            )
+            .bind(&payload.email)
+            .bind(&password_hash)
+            .fetch_one(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            user
+        }
+    };
 
     let claims = Claims::new(user.id);
     let secret = std::env::var("JWT_SECRET").unwrap_or_else(|_| "default_secret".to_string());
···
     state: web::Data<AppState>,
     payload: web::Json<LoginRequest>,
 ) -> Result<impl Responder, AppError> {
-    let user = sqlx::query_as!(User, "SELECT * FROM users WHERE email = $1", payload.email)
-        .fetch_optional(&state.db)
-        .await?
-        .ok_or_else(|| AppError::Auth("Invalid credentials".to_string()))?;
+    let user = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let user = sqlx::query_as::<Postgres, User>("SELECT * FROM users WHERE email = $1")
+                .bind(&payload.email)
+                .fetch_optional(&mut *tx)
+                .await?;
+            tx.commit().await?;
+            user
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let user = sqlx::query_as::<Sqlite, User>("SELECT * FROM users WHERE email = ?")
+                .bind(&payload.email)
+                .fetch_optional(&mut *tx)
+                .await?;
+            tx.commit().await?;
+            user
+        }
+    }
+    .ok_or_else(|| AppError::Auth("Invalid credentials".to_string()))?;
 
     let argon2 = Argon2::default();
     let parsed_hash =
···
 ) -> Result<impl Responder, AppError> {
     let link_id = path.into_inner();
 
-    // Start transaction
-    let mut tx = state.db.begin().await?;
+    match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
 
-    // Verify the link belongs to the user
-    let link = sqlx::query!(
-        "SELECT id FROM links WHERE id = $1 AND user_id = $2",
-        link_id,
-        user.user_id
-    )
-    .fetch_optional(&mut *tx)
-    .await?;
+            // Verify the link belongs to the user
+            let link = sqlx::query_as::<Postgres, (i32,)>(
+                "SELECT id FROM links WHERE id = $1 AND user_id = $2",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
 
-    if link.is_none() {
-        return Err(AppError::NotFound);
-    }
+            if link.is_none() {
+                return Err(AppError::NotFound);
+            }
 
-    // Delete associated clicks first due to foreign key constraint
-    sqlx::query!("DELETE FROM clicks WHERE link_id = $1", link_id)
-        .execute(&mut *tx)
-        .await?;
+            // Delete associated clicks first due to foreign key constraint
+            sqlx::query("DELETE FROM clicks WHERE link_id = $1")
+                .bind(link_id)
+                .execute(&mut *tx)
+                .await?;
 
-    // Delete the link
-    sqlx::query!("DELETE FROM links WHERE id = $1", link_id)
-        .execute(&mut *tx)
-        .await?;
+            // Delete the link
+            sqlx::query("DELETE FROM links WHERE id = $1")
+                .bind(link_id)
+                .execute(&mut *tx)
+                .await?;
+
+            tx.commit().await?;
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+
+            // Verify the link belongs to the user
+            let link = sqlx::query_as::<Sqlite, (i32,)>(
+                "SELECT id FROM links WHERE id = ? AND user_id = ?",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
+
+            if link.is_none() {
+                return Err(AppError::NotFound);
+            }
+
+            // Delete associated clicks first due to foreign key constraint
+            sqlx::query("DELETE FROM clicks WHERE link_id = ?")
+                .bind(link_id)
+                .execute(&mut *tx)
+                .await?;
+
+            // Delete the link
+            sqlx::query("DELETE FROM links WHERE id = ?")
+                .bind(link_id)
+                .execute(&mut *tx)
+                .await?;
 
-    tx.commit().await?;
+            tx.commit().await?;
+        }
+    }
 
     Ok(HttpResponse::NoContent().finish())
 }
···
     let link_id = path.into_inner();
 
     // Verify the link belongs to the user
-    let link = sqlx::query!(
-        "SELECT id FROM links WHERE id = $1 AND user_id = $2",
-        link_id,
-        user.user_id
-    )
-    .fetch_optional(&state.db)
-    .await?;
+    let link = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<Postgres, (i32,)>(
+                "SELECT id FROM links WHERE id = $1 AND user_id = $2",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<Sqlite, (i32,)>(
+                "SELECT id FROM links WHERE id = ? AND user_id = ?",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+    };
 
     if link.is_none() {
         return Err(AppError::NotFound);
     }
 
-    let clicks = sqlx::query_as!(
-        ClickStats,
-        r#"
-        SELECT 
-            DATE(created_at)::date as "date!",
-            COUNT(*)::bigint as "clicks!"
-        FROM clicks
-        WHERE link_id = $1
-        GROUP BY DATE(created_at)
-        ORDER BY DATE(created_at) ASC  -- Changed from DESC to ASC
-        LIMIT 30
-        "#,
-        link_id
-    )
-    .fetch_all(&state.db)
-    .await?;
+    let clicks = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            sqlx::query_as::<Postgres, ClickStats>(
+                r#"
+                SELECT 
+                    DATE(created_at)::date as "date!",
+                    COUNT(*)::bigint as "clicks!"
+                FROM clicks
+                WHERE link_id = $1
+                GROUP BY DATE(created_at)
+                ORDER BY DATE(created_at) ASC
+                LIMIT 30
+                "#,
+            )
+            .bind(link_id)
+            .fetch_all(pool)
+            .await?
+        }
+        DatabasePool::Sqlite(pool) => {
+            sqlx::query_as::<Sqlite, ClickStats>(
+                r#"
+                SELECT 
+                    DATE(created_at) as "date!",
+                    COUNT(*) as "clicks!"
+                FROM clicks
+                WHERE link_id = ?
+                GROUP BY DATE(created_at)
+                ORDER BY DATE(created_at) ASC
+                LIMIT 30
+                "#,
+            )
+            .bind(link_id)
+            .fetch_all(pool)
+            .await?
+        }
+    };
 
     Ok(HttpResponse::Ok().json(clicks))
 }
···
     let link_id = path.into_inner();
 
     // Verify the link belongs to the user
-    let link = sqlx::query!(
-        "SELECT id FROM links WHERE id = $1 AND user_id = $2",
-        link_id,
-        user.user_id
-    )
-    .fetch_optional(&state.db)
-    .await?;
+    let link = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<Postgres, (i32,)>(
+                "SELECT id FROM links WHERE id = $1 AND user_id = $2",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let link = sqlx::query_as::<Sqlite, (i32,)>(
+                "SELECT id FROM links WHERE id = ? AND user_id = ?",
+            )
+            .bind(link_id)
+            .bind(user.user_id)
+            .fetch_optional(&mut *tx)
+            .await?;
+            tx.commit().await?;
+            link
+        }
+    };
 
     if link.is_none() {
         return Err(AppError::NotFound);
     }
 
-    let sources = sqlx::query_as!(
-        SourceStats,
-        r#"
-        SELECT 
-            query_source as "source!",
-            COUNT(*)::bigint as "count!"
-        FROM clicks
-        WHERE link_id = $1
-            AND query_source IS NOT NULL
-            AND query_source != ''
-        GROUP BY query_source
-        ORDER BY COUNT(*) DESC
-        LIMIT 10
-        "#,
-        link_id
-    )
-    .fetch_all(&state.db)
-    .await?;
+    let sources = match &state.db {
+        DatabasePool::Postgres(pool) => {
+            sqlx::query_as::<Postgres, SourceStats>(
+                r#"
+                SELECT 
+                    query_source as "source!",
+                    COUNT(*)::bigint as "count!"
+                FROM clicks
+                WHERE link_id = $1
+                    AND query_source IS NOT NULL
+                    AND query_source != ''
+                GROUP BY query_source
+                ORDER BY COUNT(*) DESC
+                LIMIT 10
+                "#,
+            )
+            .bind(link_id)
+            .fetch_all(pool)
+            .await?
+        }
+        DatabasePool::Sqlite(pool) => {
+            sqlx::query_as::<Sqlite, SourceStats>(
+                r#"
+                SELECT 
+                    query_source as "source!",
+                    COUNT(*) as "count!"
+                FROM clicks
+                WHERE link_id = ?
+                    AND query_source IS NOT NULL
+                    AND query_source != ''
+                GROUP BY query_source
+                ORDER BY COUNT(*) DESC
+                LIMIT 10
+                "#,
+            )
+            .bind(link_id)
+            .fetch_all(pool)
+            .await?
+        }
+    };
 
     Ok(HttpResponse::Ok().json(sources))
 }

src/lib.rs

···
+use anyhow::Result;
 use rand::Rng;
-use sqlx::PgPool;
+use sqlx::migrate::MigrateDatabase;
+use sqlx::postgres::PgPoolOptions;
+use sqlx::{Postgres, Sqlite};
 use std::fs::File;
 use std::io::Write;
 use tracing::info;
 
+use models::DatabasePool;
+
 pub mod auth;
 pub mod error;
 pub mod handlers;
···
 
 #[derive(Clone)]
 pub struct AppState {
-    pub db: PgPool,
+    pub db: DatabasePool,
     pub admin_token: Option<String>,
 }
 
-pub async fn check_and_generate_admin_token(pool: &sqlx::PgPool) -> anyhow::Result<Option<String>> {
+pub async fn create_db_pool() -> Result<DatabasePool> {
+    let database_url = std::env::var("DATABASE_URL").ok();
+
+    match database_url {
+        Some(url) if url.starts_with("postgres://") => {
+            info!("Using PostgreSQL database");
+            let pool = PgPoolOptions::new()
+                .max_connections(5)
+                .acquire_timeout(std::time::Duration::from_secs(3))
+                .connect(&url)
+                .await?;
+
+            Ok(DatabasePool::Postgres(pool))
+        }
+        _ => {
+            info!("No PostgreSQL connection string found, using SQLite");
+
+            // Create a data directory if it doesn't exist
+            let data_dir = std::path::Path::new("data");
+            if !data_dir.exists() {
+                std::fs::create_dir_all(data_dir)?;
+            }
+
+            let db_path = data_dir.join("simplelink.db");
+            let sqlite_url = format!("sqlite://{}", db_path.display());
+
+            // Check if database exists and create it if it doesn't
+            if !Sqlite::database_exists(&sqlite_url).await.unwrap_or(false) {
+                info!("Creating new SQLite database at {}", db_path.display());
+                Sqlite::create_database(&sqlite_url).await?;
+                info!("Database created successfully");
+            } else {
+                info!("Database already exists");
+            }
+
+            let pool = sqlx::sqlite::SqlitePoolOptions::new()
+                .max_connections(5)
+                .connect(&sqlite_url)
+                .await?;
+
+            Ok(DatabasePool::Sqlite(pool))
+        }
+    }
+}
+
+pub async fn run_migrations(pool: &DatabasePool) -> Result<()> {
+    match pool {
+        DatabasePool::Postgres(pool) => {
+            // Use the root migrations directory for postgres
+            sqlx::migrate!().run(pool).await?;
+        }
+        DatabasePool::Sqlite(pool) => {
+            sqlx::migrate!("./migrations/sqlite").run(pool).await?;
+        }
+    }
+    Ok(())
+}
+
+pub async fn check_and_generate_admin_token(db: &DatabasePool) -> anyhow::Result<Option<String>> {
     // Check if any users exist
-    let user_count = sqlx::query!("SELECT COUNT(*) as count FROM users")
-        .fetch_one(pool)
-        .await?
-        .count
-        .unwrap_or(0);
+    let user_count = match db {
+        DatabasePool::Postgres(pool) => {
+            let mut tx = pool.begin().await?;
+            let count = sqlx::query_as::<Postgres, (i64,)>("SELECT COUNT(*)::bigint FROM users")
+                .fetch_one(&mut *tx)
+                .await?
+                .0;
+            tx.commit().await?;
+            count
+        }
+        DatabasePool::Sqlite(pool) => {
+            let mut tx = pool.begin().await?;
+            let count = sqlx::query_as::<Sqlite, (i64,)>("SELECT COUNT(*) FROM users")
+                .fetch_one(&mut *tx)
+                .await?
+                .0;
+            tx.commit().await?;
+            count
+        }
+    };
 
     if user_count == 0 {
         // Generate a random token using simple characters

src/main.rs

···
 use anyhow::Result;
 use rust_embed::RustEmbed;
 use simplelink::check_and_generate_admin_token;
+use simplelink::{create_db_pool, run_migrations};
 use simplelink::{handlers, AppState};
-use sqlx::postgres::PgPoolOptions;
 use tracing::info;
 
 #[derive(RustEmbed)]
···
     // Initialize logging
     tracing_subscriber::fmt::init();
 
-    // Database connection string from environment
-    let database_url = std::env::var("DATABASE_URL").expect("DATABASE_URL must be set");
-
     // Create database connection pool
-    let pool = PgPoolOptions::new()
-        .max_connections(5)
-        .acquire_timeout(std::time::Duration::from_secs(3))
-        .connect(&database_url)
-        .await?;
-
-    // Run database migrations
-    sqlx::migrate!("./migrations").run(&pool).await?;
+    let pool = create_db_pool().await?;
+    run_migrations(&pool).await?;
 
     let admin_token = check_and_generate_admin_token(&pool).await?;
 

src/models.rs

···
-use std::time::{SystemTime, UNIX_EPOCH};
-
+use anyhow::Result;
 use chrono::NaiveDate;
+use futures::future::BoxFuture;
 use serde::{Deserialize, Serialize};
+use sqlx::postgres::PgRow;
+use sqlx::sqlite::SqliteRow;
 use sqlx::FromRow;
+use sqlx::Pool;
+use sqlx::Postgres;
+use sqlx::Sqlite;
+use sqlx::Transaction;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+#[derive(Clone)]
+pub enum DatabasePool {
+    Postgres(Pool<Postgres>),
+    Sqlite(Pool<Sqlite>),
+}
+
+impl DatabasePool {
+    pub async fn begin(&self) -> Result<Box<dyn std::any::Any + Send>> {
+        match self {
+            DatabasePool::Postgres(pool) => Ok(Box::new(pool.begin().await?)),
+            DatabasePool::Sqlite(pool) => Ok(Box::new(pool.begin().await?)),
+        }
+    }
+
+    pub async fn fetch_optional<T>(&self, pg_query: &str, sqlite_query: &str) -> Result<Option<T>>
+    where
+        T: for<'r> FromRow<'r, PgRow> + for<'r> FromRow<'r, SqliteRow> + Send + Sync + Unpin,
+    {
+        match self {
+            DatabasePool::Postgres(pool) => {
+                Ok(sqlx::query_as(pg_query).fetch_optional(pool).await?)
+            }
+            DatabasePool::Sqlite(pool) => {
+                Ok(sqlx::query_as(sqlite_query).fetch_optional(pool).await?)
+            }
+        }
+    }
+
+    pub async fn execute(&self, pg_query: &str, sqlite_query: &str) -> Result<()> {
+        match self {
+            DatabasePool::Postgres(pool) => {
+                sqlx::query(pg_query).execute(pool).await?;
+                Ok(())
+            }
+            DatabasePool::Sqlite(pool) => {
+                sqlx::query(sqlite_query).execute(pool).await?;
+                Ok(())
+            }
+        }
+    }
+
+    pub async fn transaction<'a, F, R>(&'a self, f: F) -> Result<R>
+    where
+        F: for<'c> Fn(&'c mut Transaction<'_, Postgres>) -> BoxFuture<'c, Result<R>>
+            + for<'c> Fn(&'c mut Transaction<'_, Sqlite>) -> BoxFuture<'c, Result<R>>
+            + Copy,
+        R: Send + 'static,
+    {
+        match self {
+            DatabasePool::Postgres(pool) => {
+                let mut tx = pool.begin().await?;
+                let result = f(&mut tx).await?;
+                tx.commit().await?;
+                Ok(result)
+            }
+            DatabasePool::Sqlite(pool) => {
+                let mut tx = pool.begin().await?;
+                let result = f(&mut tx).await?;
+                tx.commit().await?;
+                Ok(result)
+            }
+        }
+    }
+}
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct Claims {