feat: nix dev shell

Author: diced

.gitignore

@@ -47,4 +47,7 @@ next-env.d.ts
 uploads*/
 *.crt
 *.key
-generated
+generated
+
+# nix dev env
+/.psql_db/

README.md

@@ -198,6 +198,24 @@ Create a pull request on GitHub. If your PR does not pass the action checks, the
 
 Here's how to setup Zipline for development
 
+#### Nix
+
+If you have [Nix](https://nixos.org/) installed, you can use the provided dev shell to get started quickly. Just run:
+
+```bash
+nix develop
+```
+
+This will start a postgres server, and drop you into a shell with the necessary tools installed:
+
+- nodejs
+- corepack
+- git
+- ffmpeg
+- postgres server
+
+After hopping into the dev shell, you can follow the instructions below (skipping the prerequisites) to setup a configuration and start the server.
+
 #### Prerequisites
 
 - nodejs (lts -> 20.x, 22.x)

flake.lock

@@ -0,0 +1,84 @@
+{
+  description = "dev env for zipline";
+
+  inputs = {
+    # node 24.4.1, postgres 17
+    nixpkgs.url = "github:nixos/nixpkgs/b527e89270879aaaf584c41f26b2796be634bc9d";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      flake-utils,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+        };
+
+        nodejs = pkgs.nodejs_24;
+        postgres = pkgs.postgresql;
+        psqlDir = ".psql_db/data";
+
+        psqlUsername = "postgres";
+        psqlPassword = "postgres";
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          name = "zipline-dev";
+
+          buildInputs = [
+            nodejs
+            postgres
+
+            pkgs.git
+            pkgs.corepack
+            pkgs.ffmpeg
+          ];
+
+          shellHook = ''
+            export PGDATA="$PWD/${psqlDir}"
+            export PGUSER="${psqlUsername}"
+            export PGPASSWORD="${psqlPassword}"
+            export PGPORT=5432
+
+            if [ ! -d "$PGDATA" ]; then
+              echo "Initializing PostgreSQL data directory at $PGDATA"
+              initdb -D "$PGDATA" --username="$PGUSER" --pwfile=<(echo "$PGPASSWORD")
+            fi
+
+            # listen on localhost
+            echo "host all all 127.0.0.1/32 password" >> "$PGDATA/pg_hba.conf"
+            echo "host all all ::1/128 password" >> "$PGDATA/pg_hba.conf"
+            sed -i "s/^#\?listen_addresses.*/listen_addresses = 'localhost'/" "$PGDATA/postgresql.conf"
+
+            echo "Starting PostgreSQL..."
+            pg_ctl -D "$PGDATA" -o "-p $PGPORT" -w start
+
+            echo -e "PostgreSQL is ready at postgresql://$PGUSER:$PGPASSWORD@localhost:$PGPORT/postgres\n\n"
+
+            stop_postgres() {
+              echo "Stopping PostgreSQL..."
+              pg_ctl -D "$PGDATA" stop
+            }
+
+            # trap pg to stop on exiting the dev shell
+            trap stop_postgres EXIT
+
+            # use zsh if zsh is available
+            if command -v zsh >/dev/null 2>&1; then
+              zsh
+            else
+              $SHELL
+            fi
+
+            exit
+          '';
+        };
+      }
+    );
+}