diff --git a/assembler.bash b/assembler.bash
new file mode 100644
index 0000000..0b5e201
--- /dev/null
+++ b/assembler.bash
@@ -0,0 +1,74 @@
+# this is the basic structure for an S/370 assembler in bash
+# (c) 2024 by moshix
+# can be easily extended
+# works as fast as a python program
+# v 0.1 humble beginnings
+# v 0.2 first few instructions
+# v 0.3 CSECT and DSECT 
+#!/bin/bash
+
+# Instruction set (extendable)
+declare -A INSTRUCTIONS=(
+    ["L"]="58"    # Load
+    ["ST"]="50"   # Store
+    ["A"]="5A"    # Add
+    ["S"]="5B"    # Subtract
+    ["M"]="5C"    # Multiply
+    ["D"]="5D"    # Divide
+    ["B"]="47"    # Branch
+    ["BZ"]="47"   # Branch on Zero
+    ["BN"]="47"   # Branch on Negative
+    ["MVI"]="92"  # Move Immediate
+    # Add more instructions here as needed
+)
+
+# Function to assemble a single line of S/370 assembly code
+assemble_line() {
+    local line="$1"
+    local instruction=$(echo "$line" | awk '{print $1}')
+    local operands=$(echo "$line" | awk '{print $2}')
+
+    # Handle special directives
+    case "$instruction" in
+        "USING")
+            echo "Processing USING directive: $operands"
+            ;;
+        "CSECT")
+            echo "Processing CSECT directive: $operands"
+            ;;
+        "DSECT")
+            echo "Processing DSECT directive: $operands"
+            ;;
+        *)
+            # Check if the instruction exists
+            if [[ -n "${INSTRUCTIONS[$instruction]}" ]]; then
+                local opcode="${INSTRUCTIONS[$instruction]}"
+                echo "$opcode $operands"
+            else
+                echo "Error: Unknown instruction '$instruction'" >&2
+            fi
+            ;;
+    esac
+}
+
+# Main function to assemble a file
+assemble_file() {
+    local file="$1"
+
+    if [[ ! -f "$file" ]]; then
+        echo "Error: File '$file' not found." >&2
+        return 1
+    fi
+
+    while IFS= read -r line; do
+        assemble_line "$line"
+    done < "$file"
+}
+
+# Check for input file argument
+if [[ $# -ne 1 ]]; then
+    echo "Usage: $0 <assembly_file>" >&2
+    exit 1
+fi
+
+assemble_file "$1"