diff --git a/TODO.md b/TODO.md
index ca55009..8b6f6af 100644
--- a/TODO.md
+++ b/TODO.md
@@ -32,8 +32,18 @@
 - [X] Add a Share button to the formula list. It will export the array string literal of the formula with the units from Corpus.withDependencies().
 - [X] Replace flutter-markdown with flutter-markdown-plus
 - [X] Heron's formula: investigate why a=3, b=40, c=5 yields NaN. Root cause: input values don't form a valid triangle (violate triangle inequality: 3+5=8 is not > 40). Added documentation note to the formula description.
-- [R] Refactor ./assets/formulas d4rt files:
-  - [R] Pretty print files as dart literals (like JSON, but allow raw strings r"""like this""")
-  - [R] Ensure there is no formula duplicates. If necesary, move or delete the formula in file formulas.d4rt
-  - [R] defaultCorpus must load all formula files
-- [ ] Investigate starup time when there is no previous database and corpus is loaded from assets.
+- [X] Refactor ./assets/formulas d4rt files:
+  - [X] Pretty print files as dart literals (like JSON, but allow raw strings r"""like this""")
+  - [X] Ensure there is no formula duplicates. If necesary, move or delete the formula in file formulas.d4rt
+  - [X] defaultCorpus must load all formula files
+- [X] Create a formula in ./assets/formulas/networking.d4art: input is a string with ip address and mask, output is ip subnet of this address and broadcast address.
+- [R] Develop a new screen that edits a formula in ./lib/ai directory:
+  - [R] FormulaEditor initializes with a Formula
+  - [R] A textfield allows editing the "name" of the formula
+  - [R] A text area allows editing the "description". A button pops up a preview of the markdown.
+  - [R] There is one row per input variable. The "name" is a textfield. A first drop down allows to select the base unit, and a second dropdown is populated with all derived units of the selected base unit, and the base unit. The unit of the input variable is the derived unit.
+  - [R] Each input variable can be deleted with a button
+  - [R] A button after the inputs variables allows to insert a new input variable
+  - [R] There is one row for the ouput variable, similar to the row for the input variable
+  - [R] d4rtCode is a text area with dart syntax highligthing
+  - [R] At the botton, a button allows to test the edited Formula, launching a FormulaScreen
diff --git a/assets/formula-element-format.md b/assets/formula-element-format.md
new file mode 100644
index 0000000..3eb8710
--- /dev/null
+++ b/assets/formula-element-format.md
@@ -0,0 +1,507 @@
+# Formula and Unit File Format Guide
+
+This document describes the format for contributing formulas and units to the d4rt_formulas project. It is intended for formula contributors and developers.
+
+---
+
+## Table of Contents
+
+1. [Overview](#overview)
+2. [Formula Files](#formula-files)
+3. [Unit Files](#unit-files)
+4. [Writing Descriptions](#writing-descriptions)
+5. [Best Practices](#best-practices)
+6. [Examples](#examples)
+
+---
+
+## Overview
+
+The project uses two types of asset files:
+
+| File Type    | Location           | Extension     | Format                          |
+|--------------|--------------------|---------------|---------------------------------|
+| **Formulas** | `assets/formulas/` | `.d4rt`       | Dart array literals (JSON-like) |
+| **Units**    | `assets/units/`    | `.d4rt.units` | Dart array literals (JSON-like) |
+
+Both formats use Dart set/array literals with map entries. Files are parsed at runtime to populate the formula calculator.
+
+---
+
+## Formula Files
+
+### File Structure
+
+Formula files are organized by topic (e.g., `geometry.d4rt`, `electromagnetism.d4rt`). Each file contains a Dart array literal with formula objects:
+
+```dart
+[
+  {
+    "name": "Formula Name",
+    "description": r"""Markdown description with LaTeX""",
+    "input": [
+      {"name": "variable1", "unit": "unit_name"},
+      {"name": "variable2", "unit": "unit_name"}
+    ],
+    "output": {"name": "result", "unit": "unit_name"},
+    "d4rtCode": "result = expression;",
+    "tags": ["tag1", "tag2"]
+  },
+  // More formulas...
+]
+```
+
+### Formula Object Fields
+
+| Field         | Type   | Required | Description                                                                              |
+|---------------|--------|----------|------------------------------------------------------------------------------------------|
+| `name`        | String | Yes      | Human-readable formula name                                                              |
+| `description` | String | Yes      | Markdown description with LaTeX math (see [Writing Descriptions](#writing-descriptions)) |
+| `input`       | Array  | Yes      | List of input variables with their units                                                 |
+| `output`      | Object | Yes      | Output variable name and unit                                                            |
+| `d4rtCode`    | String | Yes      | Dart code that computes the result                                                       |
+| `tags`        | Array  | Yes      | Categorization tags for search/filter                                                    |
+
+### Input/Output Format
+
+**Input variables:**
+```dart
+"input": [
+  {"name": "m", "unit": "kilogram"},
+  {"name": "a", "unit": "meters per square second"}
+]
+```
+
+**Output variable:**
+```dart
+"output": {"name": "F", "unit": "newton"}
+```
+
+### Unit Names
+
+Unit names must match entries in the `assets/units/` directory. Use the full unit name (lowercase), not the symbol:
+
+| Correct               | Incorrect |
+|-----------------------|-----------|
+| `"meter"`             | `"m"`     |
+| `"kilogram"`          | `"kg"`    |
+| `"meters per second"` | `"m/s"`   |
+| `"square meter"`      | `"m²"`    |
+
+### Dart Code (`d4rtCode`)
+
+The `d4rtCode` field contains valid Dart code that:
+- Uses input variable names directly
+- Assigns the result to the output variable name
+- Can use Dart's `math` library functions (`sin`, `cos`, `sqrt`, `pow`, `pi`, etc.)
+
+**Simple formula:**
+```dart
+"d4rtCode": "F = m * a;"
+```
+
+**Multi-line formula:**
+```dart
+"d4rtCode": """
+   var radians = angle * (pi / 180);
+   result = sin(radians);
+"""
+```
+
+**With validation:**
+```dart
+"d4rtCode": """
+   if (a + b < c) {
+      signal("Invalid triangle: sides do not satisfy triangle inequality");
+   }
+   var s = (a + b + c) / 2;
+   A = sqrt(s * (s - a) * (s - b) * (s - c));
+"""
+```
+
+---
+
+## Unit Files
+
+### File Structure
+
+Unit files define units of measurement organized by category (e.g., `distance.d4rt.units`, `force.d4rt.units`). Each file contains a Dart array literal with unit objects:
+
+```dart
+[
+  {"name": "meter", "symbol": "m", "isBase": true},
+  {"name": "kilometer", "symbol": "km", "baseUnit": "meter", "factor": 1000},
+  // More units...
+]
+```
+
+### Unit Object Fields
+
+| Field      | Type    | Required    | Description                                                         |
+|------------|---------|-------------|---------------------------------------------------------------------|
+| `name`     | String  | Yes         | Full unit name (lowercase)                                          |
+| `symbol`   | String  | Yes         | Unit symbol for display                                             |
+| `isBase`   | Boolean | Conditional | `true` if this is a base unit (no conversion needed)                |
+| `baseUnit` | String  | Conditional | Name of the base unit for conversion                                |
+| `factor`   | Number  | Conditional | Multiplication factor to convert to base unit                       |
+| `toBase`   | String  | Conditional | Expression/code to convert to base unit (for complex conversions)   |
+| `fromBase` | String  | Conditional | Expression/code to convert from base unit (for complex conversions) |
+
+### Base Units vs Derived Units
+
+**Base units** define the reference for a category:
+```dart
+{"name": "meter", "symbol": "m", "isBase": true}
+{"name": "newton", "symbol": "N", "isBase": true}
+{"name": "joule", "symbol": "J", "isBase": true}
+{"name": "Kelvin", "symbol": "K", "isBase": true}
+```
+
+**Derived units** specify conversion to their base unit. There are two types:
+
+#### Simple Linear Conversions (using `factor`)
+
+For units where conversion is a simple multiplication:
+
+```dart
+{"name": "kilometer", "symbol": "km", "baseUnit": "meter", "factor": 1000}
+{"name": "inch", "symbol": "in", "baseUnit": "meter", "factor": 0.0254}
+{"name": "pound-force", "baseUnit": "newton", "factor": 4.44822}
+```
+
+The `factor` converts **from** the defined unit **to** the base unit:
+
+```dart
+// 1 kilometer = 1000 meters
+{"name": "kilometer", "baseUnit": "meter", "factor": 1000}
+
+// 1 inch = 0.0254 meters
+{"name": "inch", "baseUnit": "meter", "factor": 0.0254}
+```
+
+#### Complex Conversions (using `toBase` and `fromBase`)
+
+For units requiring non-linear conversions (e.g., temperature scales), use `toBase` and `fromBase` expressions. The variable `x` represents the value to convert.
+
+**Example: Celsius to Kelvin**
+```dart
+{
+  "name": "Celsius",
+  "symbol": "°C",
+  "baseUnit": "Kelvin",
+  "toBase": "x + 273.15",      // °C → K
+  "fromBase": "x - 273.15",    // K → °C
+}
+```
+
+**Example: Fahrenheit to Kelvin**
+```dart
+{
+  "name": "Fahrenheit",
+  "symbol": "°F",
+  "baseUnit": "Kelvin",
+  "toBase": "(x - 32) * 5/9 + 273.15",   // °F → K
+  "fromBase": "(x - 273.15) * 9/5 + 32", // K → °F
+}
+```
+
+**Example: Multi-line conversion (Gas Mark to Kelvin)**
+```dart
+{
+  "name": "Gas Mark",
+  "symbol": "GM",
+  "baseUnit": "Kelvin",
+  "toBase": r"""
+    if (x < 1) {
+      double celsius = (243 - 25 * (log(1 / x) / log(2))) / 1.8;
+      return celsius + 273.15;
+    } else {
+      double celsius = x * 14 + 121;
+      return celsius + 273.15;
+    }
+  """,
+  "fromBase": """
+    double celsius = x - 273.15;
+    if (celsius < 135) {
+      return pow(2, (1.8 * celsius - 243) / 25);
+    } else {
+      return (celsius - 121) / 14;
+    }
+  """
+}
+```
+
+### Common Temperature Conversions
+
+| Unit       | toBase (→ K)                 | fromBase (← K)               |
+|------------|------------------------------|------------------------------|
+| Celsius    | `x + 273.15`                 | `x - 273.15`                 |
+| Fahrenheit | `(x - 32) * 5/9 + 273.15`    | `(x - 273.15) * 9/5 + 32`    |
+| Rankine    | `x * 5/9`                    | `x * 9/5`                    |
+| Réaumur    | `x * 5/4 + 273.15`           | `(x - 273.15) * 4/5`         |
+| Delisle    | `373.15 - x * 2/3`           | `(373.15 - x) * 3/2`         |
+| Rømer      | `(x - 7.5) * 40/21 + 273.15` | `(x - 273.15) * 21/40 + 7.5` |
+
+---
+
+## Writing Descriptions
+
+The `description` field uses **raw Dart string literals** (`r"""..."""`) with **Markdown** and **LaTeX** math.
+
+### Format
+
+```dart
+"description": r"""
+Short description of the formula.
+
+$$F = m \cdot a$$
+
+Where:
+- $F$: Force (Newtons)
+- $m$: Mass (kilograms)
+- $a$: Acceleration (m/s²)
+
+Additional context or notes.""",
+```
+
+### LaTeX Math
+
+Use **MathJax/KaTeX** syntax for mathematical expressions:
+
+| Type                | Syntax                      | Example                  |
+|---------------------|-----------------------------|--------------------------|
+| Inline math         | `$...$`                     | `$F = ma$`               |
+| Display math        | `$$...$$`                   | `$$E = mc^2$$`           |
+| Fractions           | `\frac{a}{b}`               | `$$\frac{1}{2}mv^2$$`    |
+| Subscripts          | `x_i`                       | `$v_0$`                  |
+| Superscripts        | `x^2`                       | `$a^2 + b^2$`            |
+| Greek letters       | `\alpha`, `\beta`, `\theta` | `$$\sin(\theta)$$`       |
+| Special symbols     | `\cdot`, `\times`, `\pm`    | `$m \cdot a$`            |
+| Units in math       | `\mathrm{m/s^2}`            | `$9.81\ \mathrm{m/s^2}$` |
+| Scientific notation | `\times 10^{-11}`           | `$6.674\times 10^{-11}$` |
+
+### Including Images
+
+Add Wikipedia or other educational images using Markdown:
+
+```markdown
+![Description](https://upload.wikimedia.org/wikipedia/commons/...)
+```
+
+**Example:**
+```dart
+"description": r"""
+Newton's law of universal gravitation.
+
+$$F = G\frac{m_1m_2}{r^2}$$
+
+![Gravitation Diagram](https://upload.wikimedia.org/wikipedia/commons/thumb/3/33/NewtonsLawOfUniversalGravitation.svg/1200px-NewtonsLawOfUniversalGravitation.svg.png)""",
+```
+
+### Description Structure
+
+A well-structured description includes:
+
+1. **Opening sentence** - Brief statement of what the formula calculates
+2. **LaTeX formula** - The mathematical expression in display mode
+3. **Variable definitions** - List of all variables with units
+4. **Additional context** - Notes, assumptions, or applications
+5. **Image** (optional) - Diagram or illustration
+
+---
+
+## Best Practices
+
+### For Formulas
+
+1. **Use clear variable names** - Single letters for physics conventions (`F`, `m`, `a`), descriptive names when clarity matters
+2. **Match units precisely** - Ensure input/output units match what the formula expects
+3. **Add validation** - Use `signal()` for invalid inputs (e.g., triangle inequality)
+4. **Include tags** - Add relevant tags for discoverability
+5. **Use LaTeX for all math** - Even simple formulas should have LaTeX representation
+6. **Add images** - Include diagrams from Wikipedia when helpful
+7. **Comment your code** - Use `//` comments before each formula object
+
+### For Units
+
+1. **Use lowercase names** - `"meter"` not `"Meter"`
+2. **Include common conversions** - Add both metric and imperial units when relevant
+3. **Use standard symbols** - Follow SI conventions where applicable
+4. **Document the factor** - Ensure conversion factors are accurate
+
+### For Descriptions
+
+1. **Be concise but complete** - Explain what the formula does and what each variable means
+2. **Use consistent formatting** - Follow the established pattern in existing files
+3. **Include units in variable definitions** - Always specify units for each variable
+4. **Add context** - Explain when/why the formula is used
+5. **Note assumptions** - Mention any constraints or special conditions
+
+---
+
+## Examples
+
+### Complete Formula Example
+
+```dart
+// Newton's Second Law
+{
+  "name": "Newton's Second Law",
+  "description": r"""
+Force equals mass times acceleration.
+
+$$F = m \cdot a$$
+
+Where:
+- $m$: Mass of object ($\mathrm{kg}$)
+- $a$: Acceleration ($\mathrm{m/s^2}$)
+
+![Newton's Second Law](https://upload.wikimedia.org/wikipedia/commons/thumb/7/73/Newtonslawsofmotion.jpg/800px-Newtonslawsofmotion.jpg)""",
+  "input": [
+    {"name": "m", "unit": "kilogram"},
+    {"name": "a", "unit": "meters per square second"}
+  ],
+  "output": {"name": "F", "unit": "newton"},
+  "d4rtCode": "F = m * a;",
+  "tags": ["physics", "mechanics", "newton"]
+}
+```
+
+### Complete Unit Example
+
+```dart
+[
+  {
+    "name": "newton",
+    "symbol": "N",
+    "isBase": true
+  },
+  {
+    "name": "kilonewton",
+    "symbol": "kN",
+    "baseUnit": "newton",
+    "factor": 1000
+  },
+  {
+    "name": "pound-force",
+    "symbol": "lbf",
+    "baseUnit": "newton",
+    "factor": 4.44822
+  }
+]
+```
+
+### Multi-line Dart Code Example
+
+```dart
+// Cosine Rule
+{
+  "name": "Cosine Rule",
+  "description": r"""
+Generalization of the Pythagorean theorem for any triangle.
+
+$$c^2 = a^2 + b^2 - 2ab\cos(C)$$
+
+Where:
+- $a$, $b$, $c$: Sides of the triangle
+- $C$: Angle opposite to side $c$""",
+  "input": [
+    {"name": "a", "unit": "meter"},
+    {"name": "b", "unit": "meter"},
+    {"name": "C", "unit": "degree"}
+  ],
+  "output": {"name": "c", "unit": "meter"},
+  "d4rtCode": """
+     var angleCRad = C * (pi / 180);
+     c = sqrt(pow(a, 2) + pow(b, 2) - 2*a*b*cos(angleCRad));
+  """,
+  "tags": ["trigonometry", "triangle", "cosine"]
+}
+```
+
+---
+
+## File Organization
+
+### Formula Categories
+
+| File                             | Topic                          |
+|----------------------------------|--------------------------------|
+| `formulas.d4rt`                  | General physics formulas       |
+| `geometry.d4rt`                  | Geometric calculations         |
+| `electromagnetism.d4rt`          | Electric and magnetic formulas |
+| `energy_and_power.d4rt`          | Energy, work, and power        |
+| `thermodynamics.d4rt`            | Heat and thermodynamics        |
+| `fluids_and_pressure.d4rt`       | Fluid mechanics                |
+| `optics.d4rt`                    | Light and optics               |
+| `trigonometry.d4rt`              | Trigonometric relations        |
+| `materials_elasticity.d4rt`      | Material properties            |
+| `medical_and_bio.d4rt`           | Medical/biological formulas    |
+| `networking.d4rt`                | Network calculations           |
+| `conversions_and_constants.d4rt` | Physical constants             |
+| `misc_math.d4rt`                 | Miscellaneous mathematics      |
+
+### Unit Categories
+
+| File                     | Unit Type              |
+|--------------------------|------------------------|
+| `distance.d4rt.units`    | Length/distance        |
+| `mass.d4rt.units`        | Mass                   |
+| `time.d4rt.units`        | Time                   |
+| `force.d4rt.units`       | Force                  |
+| `energy.d4rt.units`      | Energy                 |
+| `power.d4rt.units`       | Power                  |
+| `pressure.d4rt.units`    | Pressure               |
+| `velocity.d4rt.units`    | Speed/velocity         |
+| `area.d4rt.units`        | Area                   |
+| `volume.d4rt.units`      | Volume                 |
+| `temperature.d4rt.units` | Temperature            |
+| `angle.d4rt.units`       | Angles                 |
+| `frequency.d4rt.units`   | Frequency              |
+| `electricity.d4rt.units` | Electrical units       |
+| `derived.d4rt.units`     | Derived/compound units |
+
+---
+
+## Quick Reference
+
+### Common LaTeX Symbols
+
+| Symbol | LaTeX     | Symbol | LaTeX    |
+|--------|-----------|--------|----------|
+| ×      | `\times`  | ·      | `\cdot`  |
+| ±      | `\pm`     | ÷      | `\div`   |
+| ≤      | `\leq`    | ≥      | `\geq`   |
+| √      | `\sqrt{}` | ∞      | `\infty` |
+| π      | `\pi`     | θ      | `\theta` |
+| α      | `\alpha`  | β      | `\beta`  |
+| Δ      | `\Delta`  | δ      | `\delta` |
+| Σ      | `\Sigma`  | σ      | `\sigma` |
+| Ω      | `\Omega`  | ω      | `\omega` |
+
+### Common Dart Math Functions
+
+| Function                        | Description                       |
+|---------------------------------|-----------------------------------|
+| `sin(x)`, `cos(x)`, `tan(x)`    | Trigonometric functions (radians) |
+| `asin(x)`, `acos(x)`, `atan(x)` | Inverse trig functions            |
+| `sqrt(x)`                       | Square root                       |
+| `pow(x, y)`                     | x raised to power y               |
+| `log(x)`                        | Natural logarithm                 |
+| `log10(x)`                      | Base-10 logarithm                 |
+| `abs(x)`                        | Absolute value                    |
+| `exp(x)`                        | e raised to power x               |
+| `pi`                            | π constant                        |
+
+---
+
+## Contributing
+
+1. **Choose the right file** - Add formulas to the appropriate category file
+2. **Follow the format** - Match the structure of existing entries
+3. **Test your code** - Ensure `d4rtCode` is valid Dart syntax
+4. **Add description** - Include complete LaTeX documentation
+5. **Tag appropriately** - Add relevant tags for searchability
+6. **Review** - Check existing formulas for consistency
+
+For questions or clarifications, refer to existing formulas in the `assets/formulas/` directory as examples.
diff --git a/assets/formulas/networking.d4rt b/assets/formulas/networking.d4rt
new file mode 100644
index 0000000..ceda27e
--- /dev/null
+++ b/assets/formulas/networking.d4rt
@@ -0,0 +1,83 @@
+[
+  // IP Subnet and Broadcast Calculator
+  {
+    "name": "IP Subnet and Broadcast",
+    "description": r"""
+Calculates the network (subnet) address and broadcast address for an IPv4 address with CIDR notation.
+
+**Input format:** `ip_address/prefix` where:
+- `ip_address`: IPv4 address in dotted decimal notation (e.g., `192.168.1.100`)
+- `prefix`: CIDR prefix length (1-30) or subnet mask in dotted notation (e.g., `24` or `255.255.255.0`)
+
+**Output:**
+- `subnet`: Network address in dotted decimal notation
+- `broadcast`: Broadcast address in dotted decimal notation
+
+**Examples:**
+- Input: `192.168.1.100/24` → Subnet: `192.168.1.0`, Broadcast: `192.168.1.255`
+- Input: `10.0.0.50/8` → Subnet: `10.0.0.0`, Broadcast: `10.255.255.255`
+- Input: `172.16.5.100/16` → Subnet: `172.16.0.0`, Broadcast: `172.16.255.255`""",
+    "input": [
+      {"name": "ipWithMask", "unit": "scalar"}
+    ],
+    "output": {"name": "subnet", "unit": "scalar"},
+    "d4rtCode": """
+       var input = ipWithMask.toString();
+       var slashIndex = input.indexOf('/');
+       if (slashIndex == -1) {
+         subnet = 'error: no / found';
+         broadcast = '';
+       } else {
+         var ipPart = input.substring(0, slashIndex).trim();
+         var maskPart = input.substring(slashIndex + 1).trim();
+         
+         // Parse IP address
+         var ipParts = ipPart.split('.');
+         if (ipParts.length != 4) {
+           subnet = 'error: invalid IP';
+           broadcast = '';
+         } else {
+           var octet1 = int.parse(ipParts[0]);
+           var octet2 = int.parse(ipParts[1]);
+           var octet3 = int.parse(ipParts[2]);
+           var octet4 = int.parse(ipParts[3]);
+           
+           // Convert IP to 32-bit integer
+           var ipInt = (octet1 << 24) | (octet2 << 16) | (octet3 << 8) | octet4;
+           
+           // Parse mask (CIDR prefix or dotted notation)
+           int maskInt;
+           if (maskPart.contains('.')) {
+             var maskParts = maskPart.split('.');
+             var m1 = int.parse(maskParts[0]);
+             var m2 = int.parse(maskParts[1]);
+             var m3 = int.parse(maskParts[2]);
+             var m4 = int.parse(maskParts[3]);
+             maskInt = (m1 << 24) | (m2 << 16) | (m3 << 8) | m4;
+           } else {
+             var prefix = int.parse(maskPart);
+             maskInt = prefix == 0 ? 0 : (-1 << (32 - prefix));
+           }
+           
+           // Calculate subnet and broadcast
+           var subnetInt = ipInt & maskInt;
+           var broadcastInt = subnetInt | (~maskInt & 0xFFFFFFFF);
+           
+           // Convert back to dotted notation
+           var s1 = (subnetInt >> 24) & 0xFF;
+           var s2 = (subnetInt >> 16) & 0xFF;
+           var s3 = (subnetInt >> 8) & 0xFF;
+           var s4 = subnetInt & 0xFF;
+           subnet = '\$s1.\$s2.\$s3.\$s4';
+           
+           var b1 = (broadcastInt >> 24) & 0xFF;
+           var b2 = (broadcastInt >> 16) & 0xFF;
+           var b3 = (broadcastInt >> 8) & 0xFF;
+           var b4 = broadcastInt & 0xFF;
+           broadcast = '\$b1.\$b2.\$b3.\$b4';
+         }
+       }
+    """,
+    "tags": ["networking", "ip", "subnet", "broadcast", "cidr"]
+  }
+]
diff --git a/lib/ai/formula_editor.dart b/lib/ai/formula_editor.dart
new file mode 100644
index 0000000..ff7805e
--- /dev/null
+++ b/lib/ai/formula_editor.dart
@@ -0,0 +1,705 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_markdown_plus_latex/flutter_markdown_plus_latex.dart';
+import 'package:flutter_markdown_plus/flutter_markdown_plus.dart';
+import 'package:markdown/markdown.dart' as markdown;
+import '../formula_models.dart';
+import '../corpus.dart';
+import 'formula_screen.dart';
+import 'unit_dropdown.dart';
+
+/// A screen for editing a Formula's properties including name, description,
+/// input/output variables, and d4rt code.
+class FormulaEditor extends StatefulWidget {
+  final Formula formula;
+  final Corpus corpus;
+
+  const FormulaEditor({
+    super.key,
+    required this.formula,
+    required this.corpus,
+  });
+
+  @override
+  State<FormulaEditor> createState() => _FormulaEditorState();
+}
+
+class _FormulaEditorState extends State<FormulaEditor> {
+  final _formKey = GlobalKey<FormState>();
+  late TextEditingController _nameController;
+  late TextEditingController _descriptionController;
+  late TextEditingController _d4rtCodeController;
+  
+  // Track input variables
+  final List<_InputVariableRowData> _inputVariables = [];
+  
+  // Output variable
+  late _OutputVariableRowData _outputVariable;
+  
+  bool _isPreviewVisible = false;
+
+  @override
+  void initState() {
+    super.initState();
+    _nameController = TextEditingController(text: widget.formula.name);
+    _descriptionController = TextEditingController(text: widget.formula.description ?? '');
+    _d4rtCodeController = TextEditingController(text: widget.formula.d4rtCode);
+    
+    // Initialize input variables
+    for (final input in widget.formula.input) {
+      _inputVariables.add(_InputVariableRowData(
+        nameController: TextEditingController(text: input.name),
+        unit: input.unit,
+        values: input.values != null ? List.from(input.values!) : null,
+      ));
+    }
+    
+    // Initialize output variable
+    _outputVariable = _OutputVariableRowData(
+      nameController: TextEditingController(text: widget.formula.output.name),
+      unit: widget.formula.output.unit,
+    );
+  }
+
+  @override
+  void dispose() {
+    _nameController.dispose();
+    _descriptionController.dispose();
+    _d4rtCodeController.dispose();
+    for (final variable in _inputVariables) {
+      variable.nameController.dispose();
+    }
+    _outputVariable.nameController.dispose();
+    super.dispose();
+  }
+
+  void _addInputVariable() {
+    setState(() {
+      _inputVariables.add(_InputVariableRowData(
+        nameController: TextEditingController(text: 'var${_inputVariables.length + 1}'),
+        unit: null,
+        values: null,
+      ));
+    });
+  }
+
+  void _removeInputVariable(int index) {
+    setState(() {
+      _inputVariables.removeAt(index);
+    });
+  }
+
+  void _showPreview() {
+    setState(() {
+      _isPreviewVisible = true;
+    });
+  }
+
+  void _hidePreview() {
+    setState(() {
+      _isPreviewVisible = false;
+    });
+  }
+
+  void _testFormula() {
+    // Validate the formula before testing
+    if (!_validateFormula()) {
+      return;
+    }
+
+    final formula = _buildFormula();
+    if (formula == null) return;
+
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (context) => FormulaScreen(
+          formula: formula,
+          corpus: widget.corpus,
+        ),
+      ),
+    );
+  }
+
+  bool _validateFormula() {
+    // Validate name
+    if (_nameController.text.trim().isEmpty) {
+      _showErrorDialog('Formula name cannot be empty');
+      return false;
+    }
+
+    // Validate output name
+    if (_outputVariable.nameController.text.trim().isEmpty) {
+      _showErrorDialog('Output variable name cannot be empty');
+      return false;
+    }
+
+    // Validate input variable names
+    for (final variable in _inputVariables) {
+      if (variable.nameController.text.trim().isEmpty) {
+        _showErrorDialog('Input variable names cannot be empty');
+        return false;
+      }
+    }
+
+    // Validate d4rt code
+    if (_d4rtCodeController.text.trim().isEmpty) {
+      _showErrorDialog('D4RT code cannot be empty');
+      return false;
+    }
+
+    return true;
+  }
+
+  Formula? _buildFormula() {
+    try {
+      final input = <VariableSpec>[];
+      for (final variable in _inputVariables) {
+        input.add(VariableSpec(
+          name: variable.nameController.text.trim(),
+          unit: variable.unit,
+          values: variable.values,
+        ));
+      }
+
+      final output = VariableSpec(
+        name: _outputVariable.nameController.text.trim(),
+        unit: _outputVariable.unit,
+      );
+
+      return Formula(
+        name: _nameController.text.trim(),
+        description: _descriptionController.text.isEmpty ? null : _descriptionController.text,
+        input: input,
+        output: output,
+        d4rtCode: _d4rtCodeController.text,
+        tags: widget.formula.tags, // Preserve existing tags
+      );
+    } catch (e) {
+      _showErrorDialog('Error building formula: $e');
+      return null;
+    }
+  }
+
+  void _saveFormula() {
+    if (!_validateFormula()) {
+      return;
+    }
+
+    final formula = _buildFormula();
+    if (formula == null) return;
+
+    // For now, just show a success message
+    // In a real implementation, this would save to database
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Text('Formula "${formula.name}" saved successfully!'),
+        backgroundColor: Theme.of(context).colorScheme.primary,
+      ),
+    );
+  }
+
+  void _showErrorDialog(String message) {
+    showDialog(
+      context: context,
+      builder: (BuildContext context) {
+        return AlertDialog(
+          title: const Text('Error'),
+          content: Text(message),
+          actions: <Widget>[
+            TextButton(
+              onPressed: () {
+                Navigator.of(context).pop();
+              },
+              child: const Text('OK'),
+            ),
+          ],
+        );
+      },
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: const Text('Edit Formula'),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.play_arrow),
+            onPressed: _testFormula,
+            tooltip: 'Test Formula',
+          ),
+          IconButton(
+            icon: const Icon(Icons.save),
+            onPressed: _saveFormula,
+            tooltip: 'Save',
+          ),
+        ],
+      ),
+      body: Form(
+        key: _formKey,
+        child: Padding(
+          padding: const EdgeInsets.all(16.0),
+          child: ListView(
+            children: [
+              _buildNameSection(),
+              const SizedBox(height: 16),
+              _buildDescriptionSection(),
+              const SizedBox(height: 16),
+              _buildInputVariablesSection(),
+              const SizedBox(height: 16),
+              _buildOutputVariableSection(),
+              const SizedBox(height: 16),
+              _buildD4rtCodeSection(),
+              const SizedBox(height: 32),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildNameSection() {
+    return TextFormField(
+      controller: _nameController,
+      decoration: const InputDecoration(
+        labelText: 'Formula Name',
+        border: OutlineInputBorder(),
+        prefixIcon: Icon(Icons.title),
+      ),
+      validator: (value) {
+        if (value == null || value.trim().isEmpty) {
+          return 'Name is required';
+        }
+        return null;
+      },
+    );
+  }
+
+  Widget _buildDescriptionSection() {
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceBetween,
+              children: [
+                const Text(
+                  'Description (Markdown)',
+                  style: TextStyle(
+                    fontSize: 16,
+                    fontWeight: FontWeight.bold,
+                  ),
+                ),
+                Row(
+                  mainAxisSize: MainAxisSize.min,
+                  children: [
+                    if (_isPreviewVisible)
+                      TextButton.icon(
+                        icon: const Icon(Icons.visibility_off),
+                        label: const Text('Hide Preview'),
+                        onPressed: _hidePreview,
+                      )
+                    else
+                      TextButton.icon(
+                        icon: const Icon(Icons.visibility),
+                        label: const Text('Preview'),
+                        onPressed: _showPreview,
+                      ),
+                  ],
+                ),
+              ],
+            ),
+            const SizedBox(height: 8),
+            if (_isPreviewVisible) ...[
+              Container(
+                padding: const EdgeInsets.all(8),
+                decoration: BoxDecoration(
+                  color: Theme.of(context).colorScheme.surfaceVariant,
+                  borderRadius: BorderRadius.circular(8),
+                ),
+                child: Markdown(
+                  data: _descriptionController.text,
+                  shrinkWrap: true,
+                  builders: {
+                    'latex': LatexElementBuilder(),
+                  },
+                  extensionSet: markdown.ExtensionSet(
+                    [LatexBlockSyntax()],
+                    [LatexInlineSyntax()],
+                  ),
+                ),
+              ),
+              const SizedBox(height: 16),
+            ],
+            TextFormField(
+              controller: _descriptionController,
+              decoration: const InputDecoration(
+                hintText: 'Enter formula description (supports Markdown and LaTeX)',
+                border: OutlineInputBorder(),
+              ),
+              maxLines: 5,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildInputVariablesSection() {
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            const Text(
+              'Input Variables',
+              style: TextStyle(
+                fontSize: 16,
+                fontWeight: FontWeight.bold,
+              ),
+            ),
+            const SizedBox(height: 8),
+            ..._inputVariables.asMap().entries.map((entry) {
+              final index = entry.key;
+              final variable = entry.value;
+              return _buildInputVariableRow(index, variable);
+            }).toList(),
+            const SizedBox(height: 8),
+            ElevatedButton.icon(
+              icon: const Icon(Icons.add),
+              label: const Text('Add Input Variable'),
+              onPressed: _addInputVariable,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildInputVariableRow(int index, _InputVariableRowData variable) {
+    return Card(
+      margin: const EdgeInsets.only(bottom: 8),
+      child: Padding(
+        padding: const EdgeInsets.all(8.0),
+        child: Column(
+          children: [
+            Row(
+              children: [
+                Expanded(
+                  flex: 2,
+                  child: TextFormField(
+                    controller: variable.nameController,
+                    decoration: const InputDecoration(
+                      labelText: 'Name',
+                      border: OutlineInputBorder(),
+                    ),
+                  ),
+                ),
+                const SizedBox(width: 8),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      const Text('Base Unit', style: TextStyle(fontSize: 12)),
+                      DropdownButtonFormField<String?>(
+                        value: _getBaseUnit(variable.unit),
+                        decoration: const InputDecoration(
+                          border: OutlineInputBorder(),
+                          contentPadding: EdgeInsets.symmetric(horizontal: 12, vertical: 0),
+                        ),
+                        items: [
+                          const DropdownMenuItem<String?>(
+                            value: null,
+                            child: Text('None', style: TextStyle(fontSize: 14)),
+                          ),
+                          ..._getAllBaseUnits().map((baseUnit) {
+                            return DropdownMenuItem<String?>(
+                              value: baseUnit,
+                              child: Text(baseUnit, style: const TextStyle(fontSize: 14)),
+                            );
+                          }).toList(),
+                        ],
+                        onChanged: (baseUnit) {
+                          setState(() {
+                            variable.unit = baseUnit;
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+                const SizedBox(width: 8),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      const Text('Derived Unit', style: TextStyle(fontSize: 12)),
+                      DropdownButtonFormField<String?>(
+                        value: variable.unit,
+                        decoration: const InputDecoration(
+                          border: OutlineInputBorder(),
+                          contentPadding: EdgeInsets.symmetric(horizontal: 12, vertical: 0),
+                        ),
+                        items: [
+                          const DropdownMenuItem<String?>(
+                            value: null,
+                            child: Text('None', style: TextStyle(fontSize: 14)),
+                          ),
+                          ..._getDerivedUnits(variable.unit).map((unit) {
+                            final unitSpec = widget.corpus.getUnit(unit);
+                            return DropdownMenuItem<String?>(
+                              value: unit,
+                              child: Text('${unitSpec.symbol} - ${unit}', 
+                                style: const TextStyle(fontSize: 14),
+                                overflow: TextOverflow.ellipsis,
+                              ),
+                            );
+                          }).toList(),
+                        ],
+                        onChanged: (unit) {
+                          setState(() {
+                            variable.unit = unit;
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+                const SizedBox(width: 8),
+                IconButton(
+                  icon: const Icon(Icons.delete, color: Colors.red),
+                  onPressed: () => _removeInputVariable(index),
+                  tooltip: 'Delete variable',
+                ),
+              ],
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildOutputVariableSection() {
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            const Text(
+              'Output Variable',
+              style: TextStyle(
+                fontSize: 16,
+                fontWeight: FontWeight.bold,
+              ),
+            ),
+            const SizedBox(height: 8),
+            Row(
+              children: [
+                Expanded(
+                  flex: 2,
+                  child: TextFormField(
+                    controller: _outputVariable.nameController,
+                    decoration: const InputDecoration(
+                      labelText: 'Name',
+                      border: OutlineInputBorder(),
+                    ),
+                  ),
+                ),
+                const SizedBox(width: 8),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      const Text('Base Unit', style: TextStyle(fontSize: 12)),
+                      DropdownButtonFormField<String?>(
+                        value: _getBaseUnit(_outputVariable.unit),
+                        decoration: const InputDecoration(
+                          border: OutlineInputBorder(),
+                          contentPadding: EdgeInsets.symmetric(horizontal: 12, vertical: 0),
+                        ),
+                        items: [
+                          const DropdownMenuItem<String?>(
+                            value: null,
+                            child: Text('None', style: TextStyle(fontSize: 14)),
+                          ),
+                          ..._getAllBaseUnits().map((baseUnit) {
+                            return DropdownMenuItem<String?>(
+                              value: baseUnit,
+                              child: Text(baseUnit, style: const TextStyle(fontSize: 14)),
+                            );
+                          }).toList(),
+                        ],
+                        onChanged: (baseUnit) {
+                          setState(() {
+                            _outputVariable.unit = baseUnit;
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+                const SizedBox(width: 8),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      const Text('Derived Unit', style: TextStyle(fontSize: 12)),
+                      DropdownButtonFormField<String?>(
+                        value: _outputVariable.unit,
+                        decoration: const InputDecoration(
+                          border: OutlineInputBorder(),
+                          contentPadding: EdgeInsets.symmetric(horizontal: 12, vertical: 0),
+                        ),
+                        items: [
+                          const DropdownMenuItem<String?>(
+                            value: null,
+                            child: Text('None', style: TextStyle(fontSize: 14)),
+                          ),
+                          ..._getDerivedUnits(_outputVariable.unit).map((unit) {
+                            final unitSpec = widget.corpus.getUnit(unit);
+                            return DropdownMenuItem<String?>(
+                              value: unit,
+                              child: Text('${unitSpec.symbol} - ${unit}', 
+                                style: const TextStyle(fontSize: 14),
+                                overflow: TextOverflow.ellipsis,
+                              ),
+                            );
+                          }).toList(),
+                        ],
+                        onChanged: (unit) {
+                          setState(() {
+                            _outputVariable.unit = unit;
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+              ],
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildD4rtCodeSection() {
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            const Text(
+              'D4RT Code',
+              style: TextStyle(
+                fontSize: 16,
+                fontWeight: FontWeight.bold,
+              ),
+            ),
+            const SizedBox(height: 8),
+            Container(
+              decoration: BoxDecoration(
+                border: Border.all(color: Theme.of(context).dividerColor),
+                borderRadius: BorderRadius.circular(4),
+              ),
+              child: Column(
+                children: [
+                  Container(
+                    padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
+                    decoration: BoxDecoration(
+                      color: Theme.of(context).colorScheme.surfaceVariant,
+                      borderRadius: const BorderRadius.only(
+                        topLeft: Radius.circular(4),
+                        topRight: Radius.circular(4),
+                      ),
+                    ),
+                    child: Row(
+                      children: [
+                        Icon(Icons.code, size: 16, color: Theme.of(context).colorScheme.primary),
+                        const SizedBox(width: 8),
+                        Text(
+                          'Dart Syntax',
+                          style: TextStyle(
+                            fontSize: 12,
+                            fontWeight: FontWeight.bold,
+                            color: Theme.of(context).colorScheme.primary,
+                          ),
+                        ),
+                      ],
+                    ),
+                  ),
+                  TextFormField(
+                    controller: _d4rtCodeController,
+                    decoration: const InputDecoration(
+                      hintText: 'Enter D4RT/Dart code here',
+                      border: InputBorder.none,
+                      contentPadding: EdgeInsets.all(12),
+                    ),
+                    maxLines: 10,
+                    style: const TextStyle(
+                      fontFamily: 'monospace',
+                      fontSize: 14,
+                    ),
+                  ),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  // Helper methods for unit management
+  String? _getBaseUnit(String? unit) {
+    if (unit == null) return null;
+    try {
+      return widget.corpus.getUnit(unit).baseUnit;
+    } catch (e) {
+      return null;
+    }
+  }
+
+  List<String> _getAllBaseUnits() {
+    final baseUnits = <String>{};
+    for (final unit in widget.corpus.allUnits()) {
+      baseUnits.add(unit.baseUnit);
+    }
+    return baseUnits.toList()..sort();
+  }
+
+  List<String> _getDerivedUnits(String? baseUnit) {
+    if (baseUnit == null) return [];
+    return widget.corpus.unitsOfSameMagnitude(baseUnit)..sort();
+  }
+}
+
+// Data classes to track variable state
+class _InputVariableRowData {
+  final TextEditingController nameController;
+  String? unit;
+  List<dynamic>? values;
+
+  _InputVariableRowData({
+    required this.nameController,
+    this.unit,
+    this.values,
+  });
+}
+
+class _OutputVariableRowData {
+  final TextEditingController nameController;
+  String? unit;
+
+  _OutputVariableRowData({
+    required this.nameController,
+    this.unit,
+  });
+}
diff --git a/lib/ai/formula_list.dart b/lib/ai/formula_list.dart
index 5348710..a6b2129 100644
--- a/lib/ai/formula_list.dart
+++ b/lib/ai/formula_list.dart
@@ -3,6 +3,7 @@ import 'package:flutter/services.dart'; // For Clipboard
 import 'package:d4rt_formulas/formula_models.dart';
 import '../corpus.dart';
 import 'formula_screen.dart';
+import 'formula_editor.dart';
 import 'package:share_plus/share_plus.dart';
 
 class FormulaList extends StatefulWidget {
@@ -55,13 +56,13 @@ class _FormulaListState extends State<FormulaList> {
     try {
       // Get the formula and its dependencies
       final dependencies = widget.corpus.withDependencies(formula);
-      
+
       // Convert each dependency to its string literal representation
       final literals = dependencies.map((element) => element.toStringLiteral()).toList();
-      
+
       // Create an array string literal containing all the elements
       final exportString = '[${literals.join(', ')}]';
-      
+
       // Share the string
       await Share.share(
         exportString,
@@ -72,6 +73,18 @@ class _FormulaListState extends State<FormulaList> {
     }
   }
 
+  void _editFormula(Formula formula) {
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (context) => FormulaEditor(
+          formula: formula,
+          corpus: widget.corpus,
+        ),
+      ),
+    );
+  }
+
   void _copyFormula(Formula formula) async {
     try {
       // Get the formula and its dependencies
@@ -144,35 +157,45 @@ class _FormulaListState extends State<FormulaList> {
                 subtitle: formula.tags.isNotEmpty
                     ? Text('Tags: ${formula.tags.join(', ')}')
                     : null,
-                trailing: PopupMenuButton(
-                  icon: Icon(Icons.share),
-                  onSelected: (value) {
-                    if (value == 'share') {
-                      _shareFormula(formula);
-                    } else if (value == 'copy') {
-                      _copyFormula(formula);
-                    }
-                  },
-                  itemBuilder: (context) => [
-                    PopupMenuItem(
-                      value: 'share',
-                      child: Row(
-                        children: [
-                          Icon(Icons.share),
-                          SizedBox(width: 8),
-                          Text('Share'),
-                        ],
-                      ),
+                trailing: Row(
+                  mainAxisSize: MainAxisSize.min,
+                  children: [
+                    IconButton(
+                      icon: const Icon(Icons.edit),
+                      onPressed: () => _editFormula(formula),
+                      tooltip: 'Edit Formula',
                     ),
-                    PopupMenuItem(
-                      value: 'copy',
-                      child: Row(
-                        children: [
-                          Icon(Icons.copy),
-                          SizedBox(width: 8),
-                          Text('Copy to clipboard'),
-                        ],
-                      ),
+                    PopupMenuButton(
+                      icon: const Icon(Icons.share),
+                      onSelected: (value) {
+                        if (value == 'share') {
+                          _shareFormula(formula);
+                        } else if (value == 'copy') {
+                          _copyFormula(formula);
+                        }
+                      },
+                      itemBuilder: (context) => [
+                        PopupMenuItem(
+                          value: 'share',
+                          child: Row(
+                            children: [
+                              Icon(Icons.share),
+                              SizedBox(width: 8),
+                              Text('Share'),
+                            ],
+                          ),
+                        ),
+                        PopupMenuItem(
+                          value: 'copy',
+                          child: Row(
+                            children: [
+                              Icon(Icons.copy),
+                              SizedBox(width: 8),
+                              Text('Copy to clipboard'),
+                            ],
+                          ),
+                        ),
+                      ],
                     ),
                   ],
                 ),
diff --git a/lib/ai/formula_screen.dart b/lib/ai/formula_screen.dart
index 7bf6dc5..5395598 100644
--- a/lib/ai/formula_screen.dart
+++ b/lib/ai/formula_screen.dart
@@ -8,6 +8,7 @@ import '../formula_evaluator.dart';
 import '../corpus.dart';
 import '../error_handler.dart';
 import 'unit_dropdown.dart';
+import 'formula_editor.dart';
 
 class FormulaScreen extends StatefulWidget {
   final Formula formula;
@@ -171,7 +172,26 @@ class _FormulaScreenState extends State<FormulaScreen> {
   @override
   Widget build(BuildContext context) {
     return Scaffold(
-      appBar: AppBar(title: Text(widget.formula.name)),
+      appBar: AppBar(
+        title: Text(widget.formula.name),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.edit),
+            onPressed: () {
+              Navigator.push(
+                context,
+                MaterialPageRoute(
+                  builder: (context) => FormulaEditor(
+                    formula: widget.formula,
+                    corpus: widget.corpus,
+                  ),
+                ),
+              );
+            },
+            tooltip: 'Edit Formula',
+          ),
+        ],
+      ),
       body: Form(
         key: _formKey,
         child: Padding(
diff --git a/lib/defaults/default_corpus.dart b/lib/defaults/default_corpus.dart
index 1719f04..f712f97 100644
--- a/lib/defaults/default_corpus.dart
+++ b/lib/defaults/default_corpus.dart
@@ -62,6 +62,7 @@ Future<Corpus> createDefaultCorpus() async{
       "assets/formulas/medical_and_bio.d4rt",
       "assets/formulas/conversions_and_constants.d4rt",
       "assets/formulas/misc_math.d4rt",
+      "assets/formulas/networking.d4rt",
     ];
 
     for (final formRes in formulaResources) {