Growth & Strategy

Programming Languages Lindy AI Actually Supports (After Building 50+ Automations)


Personas

SaaS & Startup

Time to ROI

Short-term (< 3 months)

Here's the thing nobody tells you about no-code platforms: they always hit a wall. You start building beautiful workflows, everything's going great, then BAM – you need to do something specific that the visual builder just can't handle.

I've been building AI automations for clients for months now, and this exact scenario happens over and over. Marketing teams get excited about automating their lead qualification, everything works until they need custom data processing. Sales teams want to automate outreach, but their CRM integration needs specific formatting. Operations teams build gorgeous workflows, then realize they need to parse JSON or manipulate arrays.

Most no-code tools leave you stuck at this point. You either accept the limitations or hire a developer to build custom integrations. But that's exactly why I'm excited about what Lindy AI has done with their SDK and code execution capabilities.

Here's what you'll learn in this playbook:

  • The exact programming languages Lindy's SDK actually supports (spoiler: it's not what most people think)

  • Why JavaScript and Python became the only two languages that matter for 99% of automation needs

  • My real experience building custom code actions for multiple clients and what actually works

  • The hidden capabilities of E2B integration that most users don't know about

  • When to use custom code vs when to stick with no-code (this decision saves weeks of work)

If you're hitting the limits of no-code automation or wondering whether Lindy can handle your specific technical requirements, this guide will give you the real story from someone who's actually built with it.

Industry Reality

What the automation community assumes

Walk into any no-code community and you'll hear the same assumptions about AI automation platforms. Everyone assumes that if a platform calls itself "no-code," it must be limited to visual workflows only. The conversations always go the same way:

"Can it handle custom data processing?" – Usually no
"What about complex API integrations?" – You're stuck with what they provide
"Custom business logic?" – Hope your use case fits their templates
"Real programming when needed?" – Time to hire a developer

This creates a false choice that the industry has accepted: beautiful no-code interfaces for simple tasks, or full development environments for anything complex. Most platforms pick a side and stay there.

The typical advice from automation experts is to map out your requirements first, then choose your tool based on complexity. Simple workflows? Use Zapier. Complex logic? Build custom with Python. Need both? Good luck managing multiple systems.

Here's where the conventional wisdom gets it wrong: this either/or thinking assumes that business needs stay in neat categories. In reality, every automation starts simple and grows complex. You begin with "send an email when a form is submitted" and six months later you need "analyze the sentiment of the submission, route it based on custom business rules, and trigger different workflows based on the customer's purchase history."

The industry's solution has been integration hell – connecting multiple tools, maintaining API bridges, and constantly fighting with data sync issues. It's why most automation projects either stay embarrassingly simple or become expensive custom development nightmares.

What the experts miss is that the future isn't about choosing between no-code and custom code. It's about platforms that can seamlessly blend both when you need them.

Who am I

Consider me as your business complice.

7 years of freelance experience working with SaaS and Ecommerce brands.

OK, so here's where I need to be honest with you. When I first heard about Lindy AI, I was skeptical as hell. Another "revolutionary" no-code platform promising to change everything? Yeah, right.

I'd been burned by this story before. Clients would come to me excited about some new automation tool they'd discovered. We'd build something basic, it would work great, then reality would hit. They'd need one specific feature – custom data parsing, complex conditional logic, or integration with their weird internal API – and we'd hit the wall.

The breaking point came with a SaaS client who needed lead qualification automation. Their requirements seemed simple: take incoming leads, score them based on company size and industry, then route them to the right sales rep. Standard stuff, right?

Wrong. Their scoring algorithm was complex – it needed to cross-reference multiple data sources, apply weighted scoring based on dozens of variables, and handle edge cases that their sales team had developed over years. No visual workflow builder could handle this logic.

We tried everything. Zapier with multiple steps and lookup tables. Make.com with complex routing. Airtable with formulas. Each solution was either too limited or so convoluted that maintaining it became a full-time job.

That's when I discovered Lindy's code actions feature. At first, I dismissed it as another gimmick – most platforms claim to support "custom code" but it's usually just basic formula fields or limited scripting.

But this was different. Through their partnership with E2B, Lindy actually provides secure, sandboxed environments where you can run real Python and JavaScript code. Not pseudo-code, not simplified scripting – actual programming languages with full capabilities.

The client challenge became my testing ground. Could Lindy really bridge the gap between no-code simplicity and custom code power? I was about to find out.

My experiments

Here's my playbook

What I ended up doing and the results.

Here's exactly what I did to solve the lead scoring challenge, and how you can apply the same approach to your own automation needs.

Step 1: Start with No-Code Foundation
I built the basic workflow using Lindy's visual interface. Trigger: new lead comes in via webhook. Actions: enrich the lead data, prepare it for scoring. This part took about 15 minutes and worked perfectly.

The beauty of this approach is that 80% of your automation can still be no-code. You're not throwing away the simplicity – you're enhancing it where needed.

Step 2: Insert Custom Code Where It Matters
For the scoring logic, I added a Code Action step. Lindy gives you a clean interface where you can choose between Python or JavaScript, then write your custom logic. Here's what's brilliant about their implementation:

You can reference data from previous steps in your workflow directly in your code. The lead data I enriched in step 1 became variables I could use in my Python script. No complex API calls or data passing – it just works.

Step 3: Build Real Logic, Not Workarounds
Instead of trying to recreate complex business logic with dozens of conditional steps, I wrote a 50-line Python function that handled all the scoring rules. It pulled data from their CRM API, applied weighted algorithms, and returned a scored lead object.

This is where the power becomes obvious. I could use actual programming constructs – loops, functions, error handling, external libraries. The code ran in a secure environment that Lindy provisions automatically.

Step 4: Continue with No-Code
Once my code action returned the scored lead, the workflow continued with visual steps. Route to the right sales rep based on score and territory. Send Slack notifications. Update the CRM. All the standard no-code stuff worked seamlessly with my custom code output.

The result? A workflow that looks simple from the outside but handles complex business logic internally. The client got exactly what they needed without compromising on either simplicity or power.

What surprised me most was how natural this felt. You're not context-switching between different tools or environments. The custom code lives inside the same workflow as everything else. You edit it, test it, and deploy it all in the same interface.

Language Support

Python and JavaScript are the only two languages supported, but that covers 99% of automation needs. Both run in secure E2B sandboxes with full library access.

Integration Power

Custom code can access data from previous workflow steps directly as variables. No complex API calls or data transformation needed between steps.

Development Experience

Built-in code editor with syntax highlighting. Real-time testing within the workflow. Version control and rollback capabilities for code changes.

Security Model

All code runs in isolated sandboxes. No access to Lindy's infrastructure. Automatic scaling and resource management handled by E2B integration.

The results speak for themselves. What would have taken weeks to build with traditional integration tools, I completed in an afternoon. The lead scoring automation has been running flawlessly for months.

But the bigger win was psychological. For the first time, I had a platform where I could say "yes" to complex requirements without immediately thinking about technical limitations. When clients ask for custom logic now, it's not a roadblock – it's just another step in the workflow.

The performance has been solid too. Code actions execute quickly, typically under 2 seconds even for complex operations. The E2B integration handles scaling automatically – I've never seen performance issues even when processing large datasets.

Most importantly, maintenance is simple. When the client needed to adjust their scoring algorithm, I just updated the Python code. No complex deployments, no separate hosting concerns, no API versioning headaches. The change was live immediately.

Learnings

What I've learned and the mistakes I've made.

Sharing so you don't make them.

Pick Your Languages Strategically
Python for data processing, API integrations, and complex business logic. JavaScript for web scraping, DOM manipulation, and frontend-style data handling. These two cover every automation scenario I've encountered.

Start No-Code, Add Code When Needed
Don't overthink it. Build your workflow visually first, then identify where custom logic would solve problems more elegantly than visual workarounds. The best automations blend both approaches seamlessly.

Leverage the E2B Security Model
Your code runs in completely isolated environments. This means you can use external libraries, make API calls, and process sensitive data without security concerns. It's not just a scripting sandbox – it's a full execution environment.

Test Incrementally
Use Lindy's testing features to validate your code with real data before deploying. The ability to test custom code within the workflow context is invaluable for catching edge cases.

Think Beyond Simple Scripts
Don't limit yourself to basic data transformation. I've built complex data analysis routines, integrated with specialized APIs, and even implemented machine learning models. The platform can handle much more than most people realize.

Document Your Custom Functions
When you build custom code actions, add clear comments and documentation. Future you (and your team) will thank you when requirements change.

Monitor Resource Usage
While E2B handles scaling automatically, be mindful of execution time and memory usage in your code. Optimize for efficiency, especially for high-volume workflows.

How you can adapt this to your Business

My playbook, condensed for your use case.

For your SaaS / Startup

For SaaS companies, focus on Python for API integrations with your existing tech stack. Build custom logic for user onboarding flows, data synchronization between tools, and complex business rule automation.

For your Ecommerce store

For e-commerce, JavaScript excels at web scraping for competitive pricing, inventory management scripts, and custom order processing logic. Python handles payment processing integrations and advanced analytics.

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