Building Resilient Workflows to Handle Partial Failures
Z
Zack Saadioui
8/12/2025
Don't Let a Small Glitch Wreck Your Whole System: Building Workflows That Bounce Back from Partial Failures
Here's the thing about building complex, multi-step processes, especially in the world of microservices & distributed systems: stuff breaks. It’s not a matter of if, but when. A single network hiccup, a temporarily unresponsive service, or a database timeout can bring an entire critical operation grinding to a halt. We've all been there, staring at a failed process wondering why one tiny error caused a catastrophic domino effect. It’s SUPER frustrating.
Honestly, for a long time, the common approach was just… hope for the best. Or maybe wrap the whole thing in a giant, unwieldy transaction that would either fully succeed or fully fail. But that’s a pretty rigid & often inefficient way to handle things, especially for long-running business processes. If a customer places an order, which involves checking inventory, processing a payment, & scheduling shipping, you don't want the whole thing to explode just because the shipping label service timed out for a second. You'd be left with an inconsistent mess & a very unhappy customer.
Turns out, there's a much smarter way to think about this. Instead of building fragile, all-or-nothing systems, the pros build resilient workflows that expect & gracefully handle partial failures. It’s about designing for reality, not for a perfect-world scenario. This is where we get into some pretty cool concepts like workflow orchestration, sagas, idempotency, & circuit breakers. These aren't just fancy buzzwords; they're the building blocks of modern, resilient systems.
The Core Problem: The Domino Effect of Failure
In any distributed system, where you have multiple services talking to each other to get a job done, a failure in one service can cascade & take down others. Think about it: Service A calls Service B, which calls Service C. If C fails, B might get stuck waiting, holding up resources. Then A is stuck waiting for B. This is called a cascading failure, & it's a nightmare for system stability.
Traditional transaction models (what tech folks call ACID transactions) are great for single databases, but they don't stretch well across multiple, independent services. Trying to implement a distributed transaction is complex & creates tight coupling, which is the enemy of modern, agile architecture. So, what's the alternative? We need a different mindset. We need to manage failure, not just prevent it.
Workflow Orchestration: Your Workflow's Conductor
The first step towards sanity is often introducing an orchestrator. An orchestrator is like the conductor of an orchestra. It doesn't play any instruments itself (it doesn't contain business logic), but it tells each section when to play, what to play, & how to coordinate with the others.
In a technical sense, a workflow orchestrator is a central service that manages the execution of a multi-step process. It calls the individual services in the correct order, handles the data flow between them, &—most importantly for our discussion—manages failures.
Here’s how it helps with partial failures:
Centralized Logic: Instead of each service needing to know about the entire workflow, that logic is centralized in the orchestrator. This simplifies the individual services immensely.
State Management: The orchestrator keeps track of where the workflow is. If a step fails, it knows exactly what has been completed & what hasn't.
Error Handling: When a service fails, the orchestrator can decide what to do next. Should it retry the step? Should it trigger a fallback action? Should it cancel the whole process & undo what's been done?
This is a HUGE improvement over a "choreographed" approach where services just broadcast events & hope for the best. With an orchestrator, you have a single point of control & visibility into your complex processes.
For businesses looking to automate these kinds of complex, customer-facing workflows, this is where a tool like Arsturn becomes incredibly powerful. You can build custom AI chatbots that act as the "front door" for these processes. The chatbot can initiate the workflow, & behind the scenes, an orchestrator can manage the calls to your various internal systems (inventory, billing, CRM, etc.). If a partial failure occurs, the chatbot, guided by the resilient workflow, can provide an intelligent response to the user, like "We're just confirming inventory, this might take an extra moment!" instead of a generic error. This is how you build a seamless customer experience even when your backend systems have a momentary hiccup.
The Saga Pattern: Undoing What's Been Done
So, the orchestrator knows a step failed. Now what? Let's say in our e-commerce example, the inventory was reserved, the payment was processed, but the shipping label creation failed. We can't just leave it like that. We have an order that can't be shipped but for which we've taken money. This is where the Saga pattern comes in.
A Saga is a sequence of local transactions. Each step in the workflow is a transaction within its own service. If any of these local transactions fail, the Saga executes a series of compensating transactions to undo the work of the previous successful transactions.
Let's break that down with our order example:
Start Saga: A new order request comes in.
Transaction 1: Reserve Inventory. The Order Service tells the Inventory Service to reserve the product. The Inventory Service commits this change to its own database.
Compensating Transaction 1: Release Inventory.
Transaction 2: Process Payment. The Order Service tells the Payment Service to charge the customer's card. The Payment Service processes it.
Compensating Transaction 2: Refund Payment.
Transaction 3: Create Shipping Label. The Order Service tells the Shipping Service to create a label. Uh oh, this one fails!
Because step 3 failed, the Saga orchestrator kicks in & runs the compensating transactions in reverse order:
It triggers the "Refund Payment" transaction in the Payment Service.
It triggers the "Release Inventory" transaction in the Inventory Service.
The end result is that the system is back in a consistent state. No half-finished orders, no angry customers charged for nothing. The key is that each service is responsible for its own data & provides a way to undo its operations. This allows you to maintain data consistency across a distributed system without the nightmare of distributed transactions.
Idempotency: The "Safe to Retry" Superpower
Now, let's talk about retries. Often, a failure is transient—a temporary network blip or a service that's restarting. The simplest way to handle this is just to try again. But what happens if you retry an operation that isn't safe to retry?
Imagine the "Process Payment" step. The orchestrator calls the Payment Service, but the connection times out. The orchestrator doesn't know if the payment was actually processed before the timeout. If it just retries, it might charge the customer a second time. NOT GOOD.
This is why idempotency is one of the most critical concepts for resilient systems. An idempotent operation is one that can be performed multiple times with the same result as if it were performed only once.
How do you make an operation idempotent? A common technique is to use a unique identifier for each request.
The orchestrator generates a unique ID for the payment transaction (e.g.,
1
payment-attempt-123
).
It calls the Payment Service with this ID.
The Payment Service first checks if it has already processed a transaction with
1
payment-attempt-123
.
If yes, it doesn't process the payment again. It simply returns the result of the original transaction.
If no, it processes the payment & stores the result alongside the ID.
Now, if the orchestrator times out & retries with the same ID, the Payment Service will see it's already done it & just return the success message without double-charging the customer.
Designing your services to have idempotent APIs is a game-changer for building reliable workflows. It makes retrying operations safe & simple, which is your first line of defense against transient failures.
The Circuit Breaker Pattern: Preventing a Meltdown
Retrying is great, but what if a service is really down? If the Shipping Service is offline for maintenance, endlessly retrying the "Create Shipping Label" step is not only pointless, but it's also harmful. Your orchestrator will be wasting resources, clogging up thread pools, & potentially making the problem worse by overwhelming the struggling service the moment it tries to come back online.
This is where the Circuit Breaker pattern saves the day. Just like an electrical circuit breaker in your house, it's a safety mechanism. It monitors calls to a service, & if it detects too many failures, it "trips" or "opens" the circuit.
Here’s how it works:
Closed State: Initially, the circuit is closed, & all requests flow through to the service normally. The circuit breaker just counts the number of failures.
Open State: If the number of failures in a certain time period exceeds a configured threshold (e.g., 5 failures in 30 seconds), the circuit breaker trips & moves to the open state. Now, any further calls to that service from the orchestrator are blocked immediately without even trying to make the network call. The circuit breaker returns an error right away. This is called "failing fast."
Half-Open State: After a timeout period (e.g., 60 seconds), the circuit breaker moves to a half-open state. It will allow a single, trial request to go through to the failing service.
If that request succeeds, the circuit breaker assumes the service has recovered & moves back to the closed state, letting traffic flow again.
If that request fails, it goes back to the open state & starts the timeout timer again.
This pattern is brilliant because it protects your system from a failing dependency & gives that dependency time to recover without being hammered by constant requests. It prevents a single failing service from causing a system-wide resource exhaustion.
Tying It All Together: A Resilient Workflow in Action
Let's imagine our full, resilient e-commerce workflow now, using all these patterns:
A customer interacts with a web interface, maybe even a helpful chatbot. For businesses using Arsturn, this chatbot isn't just a simple Q&A bot. It's a sophisticated conversational AI trained on the company's own data, able to understand the customer's intent to place an order & kick off the entire backend process. It provides a seamless, personalized entry point.
The chatbot initiates the Saga via a Workflow Orchestrator.
Orchestrator to Inventory Service: The orchestrator calls the "Reserve Inventory" API, which is idempotent. A Circuit Breaker is monitoring this call. The call succeeds.
Orchestrator to Payment Service: The orchestrator then calls the "Process Payment" API, also idempotent & monitored by its own Circuit Breaker. The call succeeds.
Orchestrator to Shipping Service: The orchestrator calls the "Create Shipping Label" API. Let's say this service is temporarily down.
The first few calls fail & the retry logic kicks in.
After a few failed retries, the Circuit Breaker for the Shipping Service trips into the "Open" state.
The orchestrator now immediately gets an error when trying to call the Shipping Service. It doesn't even attempt the network call.
Failure & Compensation: The orchestrator sees this critical step has failed & the Circuit Breaker is open. It decides the order cannot be completed right now.
It initiates the compensating transactions for the Saga: it calls the "Refund Payment" API & the "Release Inventory" API.
The system is now back in a consistent state.
The User Experience: What does the customer see? Instead of a cryptic "Error 500", the orchestrator can report a specific failure state. This information can be passed back to the front end. If it was an Arsturn chatbot, it could deliver a helpful, context-aware message like, "It looks like our shipping system is a bit busy at the moment. We've saved your cart & haven't charged you. We can notify you the moment it's back up, or you can try again in a few minutes!"
That is a WORLD of difference. It transforms a frustrating failure into a managed, understandable delay.
Final Thoughts
Building systems that can gracefully recover from partial failures isn't about some magic bullet. It’s a strategic shift in design philosophy. It's about accepting that failures are a normal part of distributed systems & architecting for resilience from the ground up.
By combining powerful patterns like workflow orchestration, sagas, idempotency, & circuit breakers, you move from building fragile glass houses to robust, flexible systems that can bend without breaking. You create workflows that are not only more reliable & easier to maintain but also provide a MUCH better experience for your end-users. And in today's world, that's what separates the good from the great.
Hope this was helpful! Let me know what you think. It's a deep topic, but getting these fundamentals right can save you a world of headaches down the road.