Breaking Bottlenecks: Applying the Theory of Constraints to Software Development

Introduction

The Theory of Constraints (TOC) is a problem-solving and continuous improvement methodology first introduced by Dr. Eliyahu M. Goldratt in his book The Goal. Although TOC originally gained popularity in manufacturing and supply chain management, its application soon became far broader: at its core, TOC asserts that any system has at least one limiting factor—or “bottleneck”—that determines its overall efficiency. By identifying and eliminating this constraint, an organization can significantly boost productivity in virtually any process.

In my view, despite TOC’s roots in managing physical goods and delivery chains, its fundamental principles easily carry over into software development. Whether the “bottleneck” lies in code review, testing, or deployment, each stage of the software development lifecycle can become a constraint for the entire process. From my experience, finding and removing these constraints often marks the difference between slow releases and a fast, efficient workflow.

Why TOC Matters in Software

Software development is a sequence of interlinked activities—design, coding, testing, and deployment. Even a single “bottleneck” at any of these stages can slow down the entire workflow. TOC offers a sequential, structured approach to removing critical constraints one by one, rather than spreading efforts evenly across all problem areas.

By first focusing on the constraint that has the greatest impact on throughput, teams can rapidly increase overall development speed and product quality. Once that constraint is resolved or substantially reduced, we can move on to the next one. This forms a cycle of continuous improvement, which can be a very valuable addition to existing methodologies in modern development teams.

However, despite already providing an effective model for managing constraints, this approach also carries a hidden gem for all managers—a paradigm shift in how specific situations are assessed. We’ll take a closer look at this shift later in the article.

Overview of the Theory of Constraints

At its core, the Theory of Constraints (TOC) states that every system’s overall performance is limited by at least one critical factor—its “constraint.” Addressing this constraint often results in a large improvement in throughput or efficiency, as opposed to spreading efforts evenly across multiple areas.

The Five Focusing Steps

1. Identify the Constraint: Pinpoint the single process, resource, or condition that most limits the system's performance.
2. Exploit the Constraint: Maximize the use of the constraint to get as much output as possible, often by removing inefficiencies or prioritizing tasks.
3. Subordinate Other Processes: Align other parts of the workflow to support the constraint's needs, ensuring that they don't overload or starve it.
4. Elevate the Constraint: If throughput is still insufficient, take more significant action—such as adding resources, automation, or training—to boost the constraint's capacity.
5. Repeat the Process: Once one constraint is resolved, move on to the next limiting factor and continue the cycle of improvement.

Common Misconceptions

1. “TOC is Only for Manufacturing.” - While TOC gained fame in factory settings, its core idea of addressing the biggest bottleneck applies to any process-oriented environment—including software development.
2. “Constraints Must Be Physical.” - Constraints can be intangible, like team expertise, code review queues, or external approvals. Non-physical limitations can slow progress just as effectively as physical ones.
3. “You Only Solve One Constraint and You’re Done.” - In reality, once you elevate one constraint, another will eventually emerge as the new bottleneck. TOC is a continuous process of improvement rather than a one-off solution.

Identifying Constraints in Software Development

Common Bottlenecks

• Code Review Queues: Picture a scenario where every feature branch must be approved by a single senior engineer—this person becomes the narrowest part of the pipeline. Updates pile up, developers wait longer, and momentum stalls.
• Testing Environment: Imagine a QA team that needs hours (or days) to complete a heavy regression test suite on a limited number of environments. Even if the developers are quick, the wait for testing results stops the overall flow.
• Deployment Pipeline: If every release requires an unwieldy list of manual steps or sign-offs, deployment becomes the bottleneck. Teams might hesitate to release often, slowing the feedback loop and overall progress.
• Skill Set Constraints: Consider a complex data migration project that only one database expert can handle. When that person is swamped, development stalls, making that specialized skill set the main constraint.

Signs of a Constraint

• Prolonged Wait Times: A step in your process where tasks perpetually queue up—like PRs waiting days for review—is a giveaway that you’ve hit a bottleneck.
• Unbalanced Workload: One engineer is buried in tasks while others stay relatively idle. This imbalance often points to a specialized skill (or approval authority) causing delays.
• Frequent Context Switching: If developers keep pausing tasks because they’re waiting for a resource, environment, or final sign-off, that’s another red flag of a bottleneck.

Methods of Detection

• Process Mapping and Value Stream Analysis: Map out each stage of development (e.g., design, coding, review, testing, release) to visualize where work backs up. A simple flowchart or Kanban board can reveal exactly where tasks are piling up.
• Tracking Lead Times and Throughput: Keep tabs on how long it takes for work items—like user stories or tickets—to move from “In Progress” to “Done.” A spike in lead time at a particular stage often exposes the constraint.
• Data-Driven Observations: Use agile tools (e.g., Jira) or CI/CD metrics (e.g., build times, deployment frequency) to spot any stages that are chronically slow or stuck. This empirical evidence complements your team’s intuition, helping confirm the real culprit.

Exploiting the Constraint

Maximizing the Constraint’s Output

1. Prioritize Key Tasks: If a single engineer is the main reviewer or approver, funnel the most critical pull requests to them first. Non-urgent tasks can be scheduled later, ensuring the constraint focuses on high-impact work.
2. Automate Repetitive Steps: If QA is the bottleneck, reduce manual testing by implementing automated test suites—especially for unit and integration tests. This lightens the QA team’s load so they can focus on specialized or exploratory testing.
3. Streamline Work Handoffs: For code review, set up clear guidelines and linting tools to reduce back-and-forth on minor issues. This ensures that the constraint resource only deals with meaningful feedback rather than trivial fixes.

Resource Allocation

1. Dedicate Focus: If a key person or team is perpetually swamped, reassign or defer their lower-priority responsibilities. For instance, if the lead engineer is also doing production support, consider shifting that support role to another team member.
2. Enhance Tooling: Provide the necessary software or hardware to enable faster throughput. For example, invest in more powerful build servers, testing infrastructures, or specialized IDE plugins that reduce a bottleneck’s friction.
3. Remove Bottleneck Distractions: Give the constraint “air cover” by blocking out meetings or other distractions. If the goal is to speed up code reviews, ensure the reviewer has blocks of uninterrupted time to get through the queue efficiently.

Subordinating Other Processes

Adjusting Upstream and Downstream Work

1. Prevent Overloading the Constraint: If code review is the primary bottleneck, avoid throwing in too many new pull requests at once. For example, break larger tasks into smaller chunks or schedule them in a way that keeps the review queue manageable.
2. Synchronize Sprints or Kanban Boards: Plan work to match the throughput capacity of the constraint. If the testing phase is the bottleneck, don’t overload QA with more stories than they can realistically test during a sprint.
3. Stagger Task Starts: Rather than having everyone code simultaneously and then drop everything into review or testing at once, sequence the tasks to align with your bottleneck’s capacity. This smoother flow helps prevent “traffic jams.”

Collaborative Flow

1. Align on Deliverables: Ensure designers, developers, and testers share a common understanding of the constraints’ pace. By aligning deliverables and expectations, you can keep the constraint resource continuously engaged without overwhelming it.
2. Emphasize Smaller Increments: Small, frequent software increments are easier to review, test, and deploy. This reduces the potential for bottlenecks and shortens feedback loops, accelerating the discovery and resolution of issues.
3. Encourage Cross-Functional Teamwork: Where possible, pair around the bottleneck. For instance involve multiple developers to clarify any issues early on, reducing the constraint’s sole burden.

Elevating the Constraint

Longer-Term Solutions

1. Automation: If manual testing is a recurring bottleneck, automating as many test cases as possible can massively reduce the load. Similarly, if deployments slow you down, consider automating release processes through a CI/CD pipeline.
2. Upskilling & Cross-Training: Rather than relying on a single code reviewer or a single DevOps engineer, train multiple team members in these specialized areas. By expanding your team’s collective expertise, you ensure work doesn’t stall when key individuals are unavailable.
3. Process Improvements: Adopt practices that reduce friction at the constraint. For instance, using trunk-based development can simplify merges, while maintaining a well-defined branching strategy can minimize merge conflicts.

Business Alignment

1. Justify Investments: When securing the budget for automation tools or additional staff, show stakeholders the quantitative impact—e.g., how faster QA cycles or more frequent releases can lead to better user feedback and quicker time-to-market.
2. Communicate ROI: Present clear metrics (fewer defects, faster lead times, fewer rollback incidents) to build the case for ongoing investment in constraint elevation. Making these results visible fosters continued support from leadership.
3. Sustain the Gain: Once you’ve elevated a constraint—be it testing or deployment—create a culture that prevents the system from slipping back into old habits. Regularly review metrics and continue tweaking processes to retain your gains.

Repeating the Process (Continuous Improvement)

Identify the Next Constraint

1. Watch for Emerging Bottlenecks: After one constraint is elevated—be it QA, code review, or deployment—another weak link may become the new limiting factor. Keep an eye on metrics like lead time, throughput, and defect rates to spot this next bottleneck.
2. Maintain a Feedback Loop: Regularly check in with the team to gather anecdotal evidence about frustrations or delays. Sometimes, metrics alone won’t reveal the constraint as effectively as direct communication with those doing the work.
3. Stay Data-Driven: Use agile tools, CI/CD pipelines, and dashboards to pinpoint where tasks are piling up or cycle times are ballooning. Quantifying the problem makes it easier to prioritize which constraint to tackle next.

Sustaining a TOC Mindset

1. Embed Continuous Improvement into Culture: Encourage the team to routinely inspect and adapt. Retrospectives, for example, are a great time to discuss whether new constraints are emerging and how to address them.
2. Integrate with Agile and Lean Practices: TOC can work hand-in-hand with agile sprints or Kanban flows. Align the “five focusing steps” with your existing ceremonies, boards, and backlog refinement sessions so TOC becomes a natural part of everyday development.
3. Celebrate Wins and Share Lessons: When a bottleneck is removed or significantly reduced, highlight the achievement and explain how it happened. This motivates the team to keep pushing for improvements and propagates best practices across the organization.

Case Study: Breaking Through Compliance Bottlenecks in a Regulated SaaS Company

When I first started working with this SaaS company, they were struggling. Operating in a highly regulated industry, every release had to go through a rigorous compliance review. While their development teams embraced Agile, the compliance process remained manual, creating a stark mismatch between their speed of development and their ability to release features.

The symptoms were impossible to ignore: release candidates were ready within a week but sat in limbo for two more, waiting for compliance sign-offs. Their staging environment looked like a parking lot of delayed features, and rollback requests due to late-discovered compliance issues only made things worse. Developers were frustrated, compliance officers were overwhelmed, and leadership was under pressure to deliver faster.

Identifying the Constraint

When I joined, my first step was to uncover the real source of the delays. By diving into sprint metrics and sitting with both developers and compliance officers, the bottleneck became crystal clear: compliance. Work was piling up at this stage, and it wasn’t due to a single person or tool. The entire compliance team was overwhelmed by constant changes, endless documentation reviews, and a lack of automation.

The developers were fast, but the compliance officers were working with fragmented information pulled from multiple systems, manually cross-checking test logs, security scans, and architectural diagrams. It was an uphill battle.

Exploiting the Constraint

The goal wasn’t to overhaul everything overnight—it was to work smarter with the resources we already had.

Centralizing Compliance Artifacts

We built a simple, centralized dashboard. Developers now upload all compliance-related documentation—test results, security scans, architectural diagrams—into one place. This cut down the compliance team’s time wasted searching across systems.

Prioritizing High-Risk Reviews

Instead of treating every feature equally, we triaged. Features handling sensitive personal data went to the front of the line, while lower-risk updates (like UI tweaks) were batched together for quicker reviews.

Reducing Rework

We added pre-check scripts into the CI pipeline. Basic compliance checks, linting, and static analysis caught minor errors before they reached the compliance stage. By the time features arrived for review, they were cleaner and required less back-and-forth.

Subordinating Other Processes

To truly exploit the constraint, the entire workflow had to adjust.

Aligning Delivery Schedules

Product managers started scheduling fewer compliance-heavy features per sprint. This avoided flooding the compliance queue and helped the team maintain steady progress.

Adopting a Shift-Left Approach

Developers, QA engineers, and even product managers were trained on compliance basics. They began documenting critical data flows upfront, ensuring fewer surprises at the final review stage.

Breaking Down Big Deliveries

Instead of shipping massive releases, we transitioned to smaller, incremental deliveries. This smoothed out the workload for compliance and reduced the “end-of-sprint crunch” that had plagued the team.

Elevating the Constraint

With the compliance process stabilized, it was time to think long-term.

Investing in Automation

We implemented a compliance tool to handle repetitive checks against industry regulations. This drastically reduced the manual burden on compliance officers.

Cross-Training Compliance Champions

We identified key developers and QA leads who could handle pre-compliance reviews. By spreading this knowledge, the team became less dependent on a small group of experts.

Bringing in External Help

For specialized areas like legal or privacy compliance, we brought in additional personnel. The ROI was clear: fewer delays meant features reached customers faster, and regulatory risks were mitigated.

Repeating the Process

Once compliance was no longer the bottleneck, a new constraint emerged: performance testing. As releases sped up, the load-testing pipeline couldn’t keep pace, leading to sporadic late-stage failures.

We applied the same TOC principles: identified the bottleneck, streamlined the process, and elevated it through automation and better resource allocation.

Outcome

Focusing on the compliance bottleneck transformed the company’s delivery process. Release velocity improved significantly, all while maintaining the strict regulatory standards required by their industry. The TOC mindset didn’t just fix one problem—it created a ripple effect. With every bottleneck resolved, the next weakest link came into focus, driving ongoing improvements across the board.

Conclusion

TOC is about focus. Instead of spreading efforts thinly across all problems, it zeroes in on the single biggest bottleneck. This principle, when applied in software development, can dramatically boost efficiency and streamline delivery.

Constraints aren’t always physical. They might come in the form of code reviews, compliance checks, or specialized expertise. These intangible bottlenecks can derail progress just as much as any technical limitation, yet they are often overlooked.

TOC drives continuous improvement. Fixing one constraint will often reveal the next. This repeatable process keeps teams moving forward, consistently enhancing their workflows and outcomes.

Alignment is critical. To elevate constraints effectively, securing buy-in from stakeholders is essential. By presenting clear metrics and demonstrating ROI, you can build the momentum and support needed for automation, tooling, or staffing changes.

Perhaps most importantly, TOC brings a shift in the manager’s mindset. Instead of framing goals in terms of “To achieve X, I need to do W, Y, and Z,” this approach encourages you to ask, “What is the single biggest constraint preventing me from reaching X?” This change in perspective transforms how priorities are set and challenges are tackled, leading to sharper decision-making and more impactful results.

Call to Action

As a manager, you’ve likely faced constraints that feel elusive or overwhelming. TOC provides a practical way to identify, understand, and address these bottlenecks systematically. Here’s how you can take immediate, actionable steps:

1. Map Your Workflow: Start by gaining visibility into your processes. Break down the software development lifecycle into key stages—design, coding, code review, testing, and deployment—and map how tasks flow through each step. Use tools like Kanban boards, value stream mapping, or even simple flowcharts to visualize where work accumulates or stalls.
2. Focus on Small, Actionable Changes: Constraints can feel overwhelming, but the solution often starts with small, focused improvements. For instance: smaller PRs, more QA automation, streamline releases and deployments.
3. Iterate Relentlessly: Recognize that solving one constraint doesn’t mean your work is done. Addressing a bottleneck will likely reveal a new one. Embrace this iterative process. Monitor lead times, backlog growth, and defect rates regularly. These metrics will guide you to the next most pressing issue.
4. Engage and Empower Your Team: Remember, you’re not tackling constraints alone. Collaborate with your team to both: identify bottlenecks and experiment with solutions. Empower individuals to propose changes and take ownership of specific improvements.
5.  Mindset Shift: Rather than managing every detail, guide your team by asking, “What is the biggest obstacle stopping us from succeeding here?” This fosters a culture of proactive problem-solving.
6. Adopt a Long-Term Mindset: TOC is not about quick fixes—it’s about cultivating a mindset of continuous improvement. Commit to revisiting your processes regularly, and don’t shy away from investments in automation, training, or tooling where it aligns with the long-term health of your workflow.

Final Thoughts

Facing constraints as a manager can be frustrating, but with TOC, the path forward becomes clearer: identify the biggest barrier, focus on resolving it, and use that momentum to tackle the next challenge. TOC isn’t a one-time solution; it’s a mindset for continuous improvement. Success isn’t just about removing one bottleneck—it’s about embracing a process that keeps you and your team moving forward. When combined with Agile, Lean, or DevOps practices, it can accelerate delivery, maintain high-quality standards, and foster a culture of progress.